# Fprintf support in CATS files effects compilation for embedded target

**URL:** <https://discourse.ats-lang.org/t/fprintf-support-in-cats-files-effects-compilation-for-embedded-target/257>\
**Category:** Google Group\
**Created:** [September 19, 2015, 7:52pm UTC](https://discourse.ats-lang.org/t/fprintf-support-in-cats-files-effects-compilation-for-embedded-target/257 "2015-09-19T19:52:56Z")\
**Posts on this page:** 20\
**Page:** 1

<div class="post-metadata">

**Author:** ![Mike\_Jones](https://avatars.discourse-cdn.com/v4/letter/m/74df32/32.png) [@Mike\_Jones](https://discourse.ats-lang.org/u/Mike_Jones)\
**Post date:** [September 19, 2015, 7:52pm UTC](https://discourse.ats-lang.org/t/fprintf-support-in-cats-files-effects-compilation-for-embedded-target/257/1 "2015-09-19T19:52:56Z")

</div>

I’m adding some I2C support to arduino-ats and decided to look under the  
hood to see why the arduino prelude uses modified versions of CATS files,  
and see if it would be possible to use the standard prelude for ATS2. It  
looks like the primary reason for copying CATS files, is to remove code  
related to stdio and printing.

This leads to some questions about how enable the embedded developers at  
the end of the discussion of things I tried to get around the problem.

Some discussion of things I tried…

As an experiment, I forced the inclusion of the avr version of stdio.h and  
it creates errors because stderr/out/in are macros, and the avr toolchain  
seems to have a problem with nested macros. As an experiment, I changed the  
stdio.h to have these definitions:

extern struct \_\_file _stdin; /_ Standard input stream. \*/  
extern struct \_\_file _stdout; /_ Standard output stream. \*/  
extern struct \_\_file _stderr; /_ Standard error output stream. \*/

Which removes the error and leaves the following error:

/opt/ATS/ATS2-Postiats-0.2.2/prelude/CATS/integer.cats:980:55: error:  
expected ‘)’ before ‘(’ token  
#define atspre\_print\_int(x) atspre\_fprint\_int(stdout, (x))

```
  ^

```

In case of spacing in the text, the ^ is at (x)

The code called from this generated code in the .c file:

ATSextern()  
atsvoid\_t0ype  
atspre\_print\_int(atstkind\_t0ype(atstype\_int) arg0)  
{  
/\* tmpvardeclst(beg) \*/  
// ATStmpdec\_void(tmpret80) ;  
ATStmpdec(tmpref81[32], atstkind\_t0ype(atstype\_byte)) ;

I assume the compiler is bumping into a similar nested macro problem.

Back to the real question.

Stdio is not something always available when you are dealing with bare iron  
or RTOS based platforms, and often it is senseless. So I am asking how  
might this be addressed? My thoughts are that faking out ATS with functions  
that are not needed is a poor approach. I think it would make more sense to  
have a #define to either turn off everything related to stdio, or allow for  
user definitions, or both. Another approach might be to factor out the code  
into one file/interface so that an application can simply not include it.

In general, I think coupling any core libraries to IO or an OS API will  
limit the user base, if those libraries are essential to quick success.

Thoughts?

Mike

---

<div class="post-metadata">

**Author:** ![gmhwxi](https://avatars.discourse-cdn.com/v4/letter/g/67e7ee/32.png) [@gmhwxi](https://discourse.ats-lang.org/u/gmhwxi)\
**Post date:** [September 19, 2015, 10:17pm UTC](https://discourse.ats-lang.org/t/fprintf-support-in-cats-files-effects-compilation-for-embedded-target/257/2 "2015-09-19T22:17:33Z")

</div>

There should really be no problems with using avr/stdio.h.

I think the reason for your trouble is that functions like print\_int and  
print\_string  
are not defined based on avr/stdio.h.

> > extern struct \_\_file _stdin; /_ Standard input stream. \*/  
> > extern struct \_\_file _stdout; /_ Standard output stream. \*/  
> > extern struct \_\_file _stderr; /_ Standard error output stream. \*/

This is problematic. Do not make use of ‘stdin’ if it is not available. If  
you post some  
code, I will prbably suggest something more concrete.On Sat, Sep 19, 2015 at 3:52 PM, Mike Jones [proc...@gmail.com](mailto:proc...@gmail.com) wrote:

> I’m adding some I2C support to arduino-ats and decided to look under the  
> hood to see why the arduino prelude uses modified versions of CATS files,  
> and see if it would be possible to use the standard prelude for ATS2. It  
> looks like the primary reason for copying CATS files, is to remove code  
> related to stdio and printing.
> 
> This leads to some questions about how enable the embedded developers at  
> the end of the discussion of things I tried to get around the problem.
> 
> Some discussion of things I tried…
> 
> As an experiment, I forced the inclusion of the avr version of stdio.h and  
> it creates errors because stderr/out/in are macros, and the avr toolchain  
> seems to have a problem with nested macros. As an experiment, I changed the  
> stdio.h to have these definitions:
> 
> extern struct \_\_file _stdin; /_ Standard input stream. \*/  
> extern struct \_\_file _stdout; /_ Standard output stream. \*/  
> extern struct \_\_file _stderr; /_ Standard error output stream. \*/
> 
> Which removes the error and leaves the following error:
> 
> /opt/ATS/ATS2-Postiats-0.2.2/prelude/CATS/integer.cats:980:55: error:  
> expected ‘)’ before ‘(’ token  
> #define atspre\_print\_int(x) atspre\_fprint\_int(stdout, (x))
> 
> ```
> ^
> 
> ```
> 
> In case of spacing in the text, the ^ is at (x)
> 
> The code called from this generated code in the .c file:
> 
> ATSextern()  
> atsvoid\_t0ype  
> atspre\_print\_int(atstkind\_t0ype(atstype\_int) arg0)  
> {  
> /\* tmpvardeclst(beg) \*/  
> // ATStmpdec\_void(tmpret80) ;  
> ATStmpdec(tmpref81[32], atstkind\_t0ype(atstype\_byte)) ;
> 
> I assume the compiler is bumping into a similar nested macro problem.
> 
> Back to the real question.
> 
> Stdio is not something always available when you are dealing with bare  
> iron or RTOS based platforms, and often it is senseless. So I am asking how  
> might this be addressed? My thoughts are that faking out ATS with functions  
> that are not needed is a poor approach. I think it would make more sense to  
> have a #define to either turn off everything related to stdio, or allow for  
> user definitions, or both. Another approach might be to factor out the code  
> into one file/interface so that an application can simply not include it.
> 
> In general, I think coupling any core libraries to IO or an OS API will  
> limit the user base, if those libraries are essential to quick success.
> 
> Thoughts?
> 
> Mike
> 
> –  
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> .

---

<div class="post-metadata">

**Author:** ![Mike\_Jones](https://avatars.discourse-cdn.com/v4/letter/m/74df32/32.png) [@Mike\_Jones](https://discourse.ats-lang.org/u/Mike_Jones)\
**Post date:** [September 29, 2015, 12:15am UTC](https://discourse.ats-lang.org/t/fprintf-support-in-cats-files-effects-compilation-for-embedded-target/257/3 "2015-09-29T00:15:37Z")

</div>

You can remove the reference. The file is still an empty placeholder.\> On Sep 28, 2015, at 7:28 AM, Kiwamu Okabe [kiw...@debian.or.jp](mailto:kiw...@debian.or.jp) wrote:

> Hi Mike,
> 
> > On Sat, Sep 26, 2015 at 11:46 PM, Mike Jones [proc...@gmail.com](mailto:proc...@gmail.com) wrote:  
> > Attached is a patch that has twi, smbus, and changes the prelude, plus  
> > removal of cats files.
> > 
> > You already updated the makefile for the new release.
> > 
> > I tested 01\_blink. Others compile, but I did not test them.
> > 
> > The i2c/smbus demos are specific to my PMBus hardware. If there is some  
> > standard shield everyone uses a lot, they could be modified for a more  
> > common hardware.
> 
> Thank’s. I merged your patch.
> 
> [Import Mike's ats23.patch · fpiot/arduino-ats@a0d7941 · GitHub](https://github.com/fpiot/arduino-ats/commit/a0d79410292156d34bde76c5063389f813ae5a2c)
> 
> However my build has following error:
> 
> $ pwd  
> /home/kiwamu/src/arduino-ats/demo/i2c  
> $ make  
> patsopt -o DATS/main\_dats.c.tmp -d DATS/main.dats  
> /home/kiwamu/src/arduino-ats/demo/i2c/DATS/main.dats: 217(line=8,  
> offs=1) – 249(line=8, offs=33): error(1): the file  
> [{$TOP}/SATS/pmbus.sats] is not available for staloading.
> 
> Do you have the pmbus.sats file?
> 
> ## Thank’s a lot,
> 
> Kiwamu Okabe at METASEPI DESIGN
> 
> –  
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---

<div class="post-metadata">

**Author:** ![gmhwxi](https://avatars.discourse-cdn.com/v4/letter/g/67e7ee/32.png) [@gmhwxi](https://discourse.ats-lang.org/u/gmhwxi)\
**Post date:** [September 20, 2015, 4:39pm UTC](https://discourse.ats-lang.org/t/fprintf-support-in-cats-files-effects-compilation-for-embedded-target/257/4 "2015-09-20T16:39:04Z")

</div>

To be honest, I am not yet clear as to what problem needs to be solved here.

I see that you have the following line in your code:

> > #include “prelude/CATS/integer.cats”

Is it that you want to modify prelude/CATS/integer.cats so that it could  
work  
with avr-cc?On Sunday, September 20, 2015 at 11:10:20 AM UTC-4, Mike Jones wrote:

> Let me get a bit more specific about the error and see if you can help  
> make it work with the avr stdio.h
> 
> I changed the avr\_prelude like this, so that stdio.h is included before  
> the ats prelude.
> 
> #include “stdio.h”  
> #include “prelude/CATS/integer.cats”  
> #include “avr\_prelude/CATS/pointer.cats”  
> …
> 
> Basically, just try one file from the ats prelude. In the errors below, I  
> have used bold type where the caret points to the error.
> 
> The default avr stdio.h has:
> 
> The default stdio.h has:
> 
> struct \_\_file {  
> char _buf; /_ buffer pointer _/  
> unsigned char unget; /_ ungetc() buffer \*/  
> uint8\_t flags;  
> …
> 
> extern struct \_\_file \*\_\_iob;  
> #define stdin (\_\_iob[0])  
> #define stdout (\_\_iob[1])  
> #define stderr (\_\_iob[2])
> 
> Here is an example error from the compile:
> 
> In file included from …/…/avr\_prelude/kernel\_prelude.cats:7:0,  
> from hardware\_serial\_dats.c:57:  
> hardware\_serial\_dats.c: At top level:  
> /opt/ATS/ATS2-Postiats-0.2.2/prelude/CATS/integer.cats:980:47: error:  
> expected declaration specifiers or ‘…’ before ‘(’ token  
> #define atspre\_print\_int(x) atspre\_fprint\_int(_stdout_, (x))
> 
> hardware\_serial\_dats.c:2264:1: note: in expansion of macro  
> ‘atspre\_print\_int’  
> atspre\_print\_int(atstkind\_t0ype(atstype\_int) arg0)  
> ^
> 
> Now I change the definition to the following to remove the stdxx macros:
> 
> > > > extern struct \_\_file _stdin; /_ Standard input stream. \*/  
> > > > extern struct \_\_file _stdout; /_ Standard output stream. \*/  
> > > > extern struct \_\_file _stderr; /_ Standard error output stream.  
> > > > \*/
> 
> The error becomes:
> 
> In file included from  
> /home/mike/arduino-ats/avr\_prelude/kernel\_prelude.cats:8:0,  
> from hardware\_serial\_dats.c:57:  
> hardware\_serial\_dats.c: At top level:  
> /opt/ATS/ATS2-Postiats-0.2.2/prelude/CATS/integer.cats:980:55: error:  
> expected ‘)’ before ‘(’ token  
> #define atspre\_print\_int(x) atspre\_fprint\_int(stdout, _(x)_)
> 
> hardware\_serial\_dats.c:2264:1: note: in expansion of macro  
> ‘atspre\_print\_int’  
> atspre\_print\_int(atstkind\_t0ype(atstype\_int) arg0)  
> ^
> 
> My interpretation is the preprocessor can’t expand the nested macro, in  
> both cases.
> 
> I was mainly surprised at the error when using the modified stdio.h

---

<div class="post-metadata">

**Author:** ![gmhwxi](https://avatars.discourse-cdn.com/v4/letter/g/67e7ee/32.png) [@gmhwxi](https://discourse.ats-lang.org/u/gmhwxi)\
**Post date:** [September 23, 2015, 1:36am UTC](https://discourse.ats-lang.org/t/fprintf-support-in-cats-files-effects-compilation-for-embedded-target/257/5 "2015-09-23T01:36:05Z")

</div>

You can find a pre-stable release of ATS2-0.2.3 at:

[http://www.ats-lang.org/Downloads.html](http://www.ats-lang.org/Downloads.html)

It is a tarball I made earlier tonight. Let me know if it works.

> <https://github.com/githwxi/ATS-Postiats-contrib/tree/master/contrib/arduino>
>
> //github.com/githwxi/ATS-Postiats-contrib/tree/master/contrib/arduino

> <https://github.com/githwxi/ATS-Postiats-contrib/blob/master/contrib/arduino/H/pats_ccomp.h>

I briefly tested the new pats\_ccomp.h. It seems to be working.On Tuesday, September 22, 2015 at 9:21:20 PM UTC-4, Mike Jones wrote:

> Dumping the CATS files into arduino-ats gets into trouble with missing  
> files like ats\_types.h. So perhaps its better to build it, but the git repo  
> does not have the proper configure and makefiles. I tried the ones from the  
> tarball, which is not quite recent enough to have the refactored CATS  
> files, but I get failures straight away.
> 
> If there are some files/instructions for compilation of the upcoming  
> release, I would be happy to test with arduino-ats, or if there you can  
> update the tarball, that would be even better.
> 
> I have a fully working app now, so I can make sure I can compile  
> arduino-ats without any modified files and then make sure the app is  
> working. That would be real nice before the actual release.

---

<div class="post-metadata">

**Author:** ![Mike\_Jones](https://avatars.discourse-cdn.com/v4/letter/m/74df32/32.png) [@Mike\_Jones](https://discourse.ats-lang.org/u/Mike_Jones)\
**Post date:** [September 21, 2015, 5:07am UTC](https://discourse.ats-lang.org/t/fprintf-support-in-cats-files-effects-compilation-for-embedded-target/257/6 "2015-09-21T05:07:32Z")

</div>

My concern is that different CATS files for the embedded world means 20+ of  
them to cover RTOS, SDKs, ARM/i386, etc.

A generator would be nice I suppose, but that can get complicated. I think  
that just moves the complexity, but does not solve it. What happens when  
the script generator creates code that does not compile and everyone blames  
ATS?

I think it would be fine to have something like how memory is handled. You  
can have MALLOC, GC, or user.

It would be a fair question to ask what about other couplings. From what I  
have seen so far, there is not much coupling except stdio. Everything else  
seems to be pure C.On Sunday, September 20, 2015 at 4:24:17 PM UTC-6, gmhwxi wrote:

> To me, using a different set of CATS files for arduino-ats is a reasonable  
> design for otherwise we may have to introduce a lot of #if-guards, which  
> could  
> be confusing (and likely harder to maintain).
> 
> Actually, it will be really good if someone can write a script for  
> automatically generating  
> CATS files targeting different platforms.
> 
> On Sunday, September 20, 2015 at 5:17:26 PM UTC-4, Mike Jones wrote:
> 
> > There are two parts:
> > 
> > A) Undertand the compilation error and see if there is a work around,  
> > with the goal of removing the copied/modifed versions of CATS files in  
> > arduino-ats, because it will be hard to maintain a copy
> > 
> > B) See if there is reason for prelude/CATS/integer.cats and other cats  
> > files to be modified in some way to remove stdio for those targets that  
> > can’t support it. By remove, I don’t mean copy/modify, but to modify the  
> > files for an ATS release.
> > 
> > I am basically saying that coupling the CATS files to IO too tightly  
> > makes ATS difficult for embedded users and I am searching for a solution,  
> > because for me ATS’s highest value is for embedded platforms.
> > 
> > On Sunday, September 20, 2015 at 10:39:04 AM UTC-6, gmhwxi wrote:
> > 
> > > To be honest, I am not yet clear as to what problem needs to be solved  
> > > here.
> > > 
> > > I see that you have the following line in your code:
> > > 
> > > > > #include “prelude/CATS/integer.cats”
> > > 
> > > Is it that you want to modify prelude/CATS/integer.cats so that it could  
> > > work  
> > > with avr-cc?
> > > 
> > > On Sunday, September 20, 2015 at 11:10:20 AM UTC-4, Mike Jones wrote:
> > > 
> > > > Let me get a bit more specific about the error and see if you can help  
> > > > make it work with the avr stdio.h
> > > > 
> > > > I changed the avr\_prelude like this, so that stdio.h is included before  
> > > > the ats prelude.
> > > > 
> > > > #include “stdio.h”  
> > > > #include “prelude/CATS/integer.cats”  
> > > > #include “avr\_prelude/CATS/pointer.cats”  
> > > > …
> > > > 
> > > > Basically, just try one file from the ats prelude. In the errors below,  
> > > > I have used bold type where the caret points to the error.
> > > > 
> > > > The default avr stdio.h has:
> > > > 
> > > > The default stdio.h has:
> > > > 
> > > > struct \_\_file {  
> > > > char _buf; /_ buffer pointer _/  
> > > > unsigned char unget; /_ ungetc() buffer \*/  
> > > > uint8\_t flags;  
> > > > …
> > > > 
> > > > extern struct \_\_file \*\_\_iob;  
> > > > #define stdin (\_\_iob[0])  
> > > > #define stdout (\_\_iob[1])  
> > > > #define stderr (\_\_iob[2])
> > > > 
> > > > Here is an example error from the compile:
> > > > 
> > > > In file included from …/…/avr\_prelude/kernel\_prelude.cats:7:0,  
> > > > from hardware\_serial\_dats.c:57:  
> > > > hardware\_serial\_dats.c: At top level:  
> > > > /opt/ATS/ATS2-Postiats-0.2.2/prelude/CATS/integer.cats:980:47: error:  
> > > > expected declaration specifiers or ‘…’ before ‘(’ token  
> > > > #define atspre\_print\_int(x) atspre\_fprint\_int(_stdout_, (x))
> > > > 
> > > > hardware\_serial\_dats.c:2264:1: note: in expansion of macro  
> > > > ‘atspre\_print\_int’  
> > > > atspre\_print\_int(atstkind\_t0ype(atstype\_int) arg0)  
> > > > ^
> > > > 
> > > > Now I change the definition to the following to remove the stdxx macros:
> > > > 
> > > > > > > extern struct \_\_file _stdin; /_ Standard input stream. \*/  
> > > > > > > extern struct \_\_file _stdout; /_ Standard output stream. \*/  
> > > > > > > extern struct \_\_file _stderr; /_ Standard error output  
> > > > > > > stream. \*/
> > > > 
> > > > The error becomes:
> > > > 
> > > > In file included from  
> > > > /home/mike/arduino-ats/avr\_prelude/kernel\_prelude.cats:8:0,  
> > > > from hardware\_serial\_dats.c:57:  
> > > > hardware\_serial\_dats.c: At top level:  
> > > > /opt/ATS/ATS2-Postiats-0.2.2/prelude/CATS/integer.cats:980:55: error:  
> > > > expected ‘)’ before ‘(’ token  
> > > > #define atspre\_print\_int(x) atspre\_fprint\_int(stdout, _(x)_)
> > > > 
> > > > hardware\_serial\_dats.c:2264:1: note: in expansion of macro  
> > > > ‘atspre\_print\_int’  
> > > > atspre\_print\_int(atstkind\_t0ype(atstype\_int) arg0)  
> > > > ^
> > > > 
> > > > My interpretation is the preprocessor can’t expand the nested macro, in  
> > > > both cases.
> > > > 
> > > > I was mainly surprised at the error when using the modified stdio.h

---

<div class="post-metadata">

**Author:** ![Mike\_Jones](https://avatars.discourse-cdn.com/v4/letter/m/74df32/32.png) [@Mike\_Jones](https://discourse.ats-lang.org/u/Mike_Jones)\
**Post date:** [September 20, 2015, 9:17pm UTC](https://discourse.ats-lang.org/t/fprintf-support-in-cats-files-effects-compilation-for-embedded-target/257/7 "2015-09-20T21:17:26Z")

</div>

There are two parts:

A) Undertand the compilation error and see if there is a work around, with  
the goal of removing the copied/modifed versions of CATS files in  
arduino-ats, because it will be hard to maintain a copy

B) See if there is reason for prelude/CATS/integer.cats and other cats  
files to be modified in some way to remove stdio for those targets that  
can’t support it. By remove, I don’t mean copy/modify, but to modify the  
files for an ATS release.

I am basically saying that coupling the CATS files to IO too tightly makes  
ATS difficult for embedded users and I am searching for a solution, because  
for me ATS’s highest value is for embedded platforms.On Sunday, September 20, 2015 at 10:39:04 AM UTC-6, gmhwxi wrote:

> To be honest, I am not yet clear as to what problem needs to be solved  
> here.
> 
> I see that you have the following line in your code:
> 
> > > #include “prelude/CATS/integer.cats”
> 
> Is it that you want to modify prelude/CATS/integer.cats so that it could  
> work  
> with avr-cc?
> 
> On Sunday, September 20, 2015 at 11:10:20 AM UTC-4, Mike Jones wrote:
> 
> > Let me get a bit more specific about the error and see if you can help  
> > make it work with the avr stdio.h
> > 
> > I changed the avr\_prelude like this, so that stdio.h is included before  
> > the ats prelude.
> > 
> > #include “stdio.h”  
> > #include “prelude/CATS/integer.cats”  
> > #include “avr\_prelude/CATS/pointer.cats”  
> > …
> > 
> > Basically, just try one file from the ats prelude. In the errors below, I  
> > have used bold type where the caret points to the error.
> > 
> > The default avr stdio.h has:
> > 
> > The default stdio.h has:
> > 
> > struct \_\_file {  
> > char _buf; /_ buffer pointer _/  
> > unsigned char unget; /_ ungetc() buffer \*/  
> > uint8\_t flags;  
> > …
> > 
> > extern struct \_\_file \*\_\_iob;  
> > #define stdin (\_\_iob[0])  
> > #define stdout (\_\_iob[1])  
> > #define stderr (\_\_iob[2])
> > 
> > Here is an example error from the compile:
> > 
> > In file included from …/…/avr\_prelude/kernel\_prelude.cats:7:0,  
> > from hardware\_serial\_dats.c:57:  
> > hardware\_serial\_dats.c: At top level:  
> > /opt/ATS/ATS2-Postiats-0.2.2/prelude/CATS/integer.cats:980:47: error:  
> > expected declaration specifiers or ‘…’ before ‘(’ token  
> > #define atspre\_print\_int(x) atspre\_fprint\_int(_stdout_, (x))
> > 
> > hardware\_serial\_dats.c:2264:1: note: in expansion of macro  
> > ‘atspre\_print\_int’  
> > atspre\_print\_int(atstkind\_t0ype(atstype\_int) arg0)  
> > ^
> > 
> > Now I change the definition to the following to remove the stdxx macros:
> > 
> > > > > extern struct \_\_file _stdin; /_ Standard input stream. \*/  
> > > > > extern struct \_\_file _stdout; /_ Standard output stream. \*/  
> > > > > extern struct \_\_file _stderr; /_ Standard error output stream.  
> > > > > \*/
> > 
> > The error becomes:
> > 
> > In file included from  
> > /home/mike/arduino-ats/avr\_prelude/kernel\_prelude.cats:8:0,  
> > from hardware\_serial\_dats.c:57:  
> > hardware\_serial\_dats.c: At top level:  
> > /opt/ATS/ATS2-Postiats-0.2.2/prelude/CATS/integer.cats:980:55: error:  
> > expected ‘)’ before ‘(’ token  
> > #define atspre\_print\_int(x) atspre\_fprint\_int(stdout, _(x)_)
> > 
> > hardware\_serial\_dats.c:2264:1: note: in expansion of macro  
> > ‘atspre\_print\_int’  
> > atspre\_print\_int(atstkind\_t0ype(atstype\_int) arg0)  
> > ^
> > 
> > My interpretation is the preprocessor can’t expand the nested macro, in  
> > both cases.
> > 
> > I was mainly surprised at the error when using the modified stdio.h

---

<div class="post-metadata">

**Author:** ![Mike\_Jones](https://avatars.discourse-cdn.com/v4/letter/m/74df32/32.png) [@Mike\_Jones](https://discourse.ats-lang.org/u/Mike_Jones)\
**Post date:** [September 29, 2015, 12:16am UTC](https://discourse.ats-lang.org/t/fprintf-support-in-cats-files-effects-compilation-for-embedded-target/257/8 "2015-09-29T00:16:51Z")

</div>

I am interested, but was looking a ecos, which is mature, full featured, and I am familiar.\> On Sep 28, 2015, at 7:35 AM, Kiwamu Okabe [kiw...@debian.or.jp](mailto:kiw...@debian.or.jp) wrote:

> Hi Mike,
> 
> > On Sun, Sep 27, 2015 at 1:08 AM, Mike Jones [proc...@gmail.com](mailto:proc...@gmail.com) wrote:  
> > Longer term, I am interested in getting arduino-ats working on Arduino Zero  
> > as I need that level of performance. However, the library code for Zero  
> > needs to mature, mainly that the i2c layer does not yet do a repeated start.
> 
> Are you interested in an application on some RTOS? I have some plan for it.
> 
> [GitHub - fpiot/mbed-ats: ATS programing on mbed platform](https://github.com/fpiot/mbed-ats)  
> [GitHub - fpiot/chibios-ats: ATS programing on ChibiOS/RT](https://github.com/fpiot/chibios-ats)
> 
> I think these applications are easy to use linear types with dataviewtype,  
> because they can use malloc of RTOS.
> 
> And so, I think you are better person than me to build ATS application on small  
> embedded system. Could you join Functional IoT project [Functional IoT · GitHub](https://github.com/fpiot)  
> with your github account?
> 
> ## Thank’s,
> 
> Kiwamu Okabe at METASEPI DESIGN
> 
> –  
> You received this message because you are subscribed to a topic in the Google Groups “ats-lang-users” group.  
> To unsubscribe from this topic, visit [https://groups.google.com/d/topic/ats-lang-users/\_N1xLDQ-Lgk/unsubscribe](https://groups.google.com/d/topic/ats-lang-users/_N1xLDQ-Lgk/unsubscribe).  
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---

<div class="post-metadata">

**Author:** ![Mike\_Jones](https://avatars.discourse-cdn.com/v4/letter/m/74df32/32.png) [@Mike\_Jones](https://discourse.ats-lang.org/u/Mike_Jones)\
**Post date:** [September 23, 2015, 1:21am UTC](https://discourse.ats-lang.org/t/fprintf-support-in-cats-files-effects-compilation-for-embedded-target/257/9 "2015-09-23T01:21:20Z")

</div>

Dumping the CATS files into arduino-ats gets into trouble with missing  
files like ats\_types.h. So perhaps its better to build it, but the git repo  
does not have the proper configure and makefiles. I tried the ones from the  
tarball, which is not quite recent enough to have the refactored CATS  
files, but I get failures straight away.

If there are some files/instructions for compilation of the upcoming  
release, I would be happy to test with arduino-ats, or if there you can  
update the tarball, that would be even better.

I have a fully working app now, so I can make sure I can compile  
arduino-ats without any modified files and then make sure the app is  
working. That would be real nice before the actual release.

---

<div class="post-metadata">

**Author:** ![Mike\_Jones](https://avatars.discourse-cdn.com/v4/letter/m/74df32/32.png) [@Mike\_Jones](https://discourse.ats-lang.org/u/Mike_Jones)\
**Post date:** [September 30, 2015, 8:16pm UTC](https://discourse.ats-lang.org/t/fprintf-support-in-cats-files-effects-compilation-for-embedded-target/257/10 "2015-09-30T20:16:20Z")

</div>

Kiwamu,

That is what I expected. PMBus eventually, but not yet.

MikeOn Monday, September 28, 2015 at 8:17:13 PM UTC-6, Kiwamu Okabe wrote:

> Hi Mike,
> 
> On Tue, Sep 29, 2015 at 9:15 AM, Mike jones \<[pro...@gmail.com](mailto:pro...@gmail.com) \<javascript:\>\> wrote:
> 
> > You can remove the reference. The file is still an empty placeholder.
> 
> I can build your code with following patch:
> 
> [Remove pmbus.sats · fpiot/arduino-ats@49b9bbc · GitHub](https://github.com/fpiot/arduino-ats/commit/49b9bbce8ca07165f54e68bf7e45ae77b646a733)
> 
> ## Thank’s,
> 
> Kiwamu Okabe at METASEPI DESIGN

---

<div class="post-metadata">

**Author:** ![Mike\_Jones](https://avatars.discourse-cdn.com/v4/letter/m/74df32/32.png) [@Mike\_Jones](https://discourse.ats-lang.org/u/Mike_Jones)\
**Post date:** [September 26, 2015, 4:08pm UTC](https://discourse.ats-lang.org/t/fprintf-support-in-cats-files-effects-compilation-for-embedded-target/257/11 "2015-09-26T16:08:01Z")

</div>

My problem was resolved. Given that the application interacts via a client  
coded in Haskell over the USB, performance is not just the ATS app on the  
Arduino…

Anyway, thanks for partitioning the code. This helps clean up things for  
embedded work, and I consider my project quite successful.

I was able to grab some preexisting C code, then port the main C  
application to ATS, with no performance lost. It is very key that I can  
write code with no malloc or GC in a functional style and avoid references  
and arrays where possible. I can run Haskell on Linux on an Edison, but  
once I drop to Cortex M0 or less, ATS is the proper language.

Longer term, I am interested in getting arduino-ats working on Arduino Zero  
as I need that level of performance. However, the library code for Zero  
needs to mature, mainly that the i2c layer does not yet do a repeated start.

I don’t know what the general interest is in embedded programming with  
functional code, but I view ATS as solving some nasty problems in embedded  
work.

CheersOn Wednesday, September 23, 2015 at 9:23:20 AM UTC-6, gmhwxi wrote:

> As a rule of thumb, the C code generated by Patsopt in general needs to be  
> compiled with -O2 to  
> ensure that inlining is properly done.
> 
> On Wed, Sep 23, 2015 at 11:15 AM, Mike Jones \<[pro...@gmail.com](mailto:pro...@gmail.com) \<javascript:\>\> wrote:
> 
> > My app runs, but it is suddenly very slow. I need to debug to see if it  
> > is related to hardware, application code, or other.
> > 
> > On Tuesday, September 22, 2015 at 9:14:28 PM UTC-6, Mike Jones wrote:
> > 
> > > I was able to change the arduino-ats prelude to all point to the ATS2  
> > > distribution. Then remove all the files. Everything compiles including my  
> > > application. 01\_blink works. I’ll test my application tomorrow at the  
> > > office.
> > > 
> > > The only other thing hanging on is a string0.sats/dats, which is a copy  
> > > of string.sats/dats with modification used by hardware\_serial. I’ll leave  
> > > that up to Kiwamu, as he wrote the code.
> > > 
> > > Kiwamu,
> > > 
> > > We can talk over e-mail about what I did and the twi files/example. I  
> > > think decoupling from ATS2 CATS files will be much cleaner. I used your  
> > > Makefile changes to test this out and had no problems. So hopefully after  
> > > the next release we can remove the dependencies and CAT files, and I can  
> > > give yo the twi stuff.
> > 
> > –  
> > You received this message because you are subscribed to the Google Groups  
> > “ats-lang-users” group.  
> > To unsubscribe from this group and stop receiving emails from it, send an  
> > email to [ats-lang...@googlegroups.com](mailto:ats-lang...@googlegroups.com) \<javascript:\>.  
> > To post to this group, send email to [ats-l...@googlegroups.com](mailto:ats-l...@googlegroups.com)  
> > \<javascript:\>.  
> > Visit this group at [http://groups.google.com/group/ats-lang-users](http://groups.google.com/group/ats-lang-users).  
> > To view this discussion on the web visit  
> > [https://groups.google.com/d/msgid/ats-lang-users/0e9ea800-2e7a-45ed-9456-3279451c9592%40googlegroups.com](https://groups.google.com/d/msgid/ats-lang-users/0e9ea800-2e7a-45ed-9456-3279451c9592%40googlegroups.com)  
> > [https://groups.google.com/d/msgid/ats-lang-users/0e9ea800-2e7a-45ed-9456-3279451c9592%40googlegroups.com?utm\_medium=email&utm\_source=footer](https://groups.google.com/d/msgid/ats-lang-users/0e9ea800-2e7a-45ed-9456-3279451c9592%40googlegroups.com?utm_medium=email&utm_source=footer)  
> > .

---

<div class="post-metadata">

**Author:** ![Mike\_Jones](https://avatars.discourse-cdn.com/v4/letter/m/74df32/32.png) [@Mike\_Jones](https://discourse.ats-lang.org/u/Mike_Jones)\
**Post date:** [September 23, 2015, 3:14am UTC](https://discourse.ats-lang.org/t/fprintf-support-in-cats-files-effects-compilation-for-embedded-target/257/12 "2015-09-23T03:14:27Z")

</div>

I was able to change the arduino-ats prelude to all point to the ATS2  
distribution. Then remove all the files. Everything compiles including my  
application. 01\_blink works. I’ll test my application tomorrow at the  
office.

The only other thing hanging on is a string0.sats/dats, which is a copy of  
string.sats/dats with modification used by hardware\_serial. I’ll leave that  
up to Kiwamu, as he wrote the code.

Kiwamu,

We can talk over e-mail about what I did and the twi files/example. I think  
decoupling from ATS2 CATS files will be much cleaner. I used your Makefile  
changes to test this out and had no problems. So hopefully after the next  
release we can remove the dependencies and CAT files, and I can give yo the  
twi stuff.

---

<div class="post-metadata">

**Author:** ![gmhwxi](https://avatars.discourse-cdn.com/v4/letter/g/67e7ee/32.png) [@gmhwxi](https://discourse.ats-lang.org/u/gmhwxi)\
**Post date:** [September 20, 2015, 10:24pm UTC](https://discourse.ats-lang.org/t/fprintf-support-in-cats-files-effects-compilation-for-embedded-target/257/13 "2015-09-20T22:24:16Z")

</div>

To me, using a different set of CATS files for arduino-ats is a reasonable  
design for otherwise we may have to introduce a lot of #if-guards, which  
could  
be confusing (and likely harder to maintain).

Actually, it will be really good if someone can write a script for  
automatically generating  
CATS files targeting different platforms.On Sunday, September 20, 2015 at 5:17:26 PM UTC-4, Mike Jones wrote:

> There are two parts:
> 
> A) Undertand the compilation error and see if there is a work around, with  
> the goal of removing the copied/modifed versions of CATS files in  
> arduino-ats, because it will be hard to maintain a copy
> 
> B) See if there is reason for prelude/CATS/integer.cats and other cats  
> files to be modified in some way to remove stdio for those targets that  
> can’t support it. By remove, I don’t mean copy/modify, but to modify the  
> files for an ATS release.
> 
> I am basically saying that coupling the CATS files to IO too tightly makes  
> ATS difficult for embedded users and I am searching for a solution, because  
> for me ATS’s highest value is for embedded platforms.
> 
> On Sunday, September 20, 2015 at 10:39:04 AM UTC-6, gmhwxi wrote:
> 
> > To be honest, I am not yet clear as to what problem needs to be solved  
> > here.
> > 
> > I see that you have the following line in your code:
> > 
> > > > #include “prelude/CATS/integer.cats”
> > 
> > Is it that you want to modify prelude/CATS/integer.cats so that it could  
> > work  
> > with avr-cc?
> > 
> > On Sunday, September 20, 2015 at 11:10:20 AM UTC-4, Mike Jones wrote:
> > 
> > > Let me get a bit more specific about the error and see if you can help  
> > > make it work with the avr stdio.h
> > > 
> > > I changed the avr\_prelude like this, so that stdio.h is included before  
> > > the ats prelude.
> > > 
> > > #include “stdio.h”  
> > > #include “prelude/CATS/integer.cats”  
> > > #include “avr\_prelude/CATS/pointer.cats”  
> > > …
> > > 
> > > Basically, just try one file from the ats prelude. In the errors below,  
> > > I have used bold type where the caret points to the error.
> > > 
> > > The default avr stdio.h has:
> > > 
> > > The default stdio.h has:
> > > 
> > > struct \_\_file {  
> > > char _buf; /_ buffer pointer _/  
> > > unsigned char unget; /_ ungetc() buffer \*/  
> > > uint8\_t flags;  
> > > …
> > > 
> > > extern struct \_\_file \*\_\_iob;  
> > > #define stdin (\_\_iob[0])  
> > > #define stdout (\_\_iob[1])  
> > > #define stderr (\_\_iob[2])
> > > 
> > > Here is an example error from the compile:
> > > 
> > > In file included from …/…/avr\_prelude/kernel\_prelude.cats:7:0,  
> > > from hardware\_serial\_dats.c:57:  
> > > hardware\_serial\_dats.c: At top level:  
> > > /opt/ATS/ATS2-Postiats-0.2.2/prelude/CATS/integer.cats:980:47: error:  
> > > expected declaration specifiers or ‘…’ before ‘(’ token  
> > > #define atspre\_print\_int(x) atspre\_fprint\_int(_stdout_, (x))
> > > 
> > > hardware\_serial\_dats.c:2264:1: note: in expansion of macro  
> > > ‘atspre\_print\_int’  
> > > atspre\_print\_int(atstkind\_t0ype(atstype\_int) arg0)  
> > > ^
> > > 
> > > Now I change the definition to the following to remove the stdxx macros:
> > > 
> > > > > > extern struct \_\_file _stdin; /_ Standard input stream. \*/  
> > > > > > extern struct \_\_file _stdout; /_ Standard output stream. \*/  
> > > > > > extern struct \_\_file _stderr; /_ Standard error output  
> > > > > > stream. \*/
> > > 
> > > The error becomes:
> > > 
> > > In file included from  
> > > /home/mike/arduino-ats/avr\_prelude/kernel\_prelude.cats:8:0,  
> > > from hardware\_serial\_dats.c:57:  
> > > hardware\_serial\_dats.c: At top level:  
> > > /opt/ATS/ATS2-Postiats-0.2.2/prelude/CATS/integer.cats:980:55: error:  
> > > expected ‘)’ before ‘(’ token  
> > > #define atspre\_print\_int(x) atspre\_fprint\_int(stdout, _(x)_)
> > > 
> > > hardware\_serial\_dats.c:2264:1: note: in expansion of macro  
> > > ‘atspre\_print\_int’  
> > > atspre\_print\_int(atstkind\_t0ype(atstype\_int) arg0)  
> > > ^
> > > 
> > > My interpretation is the preprocessor can’t expand the nested macro, in  
> > > both cases.
> > > 
> > > I was mainly surprised at the error when using the modified stdio.h

---

<div class="post-metadata">

**Author:** ![Mike\_Jones](https://avatars.discourse-cdn.com/v4/letter/m/74df32/32.png) [@Mike\_Jones](https://discourse.ats-lang.org/u/Mike_Jones)\
**Post date:** [September 22, 2015, 1:39pm UTC](https://discourse.ats-lang.org/t/fprintf-support-in-cats-files-effects-compilation-for-embedded-target/257/14 "2015-09-22T13:39:22Z")

</div>

William,

I’ll have a look. Right now, I have the twi files from arduino 1.6.5 inside  
the arduino-ats tree, and and a modified version of the Linduino LT\_I2C. My  
application is running on the Linduino code, but I am going to try to move  
to the twi layer. I’ll look at what you have before I move the code.

It will take a while, because I want to try to remove the CATS files first,  
and there is a code update waiting for me.

The ideal would be to remove the copied code from arduino-ats as well and  
just layer over a standard arduino tree, but that will more work. Some of  
the arduino code required is C++, and the current arduino-ats code is a mix  
of arduino c and ats recoded arduino C++.

When I get a little farther I need to work with the owner of the code to  
coordinate inspections and merges, etc. However, I can provide the twi  
files and an example if anyone wants to use it.On Monday, September 21, 2015 at 11:20:49 AM UTC-6, William Blair wrote:

> If you’re interested, I worked on an ATS library for creating I2C  
> applications on AVRs a while back. It was mostly adapted from a couple of  
> Atmel application notes written in C. The code is in ATS1, but I would like  
> to revise it to possibly use session types for describing the protocols  
> devices implement on top of I2C.
> 
> overview:  
> [http://blogs.bu.edu/wdblair/2012/11/01/transactions-on-a-two-wire-bus/](http://blogs.bu.edu/wdblair/2012/11/01/transactions-on-a-two-wire-bus/)
> 
> interface:  
> [https://github.com/wdblair/avr-libats/blob/master/SATS/twi.sats](https://github.com/wdblair/avr-libats/blob/master/SATS/twi.sats)
> 
> Am Samstag, 19. September 2015 15:52:57 UTC-4 schrieb Mike Jones:
> 
> > I’m adding some I2C support to arduino-ats and decided to look under the  
> > hood to see why the arduino prelude uses modified versions of CATS files,  
> > and see if it would be possible to use the standard prelude for ATS2. It  
> > looks like the primary reason for copying CATS files, is to remove code  
> > related to stdio and printing.
> > 
> > This leads to some questions about how enable the embedded developers at  
> > the end of the discussion of things I tried to get around the problem.
> > 
> > Some discussion of things I tried…
> > 
> > As an experiment, I forced the inclusion of the avr version of stdio.h  
> > and it creates errors because stderr/out/in are macros, and the avr  
> > toolchain seems to have a problem with nested macros. As an experiment, I  
> > changed the stdio.h to have these definitions:
> > 
> > extern struct \_\_file _stdin; /_ Standard input stream. \*/  
> > extern struct \_\_file _stdout; /_ Standard output stream. \*/  
> > extern struct \_\_file _stderr; /_ Standard error output stream. \*/
> > 
> > Which removes the error and leaves the following error:
> > 
> > /opt/ATS/ATS2-Postiats-0.2.2/prelude/CATS/integer.cats:980:55: error:  
> > expected ‘)’ before ‘(’ token  
> > #define atspre\_print\_int(x) atspre\_fprint\_int(stdout, (x))
> > 
> > ```
> > ^
> > 
> > ```
> > 
> > In case of spacing in the text, the ^ is at (x)
> > 
> > The code called from this generated code in the .c file:
> > 
> > ATSextern()  
> > atsvoid\_t0ype  
> > atspre\_print\_int(atstkind\_t0ype(atstype\_int) arg0)  
> > {  
> > /\* tmpvardeclst(beg) \*/  
> > // ATStmpdec\_void(tmpret80) ;  
> > ATStmpdec(tmpref81[32], atstkind\_t0ype(atstype\_byte)) ;
> > 
> > I assume the compiler is bumping into a similar nested macro problem.
> > 
> > Back to the real question.
> > 
> > Stdio is not something always available when you are dealing with bare  
> > iron or RTOS based platforms, and often it is senseless. So I am asking how  
> > might this be addressed? My thoughts are that faking out ATS with functions  
> > that are not needed is a poor approach. I think it would make more sense to  
> > have a #define to either turn off everything related to stdio, or allow for  
> > user definitions, or both. Another approach might be to factor out the code  
> > into one file/interface so that an application can simply not include it.
> > 
> > In general, I think coupling any core libraries to IO or an OS API will  
> > limit the user base, if those libraries are essential to quick success.
> > 
> > Thoughts?
> > 
> > Mike

---

<div class="post-metadata">

**Author:** ![William\_Blair](https://avatars.discourse-cdn.com/v4/letter/w/c68b51/32.png) [@William\_Blair](https://discourse.ats-lang.org/u/William_Blair)\
**Post date:** [September 21, 2015, 5:20pm UTC](https://discourse.ats-lang.org/t/fprintf-support-in-cats-files-effects-compilation-for-embedded-target/257/15 "2015-09-21T17:20:48Z")

</div>

If you’re interested, I worked on an ATS library for creating I2C  
applications on AVRs a while back. It was mostly adapted from a couple of  
Atmel application notes written in C. The code is in ATS1, but I would like  
to revise it to possibly use session types for describing the protocols  
devices implement on top of I2C.

overview:  
[http://blogs.bu.edu/wdblair/2012/11/01/transactions-on-a-two-wire-bus/](http://blogs.bu.edu/wdblair/2012/11/01/transactions-on-a-two-wire-bus/)

interface:  
[https://github.com/wdblair/avr-libats/blob/master/SATS/twi.satsAm](https://github.com/wdblair/avr-libats/blob/master/SATS/twi.satsAm) Samstag, 19. September 2015 15:52:57 UTC-4 schrieb Mike Jones:

> I’m adding some I2C support to arduino-ats and decided to look under the  
> hood to see why the arduino prelude uses modified versions of CATS files,  
> and see if it would be possible to use the standard prelude for ATS2. It  
> looks like the primary reason for copying CATS files, is to remove code  
> related to stdio and printing.
> 
> This leads to some questions about how enable the embedded developers at  
> the end of the discussion of things I tried to get around the problem.
> 
> Some discussion of things I tried…
> 
> As an experiment, I forced the inclusion of the avr version of stdio.h and  
> it creates errors because stderr/out/in are macros, and the avr toolchain  
> seems to have a problem with nested macros. As an experiment, I changed the  
> stdio.h to have these definitions:
> 
> extern struct \_\_file _stdin; /_ Standard input stream. \*/  
> extern struct \_\_file _stdout; /_ Standard output stream. \*/  
> extern struct \_\_file _stderr; /_ Standard error output stream. \*/
> 
> Which removes the error and leaves the following error:
> 
> /opt/ATS/ATS2-Postiats-0.2.2/prelude/CATS/integer.cats:980:55: error:  
> expected ‘)’ before ‘(’ token  
> #define atspre\_print\_int(x) atspre\_fprint\_int(stdout, (x))
> 
> ```
> ^
> 
> ```
> 
> In case of spacing in the text, the ^ is at (x)
> 
> The code called from this generated code in the .c file:
> 
> ATSextern()  
> atsvoid\_t0ype  
> atspre\_print\_int(atstkind\_t0ype(atstype\_int) arg0)  
> {  
> /\* tmpvardeclst(beg) \*/  
> // ATStmpdec\_void(tmpret80) ;  
> ATStmpdec(tmpref81[32], atstkind\_t0ype(atstype\_byte)) ;
> 
> I assume the compiler is bumping into a similar nested macro problem.
> 
> Back to the real question.
> 
> Stdio is not something always available when you are dealing with bare  
> iron or RTOS based platforms, and often it is senseless. So I am asking how  
> might this be addressed? My thoughts are that faking out ATS with functions  
> that are not needed is a poor approach. I think it would make more sense to  
> have a #define to either turn off everything related to stdio, or allow for  
> user definitions, or both. Another approach might be to factor out the code  
> into one file/interface so that an application can simply not include it.
> 
> In general, I think coupling any core libraries to IO or an OS API will  
> limit the user base, if those libraries are essential to quick success.
> 
> Thoughts?
> 
> Mike

---

<div class="post-metadata">

**Author:** ![Mike\_Jones](https://avatars.discourse-cdn.com/v4/letter/m/74df32/32.png) [@Mike\_Jones](https://discourse.ats-lang.org/u/Mike_Jones)\
**Post date:** [September 20, 2015, 3:10pm UTC](https://discourse.ats-lang.org/t/fprintf-support-in-cats-files-effects-compilation-for-embedded-target/257/16 "2015-09-20T15:10:20Z")

</div>

Let me get a bit more specific about the error and see if you can help make  
it work with the avr stdio.h

I changed the avr\_prelude like this, so that stdio.h is included before the  
ats prelude.

#include “stdio.h”  
#include “prelude/CATS/integer.cats”  
#include “avr\_prelude/CATS/pointer.cats”  
…

Basically, just try one file from the ats prelude. In the errors below, I  
have used bold type where the caret points to the error.

The default avr stdio.h has:

The default stdio.h has:

struct \_\_file {  
char _buf; /_ buffer pointer _/  
unsigned char unget; /_ ungetc() buffer \*/  
uint8\_t flags;  
…

extern struct \_\_file \*\_\_iob;  
#define stdin (\_\_iob[0])  
#define stdout (\_\_iob[1])  
#define stderr (\_\_iob[2])

Here is an example error from the compile:

In file included from …/…/avr\_prelude/kernel\_prelude.cats:7:0,  
from hardware\_serial\_dats.c:57:  
hardware\_serial\_dats.c: At top level:  
/opt/ATS/ATS2-Postiats-0.2.2/prelude/CATS/integer.cats:980:47: error:  
expected declaration specifiers or ‘…’ before ‘(’ token  
#define atspre\_print\_int(x) atspre\_fprint\_int(_stdout_, (x))

hardware\_serial\_dats.c:2264:1: note: in expansion of macro  
‘atspre\_print\_int’  
atspre\_print\_int(atstkind\_t0ype(atstype\_int) arg0)  
^

Now I change the definition to the following to remove the stdxx macros:

> > > extern struct \_\_file _stdin; /_ Standard input stream. \*/  
> > > extern struct \_\_file _stdout; /_ Standard output stream. \*/  
> > > extern struct \_\_file _stderr; /_ Standard error output stream. \*/

The error becomes:

In file included from  
/home/mike/arduino-ats/avr\_prelude/kernel\_prelude.cats:8:0,  
from hardware\_serial\_dats.c:57:  
hardware\_serial\_dats.c: At top level:  
/opt/ATS/ATS2-Postiats-0.2.2/prelude/CATS/integer.cats:980:55: error:  
expected ‘)’ before ‘(’ token  
#define atspre\_print\_int(x) atspre\_fprint\_int(stdout, _(x)_)

hardware\_serial\_dats.c:2264:1: note: in expansion of macro  
‘atspre\_print\_int’  
atspre\_print\_int(atstkind\_t0ype(atstype\_int) arg0)  
^

My interpretation is the preprocessor can’t expand the nested macro, in  
both cases.

I was mainly surprised at the error when using the modified stdio.h

---

<div class="post-metadata">

**Author:** ![gmhwxi](https://avatars.discourse-cdn.com/v4/letter/g/67e7ee/32.png) [@gmhwxi](https://discourse.ats-lang.org/u/gmhwxi)\
**Post date:** [September 21, 2015, 11:56am UTC](https://discourse.ats-lang.org/t/fprintf-support-in-cats-files-effects-compilation-for-embedded-target/257/17 "2015-09-21T11:56:38Z")

</div>

I have just moved various fprint-functions out of  
integer.cats, bool.cats, char.cats, pointer.cats, string.cats. etc.  
Now you should be able use these CATS files in arduino-ats directly.On Monday, September 21, 2015 at 1:07:33 AM UTC-4, Mike Jones wrote:

> My concern is that different CATS files for the embedded world means 20+  
> of them to cover RTOS, SDKs, ARM/i386, etc.
> 
> A generator would be nice I suppose, but that can get complicated. I think  
> that just moves the complexity, but does not solve it. What happens when  
> the script generator creates code that does not compile and everyone blames  
> ATS?
> 
> I think it would be fine to have something like how memory is handled. You  
> can have MALLOC, GC, or user.
> 
> It would be a fair question to ask what about other couplings. From what I  
> have seen so far, there is not much coupling except stdio. Everything else  
> seems to be pure C.
> 
> On Sunday, September 20, 2015 at 4:24:17 PM UTC-6, gmhwxi wrote:
> 
> > To me, using a different set of CATS files for arduino-ats is a reasonable  
> > design for otherwise we may have to introduce a lot of #if-guards, which  
> > could  
> > be confusing (and likely harder to maintain).
> > 
> > Actually, it will be really good if someone can write a script for  
> > automatically generating  
> > CATS files targeting different platforms.
> > 
> > On Sunday, September 20, 2015 at 5:17:26 PM UTC-4, Mike Jones wrote:
> > 
> > > There are two parts:
> > > 
> > > A) Undertand the compilation error and see if there is a work around,  
> > > with the goal of removing the copied/modifed versions of CATS files in  
> > > arduino-ats, because it will be hard to maintain a copy
> > > 
> > > B) See if there is reason for prelude/CATS/integer.cats and other cats  
> > > files to be modified in some way to remove stdio for those targets that  
> > > can’t support it. By remove, I don’t mean copy/modify, but to modify the  
> > > files for an ATS release.
> > > 
> > > I am basically saying that coupling the CATS files to IO too tightly  
> > > makes ATS difficult for embedded users and I am searching for a solution,  
> > > because for me ATS’s highest value is for embedded platforms.
> > > 
> > > On Sunday, September 20, 2015 at 10:39:04 AM UTC-6, gmhwxi wrote:
> > > 
> > > > To be honest, I am not yet clear as to what problem needs to be solved  
> > > > here.
> > > > 
> > > > I see that you have the following line in your code:
> > > > 
> > > > > > #include “prelude/CATS/integer.cats”
> > > > 
> > > > Is it that you want to modify prelude/CATS/integer.cats so that it  
> > > > could work  
> > > > with avr-cc?
> > > > 
> > > > On Sunday, September 20, 2015 at 11:10:20 AM UTC-4, Mike Jones wrote:
> > > > 
> > > > > Let me get a bit more specific about the error and see if you can help  
> > > > > make it work with the avr stdio.h
> > > > > 
> > > > > I changed the avr\_prelude like this, so that stdio.h is included  
> > > > > before the ats prelude.
> > > > > 
> > > > > #include “stdio.h”  
> > > > > #include “prelude/CATS/integer.cats”  
> > > > > #include “avr\_prelude/CATS/pointer.cats”  
> > > > > …
> > > > > 
> > > > > Basically, just try one file from the ats prelude. In the errors  
> > > > > below, I have used bold type where the caret points to the error.
> > > > > 
> > > > > The default avr stdio.h has:
> > > > > 
> > > > > The default stdio.h has:
> > > > > 
> > > > > struct \_\_file {  
> > > > > char _buf; /_ buffer pointer _/  
> > > > > unsigned char unget; /_ ungetc() buffer \*/  
> > > > > uint8\_t flags;  
> > > > > …
> > > > > 
> > > > > extern struct \_\_file \*\_\_iob;  
> > > > > #define stdin (\_\_iob[0])  
> > > > > #define stdout (\_\_iob[1])  
> > > > > #define stderr (\_\_iob[2])
> > > > > 
> > > > > Here is an example error from the compile:
> > > > > 
> > > > > In file included from …/…/avr\_prelude/kernel\_prelude.cats:7:0,  
> > > > > from hardware\_serial\_dats.c:57:  
> > > > > hardware\_serial\_dats.c: At top level:  
> > > > > /opt/ATS/ATS2-Postiats-0.2.2/prelude/CATS/integer.cats:980:47: error:  
> > > > > expected declaration specifiers or ‘…’ before ‘(’ token  
> > > > > #define atspre\_print\_int(x) atspre\_fprint\_int(_stdout_, (x))
> > > > > 
> > > > > hardware\_serial\_dats.c:2264:1: note: in expansion of macro  
> > > > > ‘atspre\_print\_int’  
> > > > > atspre\_print\_int(atstkind\_t0ype(atstype\_int) arg0)  
> > > > > ^
> > > > > 
> > > > > Now I change the definition to the following to remove the stdxx  
> > > > > macros:
> > > > > 
> > > > > > > > extern struct \_\_file _stdin; /_ Standard input stream. \*/  
> > > > > > > > extern struct \_\_file _stdout; /_ Standard output stream. \*/  
> > > > > > > > extern struct \_\_file _stderr; /_ Standard error output  
> > > > > > > > stream. \*/
> > > > > 
> > > > > The error becomes:
> > > > > 
> > > > > In file included from  
> > > > > /home/mike/arduino-ats/avr\_prelude/kernel\_prelude.cats:8:0,  
> > > > > from hardware\_serial\_dats.c:57:  
> > > > > hardware\_serial\_dats.c: At top level:  
> > > > > /opt/ATS/ATS2-Postiats-0.2.2/prelude/CATS/integer.cats:980:55: error:  
> > > > > expected ‘)’ before ‘(’ token  
> > > > > #define atspre\_print\_int(x) atspre\_fprint\_int(stdout, _(x)_)
> > > > > 
> > > > > hardware\_serial\_dats.c:2264:1: note: in expansion of macro  
> > > > > ‘atspre\_print\_int’  
> > > > > atspre\_print\_int(atstkind\_t0ype(atstype\_int) arg0)  
> > > > > ^
> > > > > 
> > > > > My interpretation is the preprocessor can’t expand the nested macro,  
> > > > > in both cases.
> > > > > 
> > > > > I was mainly surprised at the error when using the modified stdio.h

---

<div class="post-metadata">

**Author:** ![gmhwxi](https://avatars.discourse-cdn.com/v4/letter/g/67e7ee/32.png) [@gmhwxi](https://discourse.ats-lang.org/u/gmhwxi)\
**Post date:** [September 23, 2015, 3:23pm UTC](https://discourse.ats-lang.org/t/fprintf-support-in-cats-files-effects-compilation-for-embedded-target/257/18 "2015-09-23T15:23:20Z")

</div>

As a rule of thumb, the C code generated by Patsopt in general needs to be  
compiled with -O2 to  
ensure that inlining is properly done.On Wed, Sep 23, 2015 at 11:15 AM, Mike Jones [proc...@gmail.com](mailto:proc...@gmail.com) wrote:

> My app runs, but it is suddenly very slow. I need to debug to see if it is  
> related to hardware, application code, or other.
> 
> On Tuesday, September 22, 2015 at 9:14:28 PM UTC-6, Mike Jones wrote:
> 
> > I was able to change the arduino-ats prelude to all point to the ATS2  
> > distribution. Then remove all the files. Everything compiles including my  
> > application. 01\_blink works. I’ll test my application tomorrow at the  
> > office.
> > 
> > The only other thing hanging on is a string0.sats/dats, which is a copy  
> > of string.sats/dats with modification used by hardware\_serial. I’ll leave  
> > that up to Kiwamu, as he wrote the code.
> > 
> > Kiwamu,
> > 
> > We can talk over e-mail about what I did and the twi files/example. I  
> > think decoupling from ATS2 CATS files will be much cleaner. I used your  
> > Makefile changes to test this out and had no problems. So hopefully after  
> > the next release we can remove the dependencies and CAT files, and I can  
> > give yo the twi stuff.
> 
> –  
> You received this message because you are subscribed to the Google Groups  
> “ats-lang-users” group.  
> To unsubscribe from this group and stop receiving emails from it, send an  
> email to [ats-lang-user...@googlegroups.com](mailto:ats-lang-user...@googlegroups.com).  
> To post to this group, send email to [ats-lan...@googlegroups.com](mailto:ats-lan...@googlegroups.com).  
> Visit this group at [http://groups.google.com/group/ats-lang-users](http://groups.google.com/group/ats-lang-users).  
> To view this discussion on the web visit  
> [https://groups.google.com/d/msgid/ats-lang-users/0e9ea800-2e7a-45ed-9456-3279451c9592%40googlegroups.com](https://groups.google.com/d/msgid/ats-lang-users/0e9ea800-2e7a-45ed-9456-3279451c9592%40googlegroups.com)  
> [https://groups.google.com/d/msgid/ats-lang-users/0e9ea800-2e7a-45ed-9456-3279451c9592%40googlegroups.com?utm\_medium=email&utm\_source=footer](https://groups.google.com/d/msgid/ats-lang-users/0e9ea800-2e7a-45ed-9456-3279451c9592%40googlegroups.com?utm_medium=email&utm_source=footer)  
> .

---

<div class="post-metadata">

**Author:** ![Mike\_Jones](https://avatars.discourse-cdn.com/v4/letter/m/74df32/32.png) [@Mike\_Jones](https://discourse.ats-lang.org/u/Mike_Jones)\
**Post date:** [September 26, 2015, 2:46pm UTC](https://discourse.ats-lang.org/t/fprintf-support-in-cats-files-effects-compilation-for-embedded-target/257/19 "2015-09-26T14:46:40Z")

</div>

Kiwamu,

Attached is a patch that has twi, smbus, and changes the prelude, plus  
removal of cats files.

You already updated the makefile for the new release.

I tested 01\_blink. Others compile, but I did not test them.

The i2c/smbus demos are specific to my PMBus hardware. If there is some  
standard shield everyone uses a lot, they could be modified for a more  
common hardware.

Mike

The twi files are from arduinoOn Thursday, September 24, 2015 at 1:29:33 AM UTC-6, Kiwamu Okabe wrote:

> Hi Mike,  
> sorry for too late reply.
> 
> On Wed, Sep 23, 2015 at 12:14 PM, Mike Jones \<[pro...@gmail.com](mailto:pro...@gmail.com) \<javascript:\>\> wrote:
> 
> > We can talk over e-mail about what I did and the twi files/example. I  
> > think  
> > decoupling from ATS2 CATS files will be much cleaner. I used your  
> > Makefile  
> > changes to test this out and had no problems. So hopefully after the  
> > next  
> > release we can remove the dependencies and CAT files, and I can give yo  
> > the  
> > twi stuff.
> 
> I think I can merge it into my repo.  
> Could you show me the running code?
> 
> ## Thank’s,
> 
> Kiwamu Okabe at METASEPI DESIGN

[ats23.patch](https://us1.discourse-cdn.com/flex019/uploads/ats_lang/original/1X/461ac1285daa253fd7f5ea9fca8e777d7cbf89e2.patch) (142 KB)

---

<div class="post-metadata">

**Author:** ![Mike\_Jones](https://avatars.discourse-cdn.com/v4/letter/m/74df32/32.png) [@Mike\_Jones](https://discourse.ats-lang.org/u/Mike_Jones)\
**Post date:** [September 23, 2015, 3:15pm UTC](https://discourse.ats-lang.org/t/fprintf-support-in-cats-files-effects-compilation-for-embedded-target/257/20 "2015-09-23T15:15:03Z")

</div>

My app runs, but it is suddenly very slow. I need to debug to see if it is  
related to hardware, application code, or other.On Tuesday, September 22, 2015 at 9:14:28 PM UTC-6, Mike Jones wrote:

> I was able to change the arduino-ats prelude to all point to the ATS2  
> distribution. Then remove all the files. Everything compiles including my  
> application. 01\_blink works. I’ll test my application tomorrow at the  
> office.
> 
> The only other thing hanging on is a string0.sats/dats, which is a copy of  
> string.sats/dats with modification used by hardware\_serial. I’ll leave that  
> up to Kiwamu, as he wrote the code.
> 
> Kiwamu,
> 
> We can talk over e-mail about what I did and the twi files/example. I  
> think decoupling from ATS2 CATS files will be much cleaner. I used your  
> Makefile changes to test this out and had no problems. So hopefully after  
> the next release we can remove the dependencies and CAT files, and I can  
> give yo the twi stuff.