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bfwolf
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Joined: 03/01/2025
Location: Germany
Posts: 270

Posted: 11:56am 05 Nov 2026

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I think, this will be an interesting possibility:

https://www.thebackshed.com/forum/ViewTopic.php?TID=19209&P=1#260985

"4. Use C functions inside BASIC (RP2350 only). Write a CSUB in C instead of manually creating hexadecimal machine code. PicoMite compiles it when saving the BASIC program. The CSUB then runs directly from flash. Example: C CSUB"
https://github.com/DnCraptor/pico-mm/blob/tcc/Bas/pm_library_csub_tcc.bas

ville56
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Joined: 08/06/2022
Location: Austria
Posts: 665

Posted: 02:19pm 05 Nov 2026

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Please help a C beginner ... what's wrong here?

>
> list "x.c
#include <stdio.h>
int main(int argc, char **argv)
{
printf("Hello from C, argc=%d\n", argc);
For (int i = 1; i < argc; i++)
printf(" argv[%d] = %s\n", i, argv[i]);
Return 0;
}
>
>
> run "x.c
x.c:6: warning: implicit declaration of function 'For'
x.c:6: error: identifier expected
Error : C compilation failed
>

Tnx,
Gerald

73 de OE1HGA, Gerald

MikeV73
Regular Member

Joined: 03/07/2025
Location: Ukraine
Posts: 42

Posted: 02:24pm 05 Nov 2026

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ville56 said Please help a C beginner ... what's wrong here?

>
> list "x.c
#include <stdio.h>
int main(int argc, char **argv)
{
printf("Hello from C, argc=%d\n", argc);
For (int i = 1; i < argc; i++)
printf(" argv[%d] = %s\n", i, argv[i]);
Return 0;
}
>
>
> run "x.c
x.c:6: warning: implicit declaration of function 'For'
x.c:6: error: identifier expected
Error : C compilation failed
>

Tnx,
Gerald

capitalisation. C is case secisitive lang.
it should be "for", not "For", and "return", not "Return"

ville56
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Joined: 08/06/2022
Location: Austria
Posts: 665

Posted: 02:31pm 05 Nov 2026

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ouch ... thank you.

Had a C/C++ course 30 years ago. Used it only once in 1999 to get a DCF77 NTP server Y2k ready which the vendor refused to do saying it was impossible. Was rather trivial then. But now all memories of C have faded away.

73 de OE1HGA, Gerald

MikeV73
Regular Member

Joined: 03/07/2025
Location: Ukraine
Posts: 42

Posted: 04:02pm 05 Nov 2026

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UPD:
+ RC3: https://github.com/DnCraptor/pico-mm/releases/tag/PicoMite-V7.0.00b8-tcc-elf-RC3

What's new since RC2

1. Resident keyboard remapping
- New C API for remapping physical keyboard input (PS/2 and USB).
- Key press, release, repeat and modifier events.
- Callbacks remain active across BASIC RUN and END.
- New printable-character classification hook for console, EDIT and FM.

2. Russian keyboard support (KeyRus)
- Resident EN/RU keyboard remapper using Windows-1251.
- Ctrl+Shift switches between layouts.
- Includes an 8x16 Cyrillic font (#10).
- Works on RP2350 (TinyCC) and RP2040 (precompiled ELF).
- Includes install, start and stop scripts.
- Supports automatic startup with OPTION AUTORUN ON.

Source: KeyRus files and examples

3. C syntax highlighting in EDIT
- Syntax colours for .c and .h files.
- Keywords, directives, comments, strings and numbers.
- Recognises native PicoMite C API functions.
- Different colours for functions unavailable or restricted in CSUB.
- Works on the local display and ANSI terminals.

4. Console font API
- Added pm_set_console_font() for resident-controlled console fonts.
- Custom fonts can be used in the console and EDIT.
- Fixed lost FM colours when using custom fonts in video mode 1.

Bug fixes

- OPTION LOGGING no longer writes extra bytes or garbage after error messages (#139).
- MM.INFO(USB VID/PID n) now returns 0 for unused channels (#142).
- PLAY TONE and PLAY SOUND now play at the correct speed and pitch after WAV/MOD playback or a USB connection sound (#145).
- Fixed Python detection when embedding TinyCC headers during RP2350 builds.

Native C API

Updated to API v35, adding keyboard remapping, printable-character classification and console font control.

KeyRus quick start

Copy the KeyRus files to the PicoMite filesystem, then run:

RUN "key_rus_install.bas"

To stop:

RUN "key_rus_stop.bas"

To enable automatic startup, load key_rus_start.bas into the program memory and use:

OPTION AUTORUN ON

Changes since RC2

Full comparison: RC2 to RC3

RC3 source commit: 67a9e5477
Edited 2026-11-06 02:06 by MikeV73

MikeV73
Regular Member

Joined: 03/07/2025
Location: Ukraine
Posts: 42

Posted: 04:07pm 05 Nov 2026

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Actually, any language may be provided, and russian with cp1251 - just techno demo.

PhenixRising
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Joined: 07/11/2023
Location: United Kingdom
Posts: 2149

Posted: 04:14pm 05 Nov 2026

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ville56 said ouch ... thank you.

Had a C/C++ course 30 years ago. Used it only once in 1999 to get a DCF77 NTP server Y2k ready which the vendor refused to do saying it was impossible. Was rather trivial then. But now all memories of C have faded away.

I just take MMBasic code and have Gemini translate to C

I also set:

Quote >OPTION CASE LOWER

ville56
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Joined: 08/06/2022
Location: Austria
Posts: 665

Posted: 04:39pm 05 Nov 2026

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nah, want to write my own C code in the first place. AI may come later after I have understood C a bit more.
But tnx for the hint with option case lower.

73 de OE1HGA, Gerald

ville56
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Joined: 08/06/2022
Location: Austria
Posts: 665

Posted: 08:36pm 06 Nov 2026

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MikeV73,

I think there is some instability in FM in your latest build. FM crashes when selecting and deleting files, sometimes just when navigating.

Example:

208 x.c | 207 x.cmd
208 x.c.bak | 202 x.cmd.bak
207 x.cmd | 67 y.cmd
202 x.cmd.bak | 67 y.cmd.bak
67 y.cmd | 66 z.cmd
67 y.cmd.bak |
66 z.cmd |*** FAULT PC=100069FC LR=100069D5 SP=200808E0 CFSR=00008200 HFSR=40000000
*** FAULT R0=01000000 R1=00000000 R2=0000000C R3=40828000 R12=00000180 XPSR=09100000 FAR=40828230 EXC=FFFFFFE9
Total of 5 Mbytes PSRAM available

In the example above, there were A: and B: drive used. The same FM operations with the latest MMBasic version from Peter has no issues insofar.

Environment:
PicoMitePC3 MMBasic USB RP2350B Edition V7.00.00RC7
OPTION SERIAL CONSOLE COM2,GP8,GP9
OPTION SYSTEM I2C GP20,GP21
OPTION FLASH SIZE 16777216
OPTION COLOURCODE ON
OPTION CASE LOWER
OPTION KEYBOARD GR
OPTION HEARTBEAT OFF
OPTION PICO OFF
OPTION RESOLUTION 1280x720 @ 372000KHz
OPTION DISPLAY 30, 80
OPTION HDMI PINS 1, 3, 5, 7
OPTION WIFI JN88fg, *********, PC3-2
OPTION SDCARD GP33, GP30, GP31, GP28
OPTION AUDIO I2S GP10,GP22', ON PWM CHANNEL 11
OPTION RTC AUTO ENABLE
OPTION COUNT GP34,GP35,GP36,GP37
OPTION COMPILE ON
OPTION PLATFORM PICO COMPUTER 3
OPTION DEFAULT FONT 3, 1
OPTION PSRAM PIN GP47

Gerald

73 de OE1HGA, Gerald

MikeV73
Regular Member

Joined: 03/07/2025
Location: Ukraine
Posts: 42

Posted: 11:26pm 06 Nov 2026

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ville56 said MikeV73,

I think there is some instability in FM in your latest build. FM crashes when selecting and deleting files, sometimes just when navigating.

...
Gerald

Thanks, Gerald, for the detailed report!

The fault information is very useful. Could you please clarify a few things?

1. Which exact UF2 build are you testing? A filename or download link would help.
2. Does FM crash on A: only, B: only, or both? Does it happen while navigating, selecting a file, or confirming deletion?
3. Can you reproduce it reliably, or does it happen randomly?
4. Does it still happen with `OPTION COMPILE OFF` after reboot?
5. If possible, could you also try a lower CPU speed (252 or 315 MHz) and see whether the crashes persist?

The fault points to an invalid memory access. I will also check PC `0x100069FC` against the matching ELF/map file.

Thanks again for testing!

ville56
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Joined: 08/06/2022
Location: Austria
Posts: 665

Posted: 08:47am 07 Nov 2026

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1. Which exact UF2 build are you testing? A filename or download link would help.
from RC3: https://github.com/DnCraptor/pico-mm/releases/tag/PicoMite-V7.0.00b8-tcc-elf-RC3
filename is PicoMite-PC3.uf2 as it is running on a PC3

2. Does FM crash on A: only, B: only, or both? Does it happen while navigating, selecting a file, or confirming deletion?
on both, crashes with every action sometimes. Tried with mark, copy, delete, navigation. Mark (spave key) is the one to go with as it crashes almost certainly somewhere in a list of abt 20 files. Does it on A: and B:

3. Can you reproduce it reliably, or does it happen randomly?
completely randomly. But if I mark a list of files on drive A: one by one with the space key it almost certainly can be reproduced.

4. Does it still happen with `OPTION COMPILE OFF` after reboot?
yes

5. If possible, could you also try a lower CPU speed (252 or 315 MHz) and see whether the crashes persist?
tried with OPTION RESOLUTION 640x480 @ 252000KHz but still crashes.

Also tried with WIFI and PSRAM disabled, no success, still crashes.

Will try later today on other hardware (Pimoroni Pico plus 2W) in a minimal config to see if this is specific to my PC3 hardware.

EDIT:
on the Pimoroni FM does not crash but just hangs. Could only try with mark and run as I do only have A: drive there.
Hangs randomly on mark and also on run (enter key) for a .bas file. Can only be revived with reset button.

Build is PicoMite-WEBRP2350.uf2 in minimum config, no options set, 200MHz.

EDIT2:
can be reproduced by just starting FM, navigating a few files up and down (cursor keys) and exiting FM with esc -> Hangs.

EDIT3:
seems not to happen on a genue Pi pico with RP2040 chip (no WiFi)

EDIT4:
does not happen on plain RP2350 chip either (no WiFi)

So after all I suppose it may be connected to the WIFI part even if not in use/not configured.
Edited 2026-11-07 19:38 by ville56

73 de OE1HGA, Gerald

MikeV73
Regular Member

Joined: 03/07/2025
Location: Ukraine
Posts: 42

Posted: 09:45am 07 Nov 2026

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ville56 said
...

Thnx. efcbeb5.zip attached contains a fix for stack usage. Pls. try it.

efcbeb5.zip

ville56
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Joined: 08/06/2022
Location: Austria
Posts: 665

Posted: 10:12am 07 Nov 2026

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MikeV73 said
Thnx. efcbeb5.zip attached contains a fix for stack usage. Pls. try it.

efcbeb5.zip

Looks good!!!

Tried on RP2350 with Wifi off and on, Telnet console and PSRAM. No issues other than getting double >

>
>

as prompt over telnet. No hangs or crashes anymore.

Don't have time now to also test the 2040 build, will be later today.

Gerald

73 de OE1HGA, Gerald

MikeV73
Regular Member

Joined: 03/07/2025
Location: Ukraine
Posts: 42

Posted: 10:17am 07 Nov 2026

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ville56 said

MikeV73 said
Thnx. efcbeb5.zip attached contains a fix for stack usage. Pls. try it.

efcbeb5.zip

Thnx a lot. So, it was stack overflow issue. Will provide RC4 today for other platforms.

MikeV73
Regular Member

Joined: 03/07/2025
Location: Ukraine
Posts: 42

Posted: 10:54am 07 Nov 2026

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UPD:
+ RC4: https://github.com/DnCraptor/pico-mm/releases/tag/PicoMite-V7.0.00b8-tcc-elf-RC4

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