A tiny Raspberry Pico and Pico2 shell with flash file system, Vi, and C compiler.
This project explores to what extent a reasonably competent self-hosted programming environment can be built on a modern embedded SoC.
Credit where credit is due...
- The vi code is ported from the BusyBox source code.
- The compiler code is a remix of the amacc compiler parser generator and the c4 virtual machine. Many important amacc enhancements such as floating point, array, struct and type checking support were taken fom the Squint project.
- Native machine code generation for CM0 and CM33 by Jean M. Cyr.
- Console command recall and auto completion by Eric Olson.
What's new in pshell
About the compiler, briefly:
- Data types: integer, float, char and pointer.
- Aggregate types: array (up to 3 dimensions), struct and union.
- Flow control: for, while, if then else, break, continue, switch and goto.
- Memory, math, newlib and SDK functions. (list of implemented functions)
- Native code generation for the Pico's cm0+ and pico2 cm33 cores.
Raspberry Pi Forums thread.
Discussion area.
Building from source for the RP2040.
# NOTE: Requires sdk 1.4 or later
git clone --recursive https://github.com/lurk101/pshell.git
cd pshell
mkdir build
cd build
cmake .. -DPICO_BOARD=pico -DPICO_PLATFORM=rp2040
make
Building from source for the RP2350.
# NOTE: Requires sdk 2.0 or later
git clone --recursive https://github.com/lurk101/pshell.git
cd pshell
mkdir build
cd build
cmake .. -DPICO_BOARD=pico2 -DPICO_PLATFORM=rp2350
make
For UART console, add the following cmake command parameter.
-DUSB_CONSOLE=OFF
For vgaboard with filesystem on microSD card. See here for details on differing GPIO & UART configurations.
cmake .. -DPICO_BOARD=vgaboard -DPICO_PLATFORM=rp2040
Starting with version 1.0.4 all development will occur on the dev branch. To build it:
git checkout dev
Git branches
- master: stable release branch
- dev: development and fix branch
- vm: legacy virtual machine branch (no longer under active development)
If you want to build from a different branch you can switch to it with
git checkout branch-name
C source code examples.
Example console log.
Pico Shell - Copyright (c) 1883 Thomas Edison
This program comes with ABSOLUTELY NO WARRANTY.
This is free software, and you are welcome to redistribute it
under certain conditions. See LICENSE file for details.
platform: pico2, console: UART0 [94 X 31], filesystem: flash
enter command or hit ENTER for help
file system automatically mounted
/: version
Pico Shell v2.1.2, LittleFS v2.9, Vi 0.9.1, SDK v2.0.0
/: ls
343 blink.c
364 clocks.c
120 crash.c
1026 crc16.c
3941 day8.c
17071 day8.txt
2308 doughnut.c
171 exit.c
976 fade.c
175 forward.c
69 hello.c
1344 io.c
2221 life.c
5423 lorenz.c
1951 penta.c
215 pi.c
249 printf.c
1328 qsort.c
2631 rndtest.c
536 sieve.c
373 sine.c
673 string.c
1265 testfloat.c
1135 testint.c
297 tictoc.c
10192 wumpus.c
/: cc sine.c
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
CC = 0
/: cc -s sine.c
1: /* Math function test. Display a sine wave */
2:
3: int main() {
4: int angle, incr;
5: for (incr = 16, angle = 0; angle <= 360; angle += incr) {
6: float rad = (float)angle * 0.01745329252;
7: printf("%.*s%c\n", 30 + (int)(sinf(rad) * 25.0),
8: " ;
9: }
10: return 0;
11: }
20078000 b580 push {r7, lr}
20078002 466f mov r7, sp
20078004 b083 sub sp, #12 ; 0xc
20078006 463b mov r3, r7
20078008 3b08 subs r3, #8
2007800a 2010 movs r0, #16 ; 0x10
2007800c 6018 str r0, [r3, #0]
2007800e 1f38 subs r0, r7, #4
20078010 b401 push {r0}
20078012 2000 movs r0, #0
20078014 bc08 pop {r3}
20078016 6018 str r0, [r3, #0]
20078018 f000 f843 bl 200780a2
2007801c 4638 mov r0, r7
2007801e 380c subs r0, #12 ; 0xc
20078020 b401 push {r0}
20078022 1f38 subs r0, r7, #4
20078024 edd0 7a00 vldr s15, [r0, #0]
20078028 eef8 7ae7 vcvt s15, s15
2007802c ee17 0a90 vmov r0, s15
20078030 b401 push {r0}
20078032 4824 ldr r0, [pc, #144] ; 0x200780c4
20078034 ee07 0a90 vmov s15, r0
20078038 ecbd 7a01 vpop {s14}
2007803c ee67 7a27 vmul s15, s14, s15
20078040 ee17 0a90 vmov r0, s15
20078044 bc08 pop {r3}
20078046 6018 str r0, [r3, #0]
20078048 481f ldr r0, [pc, #124] ; 0x200780c8
2007804a b401 push {r0}
2007804c 201e movs r0, #30 ; 0x1e
2007804e b401 push {r0}
20078050 4638 mov r0, r7
20078052 380c subs r0, #12 ; 0xc
20078054 6800 ldr r0, [r0, #0]
20078056 4b1d ldr r3, [pc, #116] ; 0x200780cc
20078058 4798 blx r3
2007805a b401 push {r0}
2007805c 481c ldr r0, [pc, #112] ; 0x200780d0
2007805e ee07 0a90 vmov s15, r0
20078062 ecbd 7a01 vpop {s14}
20078066 ee67 7a27 vmul s15, s14, s15
2007806a ee17 0a90 vmov r0, s15
2007806e eefd 7ae7 vcvt.s32 s15, s15
20078072 ee17 0a90 vmov r0, s15
20078076 bc08 pop {r3}
20078078 18c0 adds r0, r0, r3
2007807a b401 push {r0}
2007807c 4815 ldr r0, [pc, #84] ; 0x200780d4
2007807e b401 push {r0}
20078080 202a movs r0, #42 ; 0x2a
20078082 b401 push {r0}
20078084 2004 movs r0, #4
20078086 4b14 ldr r3, [pc, #80] ; 0x200780d8
20078088 4798 blx r3
2007808a b004 add sp, #16 ; 0x10
2007808c 1f38 subs r0, r7, #4
2007808e b401 push {r0}
20078090 6800 ldr r0, [r0, #0]
20078092 b401 push {r0}
20078094 4638 mov r0, r7
20078096 3808 subs r0, #8
20078098 6800 ldr r0, [r0, #0]
2007809a bc08 pop {r3}
2007809c 18c0 adds r0, r0, r3
2007809e bc08 pop {r3}
200780a0 6018 str r0, [r3, #0]
200780a2 1f38 subs r0, r7, #4
200780a4 6800 ldr r0, [r0, #0]
200780a6 b401 push {r0}
200780a8 480c ldr r0, [pc, #48] ; 0x200780dc
200780aa bc02 pop {r1}
200780ac 4281 cmp r1, r0
200780ae bfcc ite gt
200780b0 2000 movgt r0, #0
200780b2 2001 movle r0, #1
200780b4 2800 cmp r0, #0
200780b6 d1b1 bne 2007801c
200780b8 2000 movs r0, #0
200780ba 46bd mov sp, r7
200780bc bd80 pop {r7, pc}
200780be 46bd mov sp, r7
200780c0 bd80 pop {r7, pc}
200780c2 46c0 mov r8, r8
200780c4 3c8e fa35 .word 0x3c8efa35
200780c8 2007 c000 .word 0x2007c000
200780cc 1002 2b31 .word 0x10022b31 ; sinf
200780d0 41c8 0000 .word 0x41c80000
200780d4 2007 c008 .word 0x2007c008
200780d8 1001 520d .word 0x1001520d ; printf
200780dc 0000 0168 .word 0x00000168
200780e0 0000 0000 .word 0x00000000 ; "\0\0\0\0"
11:
/:
cat - display a text file, use -p to paginate
cc - compile & run C source file. cc -h for help
cd - change directory
clear - clear the screen
cp - copy a file
format - format the filesystem
hex - simple hexdump, use -p to paginate
ls - list a directory, -a to show hidden files
mkdir - create a directory
mount - mount the filesystem
mv - rename a file or directory
quit - shutdown the system
reboot - restart the system
resize - establish screen dimensions
rm - remove a file or directory. -r for recursive
status - display the filesystem status
tar - manage tar archives
unmount - unmount the filesystem
version - display pico shell's version
vi - edit file(s) with vi
xget - get a file (xmodem, pico->host)
xput - put a file (xmodem, host->pico)
yget - get a file (ymodem, pico->host)
yput - put a file (ymodem, host->pico)
/:
