Mecrisp-Cube, Forth for the STM32 Ecosystem

Intro

Mecrisp-Stellaris Forth for the STM32 Cube ecosystem.

Forth is an interactive and extensible language, with built-in lexical analysis (tokenizer, parser) and compiler, needs less than 20 KiB Flash and 4 KiB RAM, unbelievable for a self-contained (self-hosted) system.

Forth is perfect for embedded systems where some sort of user interactivity like CLI and extensibility (at runtime) are needed.

C & Forth in the 21st Century. C and Forth are both about 50 years old. To combine the strength of this two worlds results in powerful system that outperforms other much newer systems like Python.

Sources on GitHub.

ForthSTM32WB Standard Mecrisp-Stellaris for STM32WB.

McForth Rc/Forth for the Membership Card, FIG-Forth - CDP1802 IP - Lattice FPGA-Board

USB, BLE and other Middlewares

STM32WB Forth without BLE, USB, Filesystems, RTOS etc. is not complete, to build this by myself from the scratch overwhelms me. I would like to go the reverse way and use the STM tools like CubeIDE, HAL, CubeMX and integrate the Mecrips Forth into it. Forth as an interactive extension for the STM ecosystem. Mecrisp Forth running as a CMSIS-RTOS thread.

Already done

Integrated in STM32 Cube ecosystem
Forth as CMSIS-RTOS thread
Buffered console IO (20 KiB for UART Rx)
USB-CDC for serial communication. Redirect console IO like usb_emit, usb_key
Board Support Package BSP
- LEDs
- switches
Using CMSIS-RTOS from Forth

Planned

BSP
- Digital port pins D0 to D15
- Analog port pins A0 to A5
- PWM
- I2C
USB-MSC to make it possible to read and write blocks or include source files. INCLUDE vs BLOCK? Forth source files
Command line editing like Gforth
BLE 5.0
- BLE vSP profile is proprietary, there is no standard serial communication profile. Redirect console IO like ble_emit, ble_key
- BLE Event driven programming like LAIRD's smartBASIC, WAITEVENT ONEVENT.
- BLE GATT (Characteristics, Services, Profiles)
Watchdog
Low power
Calling HAL and other C functions
Calling forth words form C (crawling through the dictionary)
Support for the floating point unit, CMSIS-DSP
UML state machine (extended state machine, hierarchically nested states)

Getting Started

These instructions will get you a copy of the project up and running on your local machine (STM32 Nucleo board) for development and testing purposes.

Prerequisites

STM32WB Nucleo Board - The highly affordable STM32 Nucleo boards allow anyone to try out new ideas and to quickly create prototypes with any STM32 MCU. The STM32 Nucleo boards integrate an ST-Link debugger/programmer, so there is no need for a separate probe.
Terminal emulator application for PC, e.g.:
- PuTTY - Windows and Linux
- Tera Term - Windows
- Realterm - Windows
- minicom, microcom, screen - Linux
- Use the built in Eclipse console (but no LF)

Flash the Mecrisp-Cube binary to the Nucleo Board.

Connect the Nucleo Board USB ST-LINK to the PC
Copy binary (minimal.bin) to the USB mass storage NODE_WB55RG

Start the terminal emulator application on the PC. Check for the serial communication port (e.g. for Linux /dev/ttyACM0) and set the speed to 115200 baud. I set the putty terminal configuration to

Implicit CR in every LF
Local echo: Auto
Local line editing: Auto

Mecrisp-Stellaris 2.5.2 for STM32WB55 by Matthias Koch
23 5 / .[CR] 4  ok.
: hello ." World" ;[CR]  ok.
hello[CR] World ok.

Installing

A step by step series of examples that tell you how to get a development env running

Install the IDE STM32CubeIDE, it is Eclipse and GCC based. STM32CubeMX is included in the IDE, you need a stand alone installation only if you do not want to use the STM32CubeIDE.

Get the sources from github:

psi@homer:~> git clone https://github.com/spyren/Mecrisp-Cube
Klone nach 'Mecrisp-Cube' ...
remote: Enumerating objects: 106, done.
remote: Counting objects: 100% (106/106), done.
remote: Compressing objects: 100% (71/71), done.
remote: Total 106 (delta 33), reused 106 (delta 33), pack-reused 0
Empfange Objekte: 100% (106/106), 938.96 KiB | 2.39 MiB/s, Fertig.
Löse Unterschiede auf: 100% (33/33), Fertig.

Import the project into the IDE:

File -> Import -> General -> Existing Projects into Workspace -> Select root directory
Copy project into workspace
Browse to Mecrisp-Cube directory

Generate code from the STM32CubeMX minimal.ioc file:

Project -> Generate Code

Select the Build Configuration (Debug if you want to debug the project) and Build the project:

Project -> Build Configurations -> Set Active -> Debug/Reelease 
Project -> Build Project

STM32WB Nucleo Board

Arduino Uno Pinout Guide

Built With

STM32CubeIDE is an all-in-one multi-OS development tool, which is part of the STM32Cube software ecosystem. The IDE is used for development, GCC tools are included.
STM32CubeMX is a graphical tool that allows a very easy configuration of STM32 microcontrollers and microprocessors, as well as the generation of the corresponding initialization C code for the Arm® Cortex®-M core or a partial Linux® Device Tree for Arm® Cortex®-A core), through a step-by-step process.
STM32CubeProg is an all-in-one multi-OS software tool for programming STM32 products. the Java GUI does not work for me, but the CLI does. See STM Wiki

Flash Mecrisp-Cube to the Target

Alternate ways to flash Mecrisp-Cube to the target.

Nucleo Board

Connect Nucleo's ST-LINK USB to you PC. Erase the flash e.g. by openOCD, we use 768 KiB 192 sectors.

$ telnet localhost 4444
Trying ::1...
telnet: connect to address ::1: Connection refused
Trying 127.0.0.1...
Connected to localhost.
Escape character is '^]'.
Open On-Chip Debugger
> reset init
Unable to match requested speed 500 kHz, using 480 kHz
Unable to match requested speed 500 kHz, using 480 kHz
target halted due to debug-request, current mode: Thread 
xPSR: 0x01000000 pc: 0x08003aae msp: 0x20000430
> flash erase_sector 0 0 192
erased sectors 0 through 192 on flash bank 0 in 4.583453s
> flash write_image mecrisp-stellaris-stm32wb55.hex
device idcode = 0x20016495 (STM32WB5x - Rev: 2.1)
flash size = 1024kbytes
flash mode : single-bank
Padding 4 bytes to keep 8-byte write size
block write succeeded
wrote 15404 bytes from file mecrisp-stellaris-stm32wb55.hex in 0.329747s (45.620 KiB/s)

> shutdown
shutdown command invoked
Connection closed by foreign host.

USB Dongle

The USB Dongle does not have a ST-Link interface, but the STM32WB has a built-in boot-loader. This bootloader works over USB. As programmer I use the CLI from the STM32CubeProg package.

$ alias cubepgmcli='/opt/STMicroelectronics/STM32Cube/STM32CubeProgrammer/bin/STM32_Programmer_CLI'
$ cubepgmcli -c port=USB1 -ob displ

BTW you can flash the Nucleo Board in the same way.

Update BLE Stack

You can find the BLE Stack and FUS in STM32CubeWB, in the directory Projects/STM32WB_Copro_Wireless_Binaries.

Using USB_USER and the built-in bootloader (activate with jumper between CN7.5 and CN7.7)

$ alias cubepgmcli='/opt/STMicroelectronics/STM32Cube/STM32CubeProgrammer/bin/STM32_Programmer_CLI'
STM32Cube_FW_WB_V1.4.0/Projects/STM32WB_Copro_Wireless_Binaries> cubepgmcli -c port=USB1 -fwdelete
STM32Cube_FW_WB_V1.4.0/Projects/STM32WB_Copro_Wireless_Binaries> cubepgmcli -c port=USB1 -fwupgrade stm32wb5x_FUS_fw.bin 0x080EC000 firstinstall=0
STM32Cube_FW_WB_V1.4.0/Projects/STM32WB_Copro_Wireless_Binaries> cubepgmcli -c port=USB1 -fwupgrade stm32wb5x_BLE_Stack_fw.bin 0x080CB000 firstinstall=1

Using ST-LINK (here to show the option bytes, SBRV : 0x32C00 means start address 4 * SBRV + 0x08000000 = 0x080CB000, 3D000 means there is no stack):

psi@homer:~/Dropbox/wbForth/CubeWB> cubepgmcli -c port=SWD -ob displ
      -------------------------------------------------------------------
                        STM32CubeProgrammer v2.3.0                  
      -------------------------------------------------------------------

ST-LINK SN  : 066BFF313335415043141250
ST-LINK FW  : V2J35M26
Voltage     : 3,21V
SWD freq    : 4000 KHz
Connect mode: Normal
Reset mode  : Software reset
Device ID   : 0x495
Device name : STM32WBxx
Flash size  : 1 MBytes
Device type : MCU
Device CPU  : Cortex-M0+/M4


UPLOADING OPTION BYTES DATA ...

  Bank          : 0x00
  Address       : 0x58004020
  Size          : 104 Bytes

[==================================================] 100% 


OPTION BYTES BANK: 0

   Read Out Protection:

     RDP          : 0xAA (Level 0, no protection) 

   BOR Level:

     BOR_LEV      : 0x0 (BOR Level 0 reset level threshold is around 1.7 V) 

   User Configuration:

     nBOOT0       : 0x1 (nBOOT0=1 Boot from main Flash) 
     nBOOT1       : 0x1 (Boot from code area if BOOT0=0 otherwise system Flash) 
     nSWBOOT0     : 0x1 (BOOT0 taken from PH3/BOOT0 pin) 
     SRAM2RST     : 0x0 (SRAM2 erased when a system reset occurs) 
     SRAM2PE      : 0x1 (SRAM2 parity check disable) 
     nRST_STOP    : 0x1 (No reset generated when entering the Stop mode) 
     nRST_STDBY   : 0x1 (No reset generated when entering the Standby mode) 
     nRSTSHDW     : 0x1 (No reset generated when entering the Shutdown mode) 
     WWDGSW       : 0x1 (Software window watchdog) 
     IWGDSTDBY    : 0x1 (Independent watchdog counter running in Standby mode) 
     IWDGSTOP     : 0x1 (Independent watchdog counter running in Stop mode) 
     IWDGSW       : 0x1 (Software independent watchdog) 
     IPCCDBA      : 0x0  (0x0) 

   Security Configuration Option bytes:

     ESE          : 0x1 (Security enabled) 
     SFSA         : 0xCB  (0xCB) 
     FSD          : 0x0 (System and Flash secure) 
     DDS          : 0x1 (CPU2 debug access disabled) 
     C2OPT        : 0x1 (SBRV will address Flash) 
     NBRSD        : 0x0 (SRAM2b is secure) 
     SNBRSA       : 0xF  (0xF) 
     BRSD         : 0x0 (SRAM2a is secure) 
     SBRSA        : 0xA  (0xA) 
     SBRV         : 0x32C00  (0x32C00)

   PCROP Protection:

     PCROP1A_STRT : 0x1FF  (0x8000FF8) 
     PCROP1A_END  : 0x0  (0x8000008) 
     PCROP_RDP    : 0x1 (PCROP zone is erased when RDP is decreased) 
     PCROP1B_STRT : 0x1FF  (0x8000FF8) 
     PCROP1B_END  : 0x0  (0x8000008) 

   Write Protection:

     WRP1A_STRT   : 0xFF  (0x807F800) 
     WRP1A_END    : 0x0  (0x8000000) 
     WRP1B_STRT   : 0xFF  (0x807F800) 
     WRP1B_END    : 0x0  (0x8000000)

21st Century Forth

http://www.forth.org/svfig/21st.html

What's good about Forth

small
easy to understand
extendable
adaptable to programmer
interactive
open compiler/interpreter
simple architecture
source code available
helpful in learning about hardware and software

What's bad about Forth

NIH (not invented here)
cryptic reverse polish notation
difficult to learn
documentation sometimes lacking or unavailable
unconventional syntax
no linkage with other languages
getting more complex
lack of data typing
source (proprietary protection problem)

What 21st Century Forth should be

work in embedded applications
work with networks and Internet
work with large systems (operating systems, graphic user interface)
be able to be taught to programmers and engineers

What Forth needs

reuseable binaries (other languages & headers)
more/better/useable libraries
safety (year 2000)
better documentation
more examples
workable standards
better gui/window editor w/more information
package confidence
more debugger integration
works with newer CPUs (embedded systems, MCU)
publications
big daddy $$$
educational opportunities
more types of multitasking/multiprocessing pre-emtive multitasking

21st Century Forth desires and vision

real/virtual machines/core
scriptmaking (language to taste)
real compile toggle (memory, speed, optimization)
integratable applications
"browser" environment *
environments (such as voice) interpretation (fuzzy)
pda's bases, smart cards, etc
servants (robots, etc) applications

Copyright

Authors

Matthias Koch - Forth on ARM Cortex M0/M4 - Mecrisp Stellaris
Peter Schmid - Initial work - Mecrisp-Cube

License

This project Mecrsip-Cube is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.

Mecrsip-Cube is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License along with Mecrsip-Cube. If not, see http://www.gnu.org/licenses/.

Acknowledgments

http://mecrisp.sourceforge.net/ Original Mecrisp project, Matthias Koch
https://mecrisp-stellaris-folkdoc.sourceforge.io/ Mecrisp Stellaris Unofficial UserDoc, Terry Porter
https://jeelabs.org/article/1612b/ Forth in 7 easy steps, Jean-Claude Wippler
https://forth-ev.de/ Forth-Gesellschaft e.V.
https://forth-ev.de/wiki/res/lib/exe/fetch.php/vd-archiv:4d2015-arm.pdf ARM-Sonderheft

-- Peter Schmid - 2019-12-29

Topic revision: r55 - 2020-04-07 - PeterSchmid