(minimal) TI MSP430 μC 1,2,4 Family BSL flasher (slau319af)

bsl124.py

"""
bsl124.py

(minimal) TI MSP430 1,2,4 Family BSL flasher
using pyserial, works on windows, mac, and linux

 - implementation of slau319af.pdf
 - programming MSP430 chips via USB-TTL / FTDI / ...
 - supports Intel HEX format
 - supports F1xx, F2xx, F4xx, G2xx3 chips

usage:
  python3 bsl124.py -p /dev/cu.usbserial-110 -i blink.hex

hardware connection example:
             ____3V3______        5V              3V3
            |             |        |  +---------+  |
        +-------+   +-----------+  +--|VI GND VO|--+
+---+   |  VCC  |   |    VCC    |  |  +---------+  |
| 5V|   |     TX|---|BSLRX(P1.5)|  =10uF   |       =10uF
| D+|---|D+   RX|---|BSLTX(P1.1)|  |______GND______|
| D-|---|D-  DTR|---|RST        |   
|GND|   |    RTS|---|TEST       |   RST--[10Kohm]->3V3
+---+   |  GND  |   |    GND    |   TEST-[10Kohm]->GND
 USB    +-------+   +-----------+   3V3--[100nF ]->GND
          CH340C     MSP430G2553    3V3--[100nF ]->GND

 - I use CH340C but you should be able to use any
   USB to serial/UART/TTL/RS-232 chips
 - FTDI cables often don't have DTR line (only CTS/RTS),
   so you might need a breakout board / custom PCB
 - check the datasheet of your chip for assignment
   of the BSL TX/RX pins, they're different from TXD/RXD

example hex file for G2553, for your testing convenience:

:10C00000314000040C43B0120AC02183B240805A70
:10C010002001F2432200F2432A005C4221007CE32B
:10C020003CF0FF00C24C21005C4229007CE33CF064
:10C03000FF00C24C2900B140102700002C413C53A6
:0CC04000814C00002C410C93F923E73FD9
:02FFFE0000C041
:040000030000C00039
:00000001FF

- this code blinks all the pins on PORT1 and PORT2,
  connect an LED to any.
- you can use msp430-elf-gcc and msp430-elf-objcopy
  (available from TI's website) to make hex files.

example output from bsl124.py:

====== parsing ihex file  ======
block sizes: [16, 16, 16, 16, 12, 2]
===== opening serial port  =====
/dev/cu.usbserial-110
== sending BSL init sequence  ==
========== mass erase ==========
SYNC ACK. CMD ACK.
=== sending default password ===
SYNC ACK. CMD ACK.
====== sending RX blocks  ======
1 / 6 ... SYNC ACK. CMD ACK.
2 / 6 ... SYNC ACK. CMD ACK.
3 / 6 ... SYNC ACK. CMD ACK.
4 / 6 ... SYNC ACK. CMD ACK.
5 / 6 ... SYNC ACK. CMD ACK.
6 / 6 ... SYNC ACK. CMD ACK.
=== loading program counter  ===
SYNC ACK. CMD ACK.
DONE.

(c) lingdong 2023, MIT License
"""

import serial # pyserial.readthedocs.io
import time
import sys

DTRRTS_NOT_INV = 0
ARGS = {
  '-p':"/dev/cu.usbserial-110"
}

frame_state = -1
ser = None
ckl = 0
ckh = 0

for i in range(1,len(sys.argv),2):
  try:
    k = sys.argv[i];
    if k == "--help" or k == '-h':
      print("usage:\n\tpython3 bsl124.py -p [port] -i [file.hex]")
      exit(0);
    v = sys.argv[i+1];
    ARGS[k] = v
  except Exception as e:
    print("ERR: bad arg:", k)
    exit(1)

def parse_ihex(filepath):
  lines = [x.strip().split(':')[1] for x in open(filepath,'r').read().replace("\r","\n").split('\n') if len(x.strip())];
  recs = []
  for l in lines:
    typ = int(l[6:8],16)
    num = int(l[0:2],16)
    if (num > 250):
      print("ERR: ihex record too long (250 max.): ",l)
      exit(1);
    if (num & 1):
      print("ERR: ihex record length not even: ",l)
      exit(1);
    if (typ == 0):
      recs.append({
        'bcnt': num,
        'addr': int(l[2:6],16),
        'data': [int(l[i:i+2],16) for i in range(8,len(l)-2,2)]
      })
  return recs


def serial_open():
  global ser
  ser = serial.Serial(
    port=ARGS['-p'],
    baudrate=9600,
    bytesize=serial.EIGHTBITS,
    parity=serial.PARITY_EVEN,
    stopbits=serial.STOPBITS_ONE,
    #rtscts=True,
    #dsrdtr=True,
    timeout=2,
  )
  print(ser.name)


def set_dtr(v):
  ser.dtr = not (v ^ DTRRTS_NOT_INV)
  time.sleep(0.05)

def set_rts(v):
  ser.rts = not (v ^ DTRRTS_NOT_INV)
  time.sleep(0.05)

def send_sync():
  send_byte(0x80);
  ret = read_byte()
  if (ret == 0x90):
    print("SYNC ACK.",end=' ',flush=True)
  else:
    print("SYNC NOT ACK:",ret);
    exit(1);

def init_seq():
  set_dtr(0)
  set_rts(0)
  time.sleep(0.1);
  set_rts(1);
  set_rts(0);
  set_rts(1);
  set_rts(0);
  set_rts(1);
  set_dtr(1);
  set_rts(0);
  time.sleep(0.2);

def send_byte(b):
  global frame_state, ckl, ckh
  ser.write(bytes([b]))
  if frame_state != -1:
    if frame_state:
      ckh ^= b
    else:
      ckl ^= b
    frame_state ^= 1


def read_byte():
  return int.from_bytes(ser.read(1),'little');

def start_frame():
  global frame_state, ckl, ckh
  send_sync();
  ckl = 0
  ckh = 0
  frame_state = 0

def end_frame():
  global frame_state, ckl, ckh
  frame_state = -1
  send_byte(ckl^0xff)
  send_byte(ckh^0xff)
  ret = read_byte()
  if (ret == 0x90):
    print("CMD ACK.")
    time.sleep(0.2)
  else:
    print("CMD NOT ACK:",ret);
    exit(1);

def cmd_load_pc():
  start_frame();
  send_byte(0x80);
  send_byte(0x1A);
  send_byte(0x04);
  send_byte(0x04);
  send_byte(0xFE);
  send_byte(0xFF);
  send_byte(0xFF);
  send_byte(0xFF);
  end_frame();


def cmd_rx_password0():
  start_frame();
  send_byte(0x80);
  send_byte(0x10);
  send_byte(0x24);
  send_byte(0x24);
  send_byte(0xFF);
  send_byte(0xFF);
  send_byte(0xFF);
  send_byte(0xFF);
  for i in range(0,0x20):
    send_byte(0xFF);

  end_frame();

def cmd_mass_erase():
  start_frame();
  send_byte(0x80);
  send_byte(0x18);
  send_byte(0x04);
  send_byte(0x04);
  send_byte(0xFF);
  send_byte(0xFF);
  send_byte(0x06);
  send_byte(0xA5);
  end_frame();

def cmd_rx_data(rec):
  # print(rec);
  start_frame();
  send_byte(0x80);
  send_byte(0x12);
  l1l2 = rec['bcnt']+4;
  send_byte(l1l2);
  send_byte(l1l2);
  send_byte(rec['addr']&0xFF);
  send_byte((rec['addr']>>8)&0xFF);
  send_byte(rec['bcnt']);
  send_byte(0);
  for i in range(rec['bcnt']):
    send_byte(rec['data'][i])
  end_frame();

print("====== parsing ihex file  ======");
recs = parse_ihex(ARGS['-i'])
print("block sizes:", [x['bcnt'] for x in recs])
print("===== opening serial port  =====");
serial_open();
print("== sending BSL init sequence  ==");
init_seq();
print("========== mass erase ==========");
cmd_mass_erase();
print("=== sending default password ===");
cmd_rx_password0();
print("====== sending RX blocks  ======");
for i in range(len(recs)):
  print(i+1,'/',len(recs),'...',end=' ',flush=True);
  cmd_rx_data(recs[i]);

print("=== loading program counter  ===");
cmd_load_pc();
print("DONE.")