ActiveGPS firmware update process

 10.1.2025
ActiveGPS firmware update process

ActiveGPS MCU is PIC18F2455

&A   start op
&B   device info
&J    read EEPROM content

Read FLASH content
&E000000
&F
...
&F

Update firmware
&H0108
&G001 ... &G00B


Wireshark, export pcapng as plain text with data bytes

Frame 2178: 27 bytes on wire (216 bits), 27 bytes captured (216 bits) on interface \\.\USBPcap5, id 0

0000  1b 00 60 15 59 06 05 d4 ff ff 00 00 00 00 09 00   ..`.Y...........
0010  00 05 00 01 00 83 03 00 00 00 00                  ...........

Frame 2179: 565 bytes on wire (4520 bits), 565 bytes captured (4520 bits) on interface \\.\USBPcap5, id 0

0000  1b 00 a0 58 bc 09 05 d4 ff ff 00 00 00 00 09 00   ...X............
0010  00 05 00 01 00 03 03 1a 02 00 00 26 47 30 30 30   ...........&G000
0020  30 30 30 30 30

 

Some Python code to extract &G blocks

i = 0
s = ""
f = open('agps-ptext2.txt', 'r')
fo = open("fwdata.hex", "w")
lines = f.readlines()
l = len(lines)
while True:
    s = str(lines[i]).strip()
    if s.find('565 bytes on wire') > -1:
        i = i + 3
        for p in range(35):
            s = str(lines[i]).strip()
            s = s.replace('.', '')
            s = s.replace('&G', '')
            fo.write(s[56:])
            i = i + 1
    else:
        i = i + 1
    if i >= l:
        break
fo.close()
f.close()
print("c")