How to reverse engineer an bluetooth HCI log to add a new Printer ?

[anthony-foulfoin]

Hi,

I have a Peripage A40+ printer 304 dpi. I wanted to make a PR to add its support, but even with all the bluetooth logs and analysing in wireshark I don't know where to find the necessary informations.
I looked at the commit that added the A40 https://github.com/bitrate16/peripage-python/pull/11/commits/90683dcd3ffb53c42639473c81036fe4463e82ed but it doesn't help me to know what to search for in the logs. Where do you find all those informations ?

Thanks !

[bitrate16]

Try this code:

import peripage

printer = peripage.Printer(
    # MAC
    mac='00:15:83:15:BC:5F',
    # Doesn't matter:
    printer_type=peripage.PrinterType.A6p
)
printer.connect()

# Print many letters in hex to determine the width
printer.writeASCII('0123456789ABCDEF' * 20)

printer.disconnect()

This shoud print 0123456789ABCDEF repeated 20 times. Count length of line in 16base, convert to 10base and you will get the width of line in characters.

Next, add your printer spec here:
https://github.com/bitrate16/peripage-python/blob/main/peripage/__init__.py#L46
similar to others, or tell me and i'll add:

row_characters=SOME_VALUE_YOU_GOT
row_width=row_characters * 12
row_bytes=row_width // 8