Project:RELaserSoftware/USB protocol

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Revision as of 20:07, 8 July 2011 by Wonko (talk | contribs) (Added basic command format)

Vendor: 0548 Product: 1005

The protocol seems to be fairly simple. I have a capture of some file downloads and deleting a file.

looks like:

commands are sent to endpoint 0x04 and read form 0x88, sent commands are (byte)length and then length bytes

commands 5 and 6 seem to be start and end

example command block:

>w04 0002     00000000: 01 05
*r88 0001     00000000: 04
>w04 0006     00000000: 05 01 01 83 01 7a
*r88 0001     00000000: 06
*r88 0001     00000000: 05
>w04 0002     00000000: 01 04
*r88 0014     00000000: 0f 01 83 53 51 55 41 52 45 20 20 4d 4f 4c 00 0e
    00000010: 00 00 00 66
>w04 0002     00000000: 01 06

That last reply packet includes the ascii for 'SQUARE MOL' with two spaces in the middle to pad it to 11 characters. This must be a file name in DOS 8.3 format with the . implied between the 8th and 9th characters.

This presumably maps directly to a FAT16 entry, so don't let it be null or begin with a dot!

It isn't, the protocol dosn't seem to be doing any block level management at all, looks like the controller is nice enough to do that for us JasperWallace 01:11, 28 November 2010 (UTC)

All USB command follow the same format:

host  01 05:  sending 1 byte: are you there?
laser 04: yes I am here
host  05 01 01 10 06 e8: sending 5 bytes, 1 byte payload, always 1, 10 is the command, 06 is the payload, e8 is the checksum
laser 06: OK, I received and understood (ACK)
laser 05: host, are you there?
host  01 04: sending 1 byte, yes i am here
laser 00 01 10 00 ef: 0 bytes payload, always 1, repeating the command sent, payload would be here, 00 is OK (81 is checksum error), checksum
host  01 06: sending 1 byte, OK (ACK)