HP Compaq G750 USB Conversion

Question

Hello, I need help working out how to convert the HP Compaq G750 to USB using an Arduino pro micro. So far I have worked out that it uses RS232 so hooked it up using a MAX232EPE to the Arduino and loading the attached sketch onto it. I now get feedback over serial but I don't understand how to parse it as I can't find any info on this online and don't have any more advanced tools like an oscilloscope to make sure I'm using the correct baud rate. I have attached some data I have pulled with various actions. If needed I can provide a fritzing sketch with my wiring layout but it is based on https://imgur.com/vxgZs without the 10uF capacitor or that trace. I have also attached a few pictures of the inside of the connector and its wiring. (I hooked it up with 3.3v) Any help would be appreciated, Thanks. 
 Attachments: iPAQ_Keyboard.ino.txt.zip Keyboard data.txt.zip

shabaz · Answer

You have a variable length of bits, sometimes 21 bits, and sometimes 23 bits and sometimes 24 bits.

I can't see a pattern, but was just wondering, why not pattern match on all these bits, it wouldn't take a lot of flash memory.

You'd need to compare the input bits with all the patterns stored in memory, until you find one that matches, or (easier) that has the longest match.

It is not ideal, but in theory I can't see why that wouldn't work.

HP Compaq G750 USB Conversion

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