CFA-635 Return data with VB6


New member
I have just got a CFA-635 Rs232... what a cool device! Ok I have got it runing fine with the supplied software and cabn send a retrive data fine.. So I need to write something in VB6.... I can now send data TO the device... set characters... turn the brighness up and down.. etc... BUT I get garbage replies and NO data returned when buttons are pressed.... am i missing something obvious?
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CF Tech

The module should return a packet as documented in the data sheet.

A key report will return as follows:

There should be the 0x80, the length of 0x01, then one of the 12 key codes, then the two bytes of CRC. Each key transition should result in two packets being returned, one with a "press" code, and one with a "release" code.

Ideally, your code should parse the packets and verify the CRC, but checking for a 0x80, and the 0x01 followed by a byte between 1 and 12 should get you pretty close.
USB LCD Displays - Graphic and Character LCDs with a Keypad