Hello, I am trying to understand the GL640USB IEEE-1284 to USB Bridge. I have looked at a few implementations of this bridge. Each time the following registers are used (this code is from the canon630u backend):
/* Register codes for the bridge. These are NOT the registers for the scanner chip on the other side of the bridge. */ typedef enum { GL640_BULK_SETUP = 0x82, GL640_EPP_ADDR = 0x83, GL640_EPP_DATA_READ = 0x84, GL640_EPP_DATA_WRITE = 0x85, GL640_SPP_STATUS = 0x86, GL640_SPP_CONTROL = 0x87, GL640_SPP_DATA = 0x88, GL640_GPIO_OE = 0x89, GL640_GPIO_READ = 0x8a, GL640_GPIO_WRITE = 0x8b } GL640_Request; However, I have gone through the official datasheet supplied by Genesys and could not find any documentation on these register addresses. In fact, according to page 10 in the datasheet, the registers on the above addresses have different meanings. What am I missing here?? Thanks, Robert