FX3 Bulk in Endpoint bad data for first 1K of transfer | Cypress Semiconductor
FX3 Bulk in Endpoint bad data for first 1K of transfer
I have a FX3 super speed explorer board connected to a Xilinx KC705 FPGA development board. I am wanting to bulk read data in from the KC705 FPGA and created a GPIF project to do that based on John Hydes GPIF Example8 project (from his book SuperSpeed Device Design by Example). The problem I have is the first 1K bytes (or whatever my DMA buffer size is set to) are all 0
when the Transfer Data In command is issued in the USB Control Center. The data I am expecting and I have verified with a logic analyzer is not seen in the USB Control Center panel until 1024 + 12 Bytes (when I use a 1K buffer size) down in the display.
I have attached the frimware files for this project. I am puzzled as to why the data I am expecting is not seen until 1 buffer (1K) down in the data display.