We met a problem during our test of FMC 230 board. The probem is as follows: We can't write or read any registers on FMC230 board through SPI interface. For example: We try to read the register of 0x2 address in CPLD Register map, we get all zeros always. It looks that SPI slave such as CPLD doens't respond correctly. And we continue to check more on FMC230 board, it seems that the chip ADG3304 on FMC230 doesn't work well. Our setting of ADG3304 is as: 1) the pin of VCCA and EN is connected to 2.5V 2) the pin of VCCY is connected to 3.3V
We try to access SPI interface from A side according to Figure 11 in FMC230 user manual, A1: chip select, active low A2: Clock A4: SDI/SDO interface
And we check the signal at these 3pins, it is fine. And we check signals on Y1, Y2, Y4, it should be of 3.3V level of signals, but there is wrong signals here. Y1: the CS's output is lower than 2.5V Y2: the clock's output is lower than 1V, and it is shifted by 1V or so. Y4: the output voltage is about 1.5 or even lower.
We don't know why these problems happen? Is CPLD correctly programmed for tri-state control? Or you can send new CPLD program used on FMC230 board to us to update. Wish for urgent support from 4DSP team.
This topic is being closed because the issue is considered as resolved by 4DSP. Feel free to create a new topic for any further inquiries.
over 4 years ago
Dear 4DSP support team,
According to ADG3304 user manual, it needs at least 20mA current, but our mother board is Xilinx K7 series FPGA, with 2.5V IO voltage, its maximum output current is less than 16mA, I worried about whether this maximum 16mA current is not enough to drive ADG3304, could you help to verify it for me? If it is so, how can your FMC230 use with such Xilinx series FPGA?