I am experiencing difficulties in controlling a AD9959 on the evalboard with a microcontroller and would be extremely glad for any hint to the problem.
I am using the AD9959/PCBZ REV.C. Voltage supply is given and it operates flawlessly with the delivered software.
For testing purposes I would like to set the ref clock multiplier from 0 to 4, as this seemed to me to be a short and simple command. I am supplying the ref clock into J9 and observe the multiplied clock on a scope on J13/Sync clk. Jumper settings are: W10, W9, W4/5/6 set and W11 set to external clock, W7 set to PC, the rest are open.
Next I grabbed the signals as produced by the onboard controller when changing the multiplier from disable to 4 in the evaluation software.
Here the channels are:
4->Chip select, CSB (wrongly labled MISO in the annexed picture)
I pull SDIO_1, SDIO_2, SDIO_3 and PWR_DWN to ground, the rest are left open.
With the recorded signals the change of the multiplier via usb works flawless.
Now to connect the microcontroller, I remove W10, connect CS, MOSI, SCLK, UD_CLK and MST_RST to the controller and switch jumper W7 to manual.
The other annexed images (the ones ending in BBB) show the signals I generate with the microcontroller with the same connection to the scope as before, MST_RST is kept at logic low the whole time, or issued once for 1ms, both without any effect.
The transmitted words are:
in both cases.
If I try to set the multiplier with the evaluation software, but without auto update, change the connections to the microcontroller and trigger the update with the controller, everything works fine. Also issuing a MST_RST with the µC works. But no matter what I tried the transmitted data won't be recognized.
I appreciate any commet or hint to the concealed problem,
PS. there are only 5 annexed items permitted. The last picture that is missing just looks like the others very much alike the USB version.