Dear all,
I'm working with UCD90SEQ48EVM-560 evaluation kit (and UCD9090 device on socket), and I'm testing it with our ISP programmer for which I've already developed a complete programming software on UCD30xx devices. According to TI experts, Boot ROM interface for UCD30xx devices should work also for UCD9090.
I tested this environment with Fusion Digital Power software via USB interface and I verified this device is in erased and in Boot ROM state. I also programmed it several times without any problem.
I connected this environment to my ISP programmer using PMBUS_CLK and PMBUS_DATA pins, powering with 5V power supply (J5 connector).
The result is that communication is "unstable": same commands repeated several times sometimes pass, sometimes fail. If communication frame is "long" (for example reading all the memory to check if the device is blank) results with a sure failure. This never happens with Fusion Digital Power.
1) I checked WDI and WDO pin to verify if some Watchdog is active, seems not.
2) I tried several communication frequency from 50kHz up to 4000kHz without luck
3) I assumed (as I never found in device datasheet) that flash memory is mapped as UCD3020 starting from address 0x10000. Flash size is still unknown to me. Could you please give me this information?
4) I checked signals behavior with oscilloscope: I2C has 9-bit-packet: bit 9 is dedicated to ack. In my case, packet that generate the failure means that device answer with NACK (bit 9 = HIGH). Repeating this packet produce always the same result.
5) Signal quality is high, no noise and good rise/fall edge.
Please give me some suggestion, unfortunately I could not sold a board only with the DUT on because they have QFN package and are difficult to manage by hand.
Thank you for your kind help.
Regards,
Samuele Stefanoni
