I've designed a board based on the pmu tps65910 and the processor AM3703. The pmu generates the correct switching sequence for the supply rails and the correct clock of 32kHz.
The main clock of the processor is comming from a oscillator with 26 MHz. This clock can be measured on sys_clkout1. The sys_boot[6:0] pins are arranged so that the clock is comming from oscillator (sys_boot_6=HIGH), booting order is memory (sys_boot_5=LOW) and the first boot should be the MMC1 (sys_boot_4=HIGH, sys_boot_3=LOW, sys_boot_2=HIGH, sys_boot_1=HIGH, sys_boot_0=LOW).
To test the boot process i have not inserted the Memory card and i have expected to see on UART3 the ASIC-ID request, on startup.
Because the request was not seen, i suppose that the internal ROM code preinitializiation step (configuration of clocks and DPLL) can not be executed.
I've checked the PLL supply voltage, the states of the reset pins and everything is ok but the processor can not boot. At the moment i have no frther ideas how to solve the problem.
Any informations are welcome.
P.S.: Due to our layout we have no possibility to measure the output clock on pin sys_clkout2.
Best regards,
Alexandru Mixich