Hi Nicholas,
On 08.07.20 01:38, Nicholas Williams wrote:
I am wondering if anyone has a copy of the PPC440EPx evaluation board (Sequoia) schematic that was made by AMCC. The information is no longer easily available as the amcc.com and apm.com sites are no longer running and the schematic is not archived on the wayback machine. I figured that U-Boot might be a place to ask for this schematic but if this is not an appropriate topic I apologize.
I am currently tasked with testing a PPC440EPx-NUA667T for a customer. One part of the testing will require me to boot the processor up to confirm it functions. I cannot use an evaluation board to do this testing because each processor I am testing cannot be soldered onto a board. The testing is being done with a socket on a test fixture which is interfaced with a high speed digital testing system. Due to this setup I have to input individual test vectors to the processor which is much at a lower level then the type of code that I have found on places like U-Boot. I am having trouble writing instructions to the device once it comes out of reset so I wanted to see the evaluation board schematic to understand how the PPC440EPx was interfaced to its boot rom. I can successfully get the device to come out of Reset (de-assert ExtReset) and the EBC is putting out addresses to the PerAddr pins (27-31) as I have configured the bootstrap pins to use condition C from the PP440EPx User Manual (EBC boot with a 16 bit boot width). However I have not had any luck putting in instructions during this phase. I believe I am incorrectly putting instructions into the PerData pins as the device does not respond to any commands.
If anyone can help I can provide screenshots of the waveforms I get from the device else the PPC440EPx evaluation board schematic might shed more light on how to properly communicate with the EBC.
Unfortunately my PPC4xx memories have faded, since I last worked on these SoC's many years ago. I've attached the schematics and the user manual for Sequoia. HTH.
Thanks, Stefan