Hello dear e2e-community,
we are having problems with the EPI-interface on the Concerto F28M35H52C1 Chip. We are using the Control Card (rev. 2) for developing and prototyping purposes which comes with the Rev. B of the chip.
At the moment, our main problem is that the controller pins, which have to be used for EPI, are not on the control card interface. In the pcb layout of the Concerto F28M35 Control Card, not all of the corresponding Pins are routed on to the DIMM100 connector, and therefore you cannot use it for prototyping.
We checked for different modes of EPI (different address/data bus sizes), but for no combination from the datasheet do we reach a full pin out configuration. There are examples for interfacing some memory chips in the control suite, but: how can one test this, when the pins are not available? Most other interfaces (e.g. SPI, I2C) have multiple Pin alternatives which can be configured in software with the GPIO MUX, but for EPI there seems to be only one Pin for every EPI signal. Do we have to create our own pcb layout to use EPI?
Or this there some trick, or can we configure the pins in some other way? How do other people prototype their EPI with the control card?
Our goal is to interface the Concerto Chip to an FPGA via high speed parallel bus - the EPI seemed to be ideal for this, but now we are a little disappointed and try to do this parallel bus in software ... We are very flexible on which GPIO Pins to use, and we only need 8 data bits, and if possible 4 address bits, additionally of course read, write and clock signal. But there seems to be no possible EPI-pin configuration on the control card. We are already thinking of soldering small wires directly on the processor pins.
I would greatly appreciate your help, and thanks in advance,
Philipp
