Hello,
I've been trying to work with the PEF7071, I tried some firmware in the Cyclone 10 LP Evaluation board and everything works correctly, but when implementing the same firmware to our custom board we're having problems to make it work.
This is the schematic of our board:
NOTE IMPORTANT!!: This schematic is and old revision, the actual PCB has two important changes. Pin 43 is now connected to ENET_SCL, pin 44 is now connected to ENET_SDA. We have added a capacitor between GND_E and resistors R102, R103, R104 & R105. These are not mistakes anymore.
We've checked all the voltages of the board and everything seems alright, we have 2.5V at the chip and 1V generated from the circuit coming from REGO.
The MDIO is working (we're using and FPGA to talk with the chip) and we've checked the registers, I don't have the results, but if required I can send all the register values next week, for now I only have these ones (all of them except for the extended ones):
We've been comparing the behaviour of the chip with the one of your evaluation board and we've found some weird stuff around the transformer/RJ-45/TPI signals. When doing a reset we first see this (these are the TDI Differential signals A, B, C & D):
The signal gets stuck there, but at random moments we see an increase in consumption and the see something like this:
But it doesn't last more than 1s, when looking at the Cyclone 10 we also see the first picture after reset but shortly after we start receiving signals like in picture 2. I don't know if this can help solve the problem.
Thank you for your time,
Gerard
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Hello Gerard,
We have problems on a PEF7071 design too.
In your case there maybe a wrong interconnection of transformer and jack pins. Your connection:
Pair A is correctly connected to pins 1 & 2
Pair B should be connected to pins 3 & 6
Pair C should be connected to pins 4 & 5
Pair D is correctly connected to pins 7 & 8
Hope that helps.
Sergio
