ADE7753 Evaluation Board SPI interface

Hi,

I am from India. For a pilot project for an energy company I was asked to test out the ADE7753 evaluation board with a MCU. The "ADE7753/6/9 EVAL BD Z" was bought/imported online from Digikey.com. The board was received in tip-top condition.

Setup:

Since we are not interested in any of the installed software in the CD but actually to interface with a MCU for a smart metering pilot, what I did was I cut the parallel cable, isolated the wires and soldered them onto cables that can run into a Raspberry PI (presently its a RPi but I guess it can be any MCU for that matter). The PIN configurations were taken out of the DS page 13. They were done as follows:

Parrallel port pin | Function
        3                       RESET
        2                       DIN (MOSI)
        13                     DOUT(MISO)
        5                       SCLK
        4                       CS
        10                     IRQ
        11                    SAG
        12                    ZX
        15                    CF
        18                    GND

5V DC is provided for both the DVDD (SK4) and Vin(SK5) for the Optical isolator side. We have not yet used any Load Voltage or Current yet. We want to first try out the default values first as specified below so as to establish that the communication is working fine.

I wrote the "device driver" for the ADE7753 in C on Linux (R-Pi). I have done dozens of SPI programming stuff using the Rasperry bcm2835 libraries so I am completely familiar with SPI communication. I meticulously followed the instructions of communicating with the Serial Interface on ADE7753 from the ADE7753 DS exactly. I found it quite simple and straight forward to be honest - on the falling edge of CS when the ADE7753 goes in to the comm mode, write to the comm register indicating Read or Write and then the actual data transfer. That is exactly what I am doing. I am not using the IRQ, SAG, ZX, CF as yet now as they are output pins and I have left them dangling. I am using only parallel port pin 18 as GND for the opto coupler.

The ADE7753 DS Table 12 summary of registers show many registers that should give non-zero default values eg. PHCAL, IRQEN or even the most obvious DIEREV. But the trouble is I am getting a 0x0 output for all reads including DIEREV. That's not correct, right? If I close the jumper JP14 to connect the optical isolator GND to the DGND, then all I get is 0xFF for every read including DIEREV.

Please help us fix this problem. What could we be doing wrong?

Thanks

DJ Baruah