Hello folks,

I am using an AD7718 evaluation board and a Rigel RITA51J 8051 based evaluation board for a project.

I have wired up the two boards just as page 35 in the Analog Devices data sheet with one exception - I am using P3.4 (for din/dout) and P3.5 (sclk) rather than P3.0 and P3.1

RESET is wired high to DVdd, CS is wired low to Dgnd and DIN/DOUT are wired to a 10 kohm pull-up resistor, then to DVdd.

DIN/DOUT to P3.4
SCLK to P3.5

When I just test the code on the board without P3.4 connected I can see pulses coming out of P3.4, but when I connect P3.4 it to the AD board, its held low. I have tested with a simple led and with an oscilloscope. P3.5 works fine connected or disconnected.

I have linked the grounds of both boards.

Any pointers for this hapless, confused student? (Such as "maybe should try gardening?") Is there something on the wiring diagram I have missed, or something else I need to do with the 8051?

Rgds,
Eoin