Hello,

I have connected an AD7718 and P89C51RB2 microcontroller with minimum lines has shown in the Analog Devices data book for AD7718, ie I have shorted Din and Dout lines of the AD7718 pulled up with 10K resistor and tied to one port pin of P89C51RB2, the Sclk line of the AD7718 also goes to one port pin of the P89C51RB2, I am not able to write or read the device.

In this configuration, Analog Devices recommends resetting the devices by reading the device for 24 clock cycles and then writing a 1 to the device for 32 clock cycles.

My question is how will the device know whether it is being read or written, when the Din and Dout pins are tied together?

I will be thankfull, if some one can throw some light on the above.

Regards,
John.