Problem in programming Flash of P89C668

[Inder]

Hi,
I am trying program flash of P89C668, but I am not able to connect to the device. Also, I am not able to read, erase, read device signature etc. because of problem in connection. I am using crystal of 11.0592 MHz. Is there any setting required to be done for this frequency. Also I tried with some already programmed chip. In that the program sends some data to the serial port. But, I am not receiving it in Hyper terminal. Could somebody please help me out?? Waiting for reply.

Thanks and Regards,
Inder.

[Andy Ayre]

Try 9600 baud.
Verify with a scope on the PSEN and Reset pins of the device that you are meeting the requirements in the datasheet to place it into ISP mode.
Also for this ancient device you need to pull P2.6 and P2.7 high during reset to place the device into ISP mode.

Also talk to Sumant in your company - he has managed to get Flash Magic to communicate with an 89C668.

Andy

[erikm]

I  believe that the '668 just like the original Rx2 need P1.6 and p1.7 kept high.

Erik

[Andy Ayre]

I believe it is P2.6 and P2.7.

Andy