??? 05/05/05 03:58 Read: times |
#92959 - Problem using 89C51RD2BN |
Hi,
I have been using the 89C51 microcontroller for quite some years. When I started using the 89C51RD2BN from phillips, it didn't work initially. Then I grounded the PSEN pin as I was using the internal code memory only, then it started working and I did not face any problem. Recently, the newer lot of 89C51RD2BN did not work. I tried to procure these from different sources, but the controller doesn't seem to work. I am able to burn and verify the internal flash(using parallel programmer), the chip seem to work properly if an external eprom is used, but it does not work using the internal flash. I am using 11.0592MHz crystal. I have tried burning the chip at both 6 and 12 clock. My same board works fine with the earlier lots of 89C51RD2BN. What can be the possible problem. Mohit |
Topic | Author | Date |
Problem using 89C51RD2BN | 01/01/70 00:00 | |
Some hints... | 01/01/70 00:00 | |
could be the famous open pin | 01/01/70 00:00 | |
EA is tied to VCC | 01/01/70 00:00 | |
are they H? | 01/01/70 00:00 | |
without 'H' | 01/01/70 00:00 | |
AN-461 | 01/01/70 00:00 | |
I am using a parallel programmer | 01/01/70 00:00 | |
can the chip go into ISP mode directly | 01/01/70 00:00 | |
clear and do not fiddle | 01/01/70 00:00 | |
Thanks, it worked![]() | 01/01/70 00:00 |