Need some help with the AT89C51ED2

[daniel_pt]

I used to work at lot with these microcontrollers when I was at the Uni and as I had one here with me, I thought of putting it to work and spending some time making some gadgets...

I got the circuit all together but I'm having this problem:

When trying to program the ED2 with Flip, I can connect, erase and do the blank check with no problems, but I can't program as I always get the Timeout Error message... :|

I already tried the FLIP 3.3.1 and 2.4.6 always with the same results. Tried with AutoISP enable and disable and still no blinking leds!!

What might be the problem? can the micro be damaged!? something I am doing wrong?

Thanks to any helper!

cheers

 

[ckshivaram]

Which programmer are you using to program the IC

 

[ctownsend]

I got the circuit all together but I'm having this problem:
cheers

what circuit? Are you trying to program the ED2 on your board, or is it a separate circuit?

When trying to program the ED2 with Flip, I can connect, erase and do the blank check with no problems, but I can't program as I always get the Timeout Error message... :
cheers

if the circuit is okay, try lowering the baud rate in flip. I also found that FLIP works best when you have a 11.0592 MHz clock.

I have also noticed that flip 2.46 does not support older ED2's. (the ones with bootloader version 1.0)

I had to downgrade to Flip 2.4.4. Never had a problem with it. Have a look at the circuit I uploaded.

Good Luck

 

[daniel_pt]

Thanks for the replies! Some hours later, I could perform every action with FLIP. The problem was in the baud rate. I can only work at 38400bps. lower or higher than this, I can't program the microcontroller... it's odd and I don't know why it happens.

The circuit I use is exactly the same but with a 20MHz xtal...