Unable to connect P89V51RD2 through ISP

Started by sanketbarot, November 27, 2007, 07:46:40 PM

Previous topic - Next topic

sanketbarot

When first time I programmed the p89v51RD2 i had chcked the security bit.
Now to again program this chip i need a parallel programmer.
so i used the parallel programmer and the program the chip and this time i had not check the security bit.

But once i programmed through a parallel programmer i am not able to connect the chip through ISP. I always need a Parallel programmer.

So now how I can connect through ISP??

Andy Ayre

Did you erase the entire device using the parallel programmer? If so then you probably erased the bootloader. You can download a new copy from the resources page of this site and program it back in using the parallel programmer.

Andy
Embedded Systems Academy, Inc.
support at esacademy dot com

Je Gold

Some Universal Parallel programmers have very poor wording to describe the flash erase operation of the P89v51.

There are 2 flash blocks - block 0 (user code)    block 1 (bootloader code)

Some programmers will erase block  1 - without telling you.......  If this happens then you need to reprogram block 1 with the bootloader code and bllock 0 for your user code...... otherwise the P89v51 will be stuck in block1 and will never execute block 0 user code.


The bootloader code is available from the NXP web site under the production information page of the P89v51.


Regards
Joseph