P89C51RD2 ISP problems

[erikm]

1) anything but a supervisor chip is asking for it.
It only can be reprogram if i erase and blank the chip again
FlashMagic automatically does this, what are you doing?

It all sounds like loss bootvector, which can only be restored by parallel programming.

Next time install NoTouch (and, if developing, "the backdoor") and live happily ever after.

Erik

[Arch Yap]

1)  It only can be reprogram if i erase and blank the chip again
FlashMagic automatically does this, what are you doing?  

I mean i restored by a parallel programming

2)Next time install NoTouch (and, if developing, "the backdoor") and live happily ever after.

I read the Back door article, does it mean the start Go to Boot is activated by helding one of the pin low and jump into the loop that actual write status byte, boot vector and wait for the watchdog to reset it.

I didn't implement watchdog circuit, it's only the RC circuit, how do i proceed with my current design.  and Why is the MCU did 't jump to ISP even  i held the /PSEN low and p.2.6 7 P2.7 high, ALE high.  ?? Anyother ways to solve my problesm since my circuit is designed utilising the RC circuit.

Thanks for your information

[erikm]

I read the Back door article, does it mean the start Go to Boot is activated by helding one of the pin low and jump into the loop that actual write status byte, boot vector and wait for the watchdog to reset it.

Yes,

I didn't implement watchdog circuit, it's only the RC circuit, how do i proceed with my current design. and Why is the MCU did 't jump to ISP even i held the /PSEN low and p.2.6 7 P2.7 high, ALE high. ?? Anyother ways to solve my problesm since my circuit is designed utilising the RC circuit.

Do NOT confuse a supervisor with a watchdog.  The fact that some suprevisors also function as a watchdog is irrelevant for this purpose.  I would recommend using a tripod supervisor and the internal watchdog.


You can't.  If you read the errata it states (in polite words) "if you use RC reset you are screwed".

Erik

[Arch Yap]

HI Erik,

Thanks for your information, i've succeffully put the chip in ISP mode thru the "back door' as suggested by you guys !!

Thanks !!

[erikm]

I read the Back door article, does it mean the start Go to Boot is activated by helding one of the pin low and jump into the loop that actual write status byte, boot vector and wait for the watchdog to reset it.



Yes,

Erik

[Manjeet Singh]

Help Please...

after getting frustrated from 89S8252 I switched to P89C51RD2. On the first shot I was able to progam the blank chip using Flash Magic.

But now when every I tried to reprogram chip again every time it says "unable to connect at specified baud rate try reducing the baud rate.

I read the AN461 article. I pulled the PSEN LOW on reset but the chip doesnt run in the Bootcode but insted it always runs the user code starting at 0000H

Pleae help

regards.........Manjeet

[erikm]

get rid of the RC reset, then restore the chip in a parallel programmer.

Erik

[erikm]

dorry - incomplete, should be

get rid of the RC reset, add a supervisor, then restore the chip in a parallel programmer.

Erik

[lechevelu]

Hi,

I'm trying to program my P89C51RD2HBP and i have every time the message "unable to read the security bit ...". I have the same message when nothing is connected. I think my rs232 line is god and my max232 ok too. Ready the data sheet of the micro controller, i have read that 2.6 and 2.7 must be "1". How can i do that ??

Thanks in advance for your help !

[Andy Ayre]

"1" means logic 1. So connect those pins to VCC via pull ups. If you don't, then the bootloader won't work properly.

[Brumy]

hi there. i'm need to create network with 2 p89c51rd2. The trouble is that ( and after following the datasheet ) it doesn

[Andy Ayre]

If it's a programming problem, then it is best to post your question at 8052.com, but provide as much specific information as you can. What your setup is, what you have tried, what steps you have taken to pin the problem down, etc. etc.

[mahesh h. bhendarkar]

  i want winisp sofrware from it will get .
   winisp software for philips microcontroller

[erikm]

i want winisp sofrware from it will get .

translated "I want problems"

use FlashMagic, it is soo much "safer"

Erik

[Andy Ayre]

WinISP has been replaced by Flash Magic. If you manage to find a copy you will find that (along with the bugs) it only supports old Philips devices.