Messages

Thanks for reply.
No, it is not the case that you can not loos the bootloader. Due to your problematic circuitry bootloader can be lost!
Andy, as you told I have searched on NXP also but I couldnt get it. I think my P89C51RD2 lost its bootloader so I want to re program that. I know that bootloader can be re programmed but dont know from where to get it.

Regards,
Kirankumar

Hi All,
Could you please tell me that from where I could download bootloader for P89C51RD2BN chip?
I want hex file so that I could reprogram the bootloader to the IC.

Thanking in advance.

regards,
Kirankumar

Thanks everybody!!
my problem has been solved! actually it was the issue of VPP pin.
i have not connected it to VCC, insted of connecting it to VCC it was connected to GROUD on the PCB and also bootloader of my P89C51RD2 was get erased by mistake!!

Thanks again!

regards,
Kiran

aah!! ok ok!
actualy i got confused because in the same document (AN461) on page 12 they have given a schematic for typical ISP circuit, in that VPP is grounded through cap without connecting to the Vcc. i guess that is for c51RD+ microcontrollers!

thanks for fast reply

regards,
Kiran

Hi all,
I am new to this list.
I am using P89C51RD2BN, through ISP i am trying to program it. but it is not entering into ISP mode.  I am using FlashMagic to do programming. it is giving me error as "Unable to connect at specified boud rate. Try reducing the boud rate"!
I have made circuitry as per AN461, the only difference is that in the reset circuit i am using 8.2K resister instead of 10K specified in AN461. also EA/VPP line is kept floating but in AN461 they have shown that that pin is connected to ground through 0.1uF capacitor. is the problem i am facing is due to these differences?. I have a jumper for PSEN pin to put microcontroller in to ISP.
please help me.

looking for your reply!

thanking in advance,

regards,
Kiran