Dear Friend,
Can we program the device, P89C51RD2BN from, 'org 0', if not then why...plz help.
Sudip Chatterjee
You can program any locations of the Flash memory. But it has to be erased first.
when i try to erase it...flash magic hangs...why is it so?
I sent you an Email. Did you get it?
Dear Friends,
I tried to program P89C51RD2BN but it programs for once.Next time when I do the same thing it does not go into the program mode.Why is it so?Do P89C51RD2HBP and P89C51RD2BN are different?Secondly the baud rate always goes down.
If any one can tell me,it will be of great help.
Thanking you,
Regards,
Debajyoti.
Being able to program a device for the first time only usually means that you do not have the hardware conditions for ISP entry correct. Double-check the voltages on /EA, /PSEN and /RST during reset to make sure they are as the datasheet requires them to be. /EA should be pulled high I believe.
Dear Mr.Andrew Ayre,
Thanks a lot for your quick reply.I will check out the datasheet.
Sir can you tell me one more thing.I have programmed P89c51RD2HBP. It does't creat any problem to me during Re-programming.But recently i have bought P89c51RD2BN which is giving me the problem.Please help me.
1> Cann't I program both the controllers with the same board?
2> Do they differ?
3> Do I have to make seperate board (PCB) for P89c51RD2BN?
Regards,
Debajyoti Chatterjee
The RD2xx requires a reset circuit workaround that you will find on the errata sheet for the device. If you have already done this then you can use the same hardware, otherwise you will need to make that modification.
Yes, these devices have a lot of differences. The pinout is the same, but one defaults to 6 clocks/cycle, the other to 12 clocks/cycle, one has smaller block sizes than the other, etc, etc.
You must select the correct device in Flash Magic!
Dear Mr.Ayre,
Thanks again.I read your reply.I have made the circuit as you mentioned but with no success.I used to program the P89c51RD2HBP controllers with the same board.But when I am trying to Program P89c51RD2BN,I could program it for once.Next time it does not goto the program mode.But this was not with the case of P89c51RD2HBP,where I can re-program the same controller.
Please help.
Dear Friends,
I am looking forward the answer to my problem.Please help me.
I have already tried many ways and went through the documentation and errata notes and made the changes.but still.....
bye
Dear Mr.Andrew,
I am still waiting for a answer from you.I have tried all combination and perputation but couldnot yet find any solution.One more problem that I am facing is that even when its programmed for once the baud rate i asked for is not being generated.I set it for 19200 but its connecting at 9600.I also set the CKCON bits so that it works at 6 clk/cyl but its working at 12.I am using crystal 0f 11.0592 Khz.set my TH1=253.
most serious is that i am unable to program it for next time.
Please revert back to me with all above question that I have put accross as soon as possible.
Thanking you,
Regards,
Debajyoti.
OK, so you have added the reset circuit workaround to your hardware, and you can program an Rx2Hxx ok but not an Rx2xx. Correct? Please work through the Flash Magic application note "what to do when ISP does not work" to try and narrow the problem down a little further.
Hello Friends,
I could successfully reprogrammed P89C51RD2BN.
For this the only thing I have done is the RC (R = 3K3,C=10microfarad) connection at pin Vpp. I am using Flashmagic ver1.99
Thanks,
Swati
swati i want some information about 89c51rd2bn
you connet rc to vpp pin
how you connet supply or ground send detail.
girish_deshpande@mail.com
i am new in programing for p89c51rd2bn in c.
please send some documentary so that i can understand this ic
send some documentary
well, you found this site -- use it
Erik
to
89c51 expert group
dear sir
i am used to deal with an old variant rd2hbp, but now only rd2bn is available in market, i have no other option, but it gives me lots of problems. i am using simple hardware to program chip with /EA is tied with Vcc(+5V) & /PSEN is made low for programing. ALE & P2.7 are kept floating.the newly purchased chip was programmed well for 4-5 times using flash magic but then after it starts giving problems. the chip can be programmed, as it seems, but does not execute user code. iam using max232 cpe. this has happened to me for 5-6 chips. pls. guide me about where the problem lies. is this happened b'cos P2.7 is kept open or any thing else.
RST pin is connected to Vcc through 0.1 uF capacitor (as in datasheet)t swich is placed. is any further modification required in reset then suggest.
looking for your quick reply.
thanks a lot
shabbir
Hold PSEN LOW, Tie it to ground during programming.
Hold RST for 0.5s,
Run Flash magic.