problems with P89C51RD2BA

[Bob Bailey]

I have tried the capacitor on PSEN,  the chips are still reluctant to enter boot mode when reprogramming.  I can use some 'reboot' routines, inspired by your stuff but different, for reprogramming.

The issue I am speaking of is that **new** chips give me the FlashMagic error message, indicating (I believe) that they never entered boot mode.

If I reset them with PSEN low, I can convince them to enter boot mode.
sometimes it takes an extra reset pulse (pushbutton) or some other button sequence.

I am building a device with no PSEN hardware, and want to ISP it with the initial program, and use the 'reboot' feature for software update.

Perhaps my problem is a flaky reset (RC, I know) or user error with FlashMagic.

I was hoping that someone else had experienced this.

Thanks for your help, Eric.  Does the above clarify my earlier post?
(a tech-writer I am not.)

Regards,

[Bob Bailey]

I just changed the crystal on my WinISP board from 22.1184 to 11.0592

It seems to work much better,  in fact I have not been able to get it to fail.


Time will tell.  Perhaps the 22mhz crystal was out of spec, or weak......

Regards,  

Bob

[erik malund]

I just changed the crystal on my WinISP board from 22.1184 to 11.0592
The 6 clock mode is specified only to 20MHz, maybe something here?

Erik

[bob bailey]

I was thinking the autobaud routines didn't work well that high....

Or, I had FlashMagic set to 22, not 22.1184....... that might be it.

It seems to work now,  thanks for the input.

BTW, I think I mentioned on 8052.com,  my REBOOT routine is very similar to your NoTouch stuff but doesn't reset the Status Byte.  It just triggers the ISP mode.  That way if the mode is triggered accidentally the system will recover with just a reset.  Thanks for the inspiration!

Oh, and what gotchas am I going to face using an RC reset.  You mention it often, but  I didn't turn up any threads with the search function.  Is there a good+cheap 3-terminal (TO92) supervisor chip that you like?  

Regards,

Bob

[erik malund]

Is there a good+cheap 3-terminal (TO92) supervisor chip that you like?
I use the MAX810.  A funny thing about this MAXim chip is that it is usually easier to get form Philips than Maxim.

Erik

[bob bailey]

thanks

Bob

[Kench]

Dear ALL,
     I have meet the same problem that can program the P89C51RD2BB only once. The Flashmagic display connect error when i try to reprogram the P89C51RD2BB.
     I have do the ternimal test.The result is "the 'U' is arriving at the RxD,but no 'U' leaving the TxD".
     HELP ME!!!
Thks!
kenchbob bailey wrote:

> thanks
>
> Bob

[Kench]

Add the RC at the PSEN can slove the problem.

thank everybody!!!

[Santhi Karthikeyan]

We have the same problem with our board with RD2BA . We have tried all the solutions suggested above but the chip is not getting reprogrammed. I have Eric's boot loader also in the first software fused in the device. But nothing seems to make the chip enter ISP. Delayed PSEN as suggested with resistor- capacitor also is of no help. However I have seen 2 or 3 other RD2BA devices working smoothly. This first sample for production is now stuck with the problem. Immediate help/ suggestions in this regard shall be helpful. I have tried Flash Magic and Win ISP also.
Thanks in advance

Santhi

[pra_mulay]

Hello,

while erasing, slect hex block erase only.

this change will make you clock mode as otp.

thanks

[Andy Ayre]

Santhi - I would look at the VCC voltage to the non-functional device to make sure it is stable and glitch free. Also check the signal at the XTAL pins and make sure it is stable and the expected frequency. Glitches on the power supply can cause problems for the crystal and stop the device from functioning properly.

[venugopal]

What are the settings for 89c51RD2ba to function like 89c51RD2HBA  by using ISP programming.

[Andy Ayre]

The RD2BA cannot function like an RD2HBA because the flash block size is different, therefore different commands are required. Just make sure you select the correct device in Flash Magic.

[Venugopal]

The chip is being programmed and once it is plugged into the target board only the ports are working and nothing is working like memory access,lcd etc. are not working including the RS232 port.  

thanks

[chander_k@epatra.com]

Errors faced while uploading the file through FLASH MAGIC
1.