Author Topic: 89v51 isp problem  (Read 7015 times)

sanjayporwal

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89v51 isp problem
« on: September 26, 2012, 01:00:28 pm »
Hi,

Used Flash Magic to program a P89V51RC2 in ISP Mode;

When I execute command READ DEVICE SIGNATURE, it gives the error:

"Operation Failed.(reading signature)" or "UNABLE TO COMMUNICATE.(Tx/Rx)..."

I replaced my 89v51rd2 with 89s52, 89c52 and 89c52 but all the time getting same message and many times it hangs at "Reset device into ISP mode now" even after resetting it by hardware.

looking forward for your help.

thanks

sanjayporwal

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Re: 89v51 isp problem
« Reply #1 on: September 26, 2012, 01:05:04 pm »
DTR and RTS chechbox is unchecked.
COM 1
9600

and I have used the same 89v51rd2 many times in past. So I think my controller is ok.

Andy Ayre

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Re: 89v51 isp problem
« Reply #2 on: September 27, 2012, 01:06:11 am »
The devices you tried are not interchangeable.

Make sure you selected the 89V51 when you had it connected to Flash Magic. If you selected one of the other devices you mentioned then you might have put it into SoftICE mode (details of this are available on other websites).

Put a scope on the RxD and TxD pins and confirm the 'U's are receiving the device and it is transmitting a 'U'.

Test the autobaud in Hyperterminal.

Andy
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