Author Topic: problem connecting p89v51rd2fn with usb 2 serial cable  (Read 4587 times)


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problem connecting p89v51rd2fn with usb 2 serial cable
« on: September 24, 2009, 07:37:41 pm »
hello  every one...
I am using a 8051 programming board.Which has a rs232 b/w the controller and the db9 connector.
I had used 89v51rd2bn earlier on this board. with flash magic and programmed it through a serial port.

now I have upgraded my pc.but dont have a serial port ,so have bought a serial2 usb conector.
and I  want to flash 89v51rd2fn(could not find 89v51rd2bn in the market) with the same board.
as i am using a usb2serial converter it gets connected to COM3 port (as shown in device manager).
following are the flash magic setting i have used:
Baud Rate 9600
device :89v51rd2
interface :nonce(isp)
unckeched DTR &RTS while com port is open
checked erase bolcks used by hex file.
I am attaching the debug file
please check.
while debugging i have read the device signature:
error msg with com1 selected:unable to connect to device,try reducing the baud rate.
error msg with com3 selected:unable to connect,(configure )ensure no  other application is using com port ,try raising or lowering the baud rate.

Andy Ayre

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Re: problem connecting p89v51rd2fn with usb 2 serial cable
« Reply #1 on: September 25, 2009, 09:26:16 am »
Flash Magic sends out the autobaud character 'U' and doesn't get a response.

Go to Options -> Advanced Options -> Hardware Config and uncheck/untick "Use DTR to control RST". Then give it a try. Cycle the power to your board or reset the device when you are instructed to by Flash Magic.

If you still have problems then I would suggest you try a different USB-RS232 cable.

Note that you must select the correct COM port for your cable. If it appears as COM3 then you must use that. Try unplugging it and plugging it back in while watching the list of ports in the device manager.

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