Author Topic: Problem to program 89C61X2  (Read 2657 times)

wah

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Problem to program 89C61X2
« on: June 17, 2004, 09:02:22 pm »
Hi,

I want to program 89C61X2. When I try to read security bits, Flash Magic has a message "Unable to connect at a specified baud rate. Try reducing the baud rate. Reset the hardware into ISP mode again." I already use the lowest baud rate. Why the MCU cannot be connected?

You can go to page 13
http://www.keil.com/dd/docs/datashts/philips/p89c6xx2_ds.pdf
and page 17
http://pdfserv.maxim-ic.com/en/ds/MAX220-MAX249.pdf
to see my schematic.

Also, I connected pin2 of DB9-F to pin14 of MAX232,
pin3 of DB9-F to pin13 of MAX232,
pin5 of DB9-F to GND.