Cannot connect 89C51

[hermeshome]

Hi all,

I have try to use FlashMagic to connect my board with 89C51RA2BN. However, FlashMagic alway show this "Unable to connect at specified baud rate. Try reducing the baud rate. Reset the hardware into ISP mode again." I have check COM port, cable in my home PC, they are normal. And I have check with the shop that I buy the board, the shop owner can program the board. Why I can not do anything with my board and PC.

Can anyone help me?

[Jan Waclawek]

- run a terminal program (I prefer terminal by Bray rather than hyperterminal) 9600/8N1, no handshake (and no local echo o hyperterminal)
- remove the P89C51RA2 from socket (I hope it is socketed) and short Rx and Tx pins in the socket. Type anything, it should echo back. This checks the serial chain (COM port in PC, cable, MAX232, PCB etc.)
- put the chip back. Make sure the hardware conditions (/EA, /PSEN, RESET) are met for starting the bootloader. I hope you have a proper reset generator (invalid reset may result in "wonders"). Make sure the oscillator works (using oscilloscope or counter).  Type "U", it should echo back "U"
- if it does not, it may be the infamous "boot vector lost". Go back to the shop where you bought it and ask (politely) the owner for help.

Jan Waclawek