Messages

I find the answer.

Don't kick my ass , please. ^_^

I have 4 p89c61x2. But 3 chips need parallel programmer to "fix".

And only one chip use FM normally every time.

Thank you very much for  your kindly to help me .

Best Regards,
Patrick.

I have 4 P89C61 chips.

But only write once and could not into isp mode again every chip.

I want to understand what's going on .

I think that PSEN and RESET timing issue to make the problem.

thanks , erikm.

Best Regards,
Patrick.

Signal 1 => RESET
Signal 2 => PSEN

voltage = 5V
Time/div for error_reset.jpg is 1second
Time/div for normal_reset.jpg is 500ms

thank you , Andrew Ayre.

Thank erikm , NoTouch is a pretty good idea .

But I already build the ISP Tool , and only one 89c61x2 can't  into ISP mode that can't burn NoTouch.

Does anyone have experience that adjust from Error reset to Normal.

Normal reset
http://www.usync.tzo.com/right_reset.jpg

Error reset
http://www.usync.tzo.com/error_reset.jpg

I've try adjust T1 and T2  that can't into isp mode .

Flash Magic generate PSEN and RST Signal not stable for reset every time.

My hardware . P89C61X2

PC win98 :

I use the oscilloscope to find wave edge width not stable

Normal reset
http://www.usync.tzo.com/right_reset.jpg

Error reset
http://www.usync.tzo.com/error_reset.jpg


I use the same hardware , but some time could reset 89c61x2 , and some time wrong.

Could you give me some advice

Thank you.

Best Regards,
Patrick Chiu

I found the answer , in previous topic ,


DTR RTS , need a MAX232  convert  to TTL voltage level .

Thanks, Andrew Ayre .

You are very kindly that answer my question.

^_^

Best Regards,
Patrick Chiu

Hi I have a question ,

Does RS232 pin RTS, DTR need a MAX232 that convert to TTL voltage level?

Thanks.

Patrick Chiu

I use "Flash Magic Application Note 1", Figure 1 to build my ISP Tool

and have some problem.

In "Flash Magic Application Note 1", tell me that when the com port is closed , RTS and DTR are at a RS232 voltage level below -3V.

But when I put every thing together and power on .

PSEN always Low, and RST alway high.

I found DTR, RTS on 0.7V

this is my circuit diagram

http://www.usync.tzo.com/fm_isp.pdf

PSEN pull up 10k , and  RST 10uF, 10k at other page.

This problem is confuse me serval day .

Have anyone can tell me how to do ? :-(

Thank you very much .

Patrick Chiu.