vref pin & hardware reset for at89c5131
my problem is like this:
most of the time , my laptop cannot identify the usb as the AT90S5131..
just occasionally, my laptop identified it , which happen only twice...
after my laptop can identify it, i can programme it then...
now tat my laptop cant identify it..
could it be the problem of my laptop usb port?
coz 1 of the usb port i use for programming like disable ady..no response at all...
i think the circuit shouldnt be a problem coz my laptop can identify it before..
any1 can help here?