k8048 write errors

[gresh]

Hello. Great site. Very informative.

I've recently purchased a K8048 which when i try to write to the chip 16f627 or 16f628 i keep getting write errors. A typical error will say "write error at 0000. Wrote: 280A rEAD 3FFF". I believe the hardware is o.k. LD7 is strong showing power, LD9 is flashing brightly when sw5 is in PROG mode, and LD8 is on showing read/ write activity? when sw5 is in prog mode.

The only hardware problem i did have was with the rs232 serial adaptor. I didn't have a 9pin skt on the back of the PC. I am using a USB to serial port adaptor and the program "progpic2" is telling that it DOES detect the K8048 at the required com port.

It does seem as if the program is trying to write to the chip but im not having success cos of the read/write errors.

Any ideas anyone????

[Tomi Engdahl]

I didn't have a 9pin skt on the back of the PC. I am using a USB to serial port adaptor and the program "progpic2" is telling that it DOES detect the K8048 at the required com port.

The problem could be related to that USB->RS-232 adapter.

Not all USB-RS232 adapters are alike, and all of them work much worse than real serial ports what comes to RS232 interfacer handshaking signals. Just basic serial data might get through acceptably, bu then you need more complicated things related to handshaking signals, those adapters fill fail sooner or later... According to some of my collegues many USB-RS232 adater ICs used on those products have bugs serious in their hardware and/or their software drivers in what comes to the RS232 handshaking signal handling.

And this PIC programmer relies quite heavily on the use of the RS-232 handshaking signals to carry different control information to the programmign card.

[gresh]

Thanks for the advice. I did wonder if the USB serial adaptor might be causing problems. I do have an old PC with a 9 pin serial port so i shall try using that and see if it works.