Cannot burn a 27c512. Binary loads, programming begins. Safety jumper is off. No external power supply hooked up to the burner. Goes through the "programming chip" phase of the burn, then produces the "error at 0x00000 chip=0xFF buffer=0x10" about 25 percent of the way through the verify. This is an older Willem PCB3 bought from MCUmall through eBay in 2005 and never used until now. No "version" markings on the burner board as far as I can tell or see. It is running 97ja on XP SP2 with the polling disabled on the parallel port on a Thinkpad 570E laptop. It came with 97ja.
How can this model be powered externally to program? The 27c512 chip requires 12.5 volts for a successful - reliable burn. I obtained a 13.0 volt regulated 800 milliamp power supply. The instructions that came with this burner do not show how to power it externally to get a strong voltage. (15 volts will likely damage the chip) I am uploading a picture of the burner I have from the instruction guide.
Check all DIP bit are set correctly. Also, check the VPP if it is correct. Vpp should be around 12V.
Vpp was low. 11.7 volts. HOWEVER, I got it to work by "hard setting" the IRQ in the laptop BIOS and using EPP mode instead of "normal" which is "bi-directional" which I also guess is ECP. I also made sure the port polling "legacy polling" was OFF in the Device manager LPT1 port properties. Before setting the IRQ I got "zero" voltage and erratic program mode led light operation on the board. After "hard setting" the IRQ to port 0378, it programmed and verified OK
cannot burn chip - error at 0x000000 chip=0xFF
Posted - 12/15/2007 : 16:15:04
