This is a multi-part message in MIME format. --===============0487958629== Content-Type: text/plain; charset="windows-1250" Content-Transfer-Encoding: 7bit Well what a week that was last week. Finally got the time to build a small frequency generator device out of an 18F1220 to test another project I've been working on that needs a bit of debugging. I knocked up a small program and burned it into a 1220, hooked it all up and it was running well. Modified the program slightly, put the 1220 into my Promate II and hit the burn button - failure :( Erased device and tried again - same problem. Erased device and did a blank check - device not blank. Cycled power on both PC and Promate II - same problem. Tried with a 16F84A - worked fine - no problems. Tried with a brand new blank 18F1220 - same problem. Out came the trusty Picstart + with PUM module - now this doesn't normally program the 1220 without moaning and today was no exception - it wouldnt program the part and threw up loads of errors. Out with my last "virgin" 1220 and into the Picstart - same problem - errors on program but this would erase the device and blank check came up as device blank. Checking the "blank" PIC on the PM2 however showed it as having config bits set. Tried it on a different PC - same problem. Tried a working 1220 - I've programmed this at least 50 times without a problem but it failed again and killed the program in the PIC. Punched Promate II - didn't make any difference but felt a lot better. Decided to call it a day and retired from my workshop (a nice warm 38.7 degrees C) to the cooler environment of my house and cracked open a beer and settled down to browse the Microchip forums and Google for some inspiration. Came to the following conclusions : I might have a duff batch of 1220's It might be too hot in the workshop for the kit to program properly I might have a duff Promate II I might be doing something very wrong in the heat through sheer stupidity I might need to put between 0.1uF and 1uF in parallel with the PIC pins My version of MPLAB (7.21) might be buggy God might want me to have this week off and maybe the next one as well So ............... This morning I forced myself back into the workshop - a nice cool (!) 29.1 degrees C at 9am. Found a 1220 in my parts drawer from a different batch and tried that - same problem. This rules out heat and the 1220's themselves Went through everything in the software with a fine tooth comb - nothing had been changed. Upgraded to MPLAB 7.40 - same problem Tried with various values of capacitor between the supply pins - same problem Just about to give up at this point and have my 10am can of beer when I had a flash of inspiration - I took out the programming module on the PM2, cleaned the contacts and zebra strip with some Video head cleaner, took out the zebra strip and holder, cleaned the contacts on teh PM2 itself as well as the other side of the zebra strip, reassembled and hey presto all working again. Just erased, blank checked, programmed, verified every single 1220 that I had a problem with and they are all fine. Well worth cleaning all the contacts and zebra strips if you start getting random program and verify errors on the Promate 2. -- No virus found in this outgoing message. Checked by AVG Free Edition. Version: 7.1.394 / Virus Database: 268.10.1/389 - Release Date: 14/07/2006 --===============0487958629== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist --===============0487958629==--