Post by thread:In-system serial programming (?)

Admittedly I am still figuring things out here ... but let me ask this question ... Why is David Tait's 16C84 programmer only labeled as for 16C84's? Other PIC's have in-system serial programming! Isn't it just a question of software? Why couldn't I use David Tait's programmer to program a 16C74? Albert

> > Admittedly I am still figuring things out here ... but let > me ask this question ... Why is David Tait's 16C84 programmer > only labeled as for 16C84's? Other PIC's have in-system serial > programming! Isn't it just a question of software? > > Why couldn't I use David Tait's programmer to program a > 16C74? One word: EEPROM See the 16C84 EEPROM is self timed on the write. So once you send a begin programming command it'll stop programming automatically. All the other parts however use EPROM. So the programmer is obligated to send a STOP programming in addition to the BEGIN program command. I believe that the time is only 100 uS pulses which is difficult to get with any accuracy in software. Best bet would be a 16C84 that would handle the task easily. It can be self programmed and then the programm driven by a 16C84 could programm all the other parts. Later, BAJ