On Tue, Oct 12, 2004 at 01:12:37PM -0400, John J. McDonough wrote: > ----- Original Message ----- > From: "Dave VanHorn" > Subject: Re: [PIC] Programm pic16f628a > > > > One technique I've seen used, is to use the serial out data as a clock, > > sending either 0x00 or 0xff, with the handshake line as the data. This > > lets you work with clocked serial latches, and from there, you're > > bit-fiddlin again. > > Most seem to use serial out for MCLR. But with 8/N/1 your technique should > work if you send 0x0f. Well, depending on the speed I suppose the PIC > doesn't much care what the duty cycle is. You could get five times the speed > if you sent a5's. There's no way to sync the data in that situation. If you had some intelligent way of detecting bit length you could pack two or three bits per character transmitted. But this is a situation that probably best works by bootstrapping. The best serial interface is a PIC USART. But the catch 22 is programming the PIC. So a trivial serial programmer coupled with a subsequently programmed part would be the ticket. Kind of like the WISP628 but more generic. Silly question: Can you bit fiddle the handshake lines on a USB to serial cable? I ebayed real quick and saw that the cost of USB to RS-232 cables are around $12. I could almost live with that if I were sure that the handshake lines were twiddlable. BAJ _______________________________________________ http://www.piclist.com View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist