In message <001501c3b69b$04b25cd0$0b00a8c0@PAARD> Wouter van Ooijen wrote: > 1. Wisp628 has (for good reasons) series resistors in all its control > lines to the target PIC, so if the LCD somehow drives the line it will > probably win (without anyone loosing its smoke). Makes sense. > I always put a 2k2 > resistor between the PIC and the LCD in the releveant lines (RB6, RB7, > LVP), I recall some problems before I did this. Probably any value from > 1k up to 100k or so will work. I'll try that on the crystal, but I know it won't make any difference. It looks like a POR reset (i.e. poweroff/poweron) is the only way to clear the T1OSCEN flag once it's been set (that or clearing it in software). FWICT, the oscillator is getting enabled, but the PIC's ICSP engine is never clearing it, so the aforementioned PIC has no way of talking to the outside world (because the PGC/PGD lines have been taken up by the xtal). I've created a little workaround routine that is run every time the PIC initialises after an MCLR reset. The routine checks to see if RB1 is low and, if it is, it turns off TMR1 and crashes the PIC. > 2. Wisp628 (often) needs some additional circuit to re-program a PIC > that has its /MCLR configured as input. see > http://www.voti.nl/wisp628/index_1.html#dongle I'll see about building one of those later; I need to buy some 15-way female D-subs and some other bits first. A pack of CR2032s might also come in handy for when I've built the prototype :-/ Later. -- Phil. | Acorn Risc PC600 Mk3, SA202, 64MB, 6GB, philpem@dsl.pipex.com | ViewFinder, Ethernet (Acorn AEH62), http://www.philpem.dsl.pipex.com/ | 8xCD, framegrabber, Teletext For sale: One Russian space station. Needs minor repairs. -- http://www.piclist.com hint: The list server can filter out subtopics (like ads or off topics) for you. See http://www.piclist.com/#topics