On 2010-07-29 19:55, Joep Suijs wrote: > RA0 is also wired to the ICSP connector. I guess you have disconnected > the programmer? I thought about that and specificaly looked for it but I can not see that RA0/AN0 is connected to the ICSP connector. The ICSP connector has : 1: Vdd/Vpp 2: Vss 3: GND 4: ICSPDAT, RB7 5: ICSPCLK, RB6 6: AUX, RA4 How is RA0/AN0 connected to the ICSP connector ? > > Joep > > 2010/7/29 Jan-Erik Soderholm: >> >> >> On 2010-07-29 18:56, alan.b.pearce@stfc.ac.uk wrote: >>>> No, just the standard "PICkit2 Starter Kit" : >>>> http://www.microchip.com/pickit2/ >>>> >>>> The 28-pin demo board in that kit : >>>> http://ww1.microchip.com/downloads/en/DeviceDoc/41301A.pdf >>>> Scematic at page 9, the pot at the top of fig A-1. >>>> >>>> It's the voltage drop over R7 that is my concern. >>>> >>>> >>>> Jan-Erik. >>> >>> Well, I suspect we are at a point where something in your code is >>> setting RA0 to an output and setting it low, i.e. writing 0 to both >>> TRISA and PORTA. >> >> It's not "my" code. :-) >> >> The code is "lesson 4" in the PICkit2 low-pin-count demo code kit. >> I have put a copy of the actual code here : >> http://jescab2.dyndns.org/pub_docs/a2d_asm.txt >> >> I tried to do some minor adjustments (only enabling AN0, shutting >> WPU off and so on) but no changes at all. >> >> >> >>> >>> AIUI having a port bit set to analogue doesn't stop it being used as a >>> digital output port. This is used to advantage in some sneaky schemes >>> for doing things like making capacitance meters, by discharging the cap >>> and then using the A/D or comparator to measure the time it takes to ge= t >>> to a certain voltage. >>> >> -- >> http://www.piclist.com PIC/SX FAQ& list archive >> View/change your membership options at >> http://mailman.mit.edu/mailman/listinfo/piclist >> --=20 http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .