Andy, I was referring to the situation where you are attempting to use an analog-configured pin as a digital output, which is what I thought Tony was asking about ??????????? BTW, tell me why I can't ever get my hands on any Cypress FIFOs. Nobody ever seems to have them. Has Cypress stopped manufacturing them? - danM ====================== >Dan Michaels wrote: > >> > Analog pins always read as '0', so '0' gets written back >> > regardless of the output state, and I was using BSF, BCF. >> >> I think this is not exactly correct. > > No, it is exactly correct. > >> If you only exercise a single pin uisng BSF/BCF, it will work >> correctly.... > > But it will have side-effects on any other pins within the port > which are configured as analog inputs and digital outputs. > >> .... but if you do successive BSF/BCFs to > 1 PortA pins, then only >> the last will be operated upon corrrectly, and all others will >> always end up being cleared. > > Not true. When that happens, it's because of the circuitry > OUTSIDE the PIC, not because of any limitation inside the PIC. > >> BSF PORTA, 0 >> BSF PORTA, 1 >> BSF PORTA, 2 >> >> will leave the port in the following state: xxxx'x100 > > Not if RA0, RA1, and RA2 are disconnected from any outside > circuitry... Or if the PIC is running at a low clock speed. > > -Andy > > >=== Andrew Warren -- aiw@cypress.com >=== Staff Applications Engineer >=== Interface Products Division >=== Cypress Semiconductor >=== >=== for tech support: >=== usbapps@cypress.com > >-- >http://www.piclist.com hint: The PICList is archived three different >ways. See http://www.piclist.com/#archives for details. > > > > > > -- http://www.piclist.com hint: The PICList is archived three different ways. See http://www.piclist.com/#archives for details.