-----Original Message----- From: Dean To: PICLIST@MITVMA.MIT.EDU Date: Saturday, December 13, 1997 22:22 Subject: 16C84 RA4 Question. >Is there a trick to make the RA4 pin on a 16C84 an output. >I have the PIC connected to an 8 BIT ADC, if I read the ADC and >then send a HI to either RA0 throught to RA3, depending on >the value recieved from the ADC, > >0 to 63 = HI on pin RA0 only. >64 to 128 = HI on pin RA1 only. >129 to 191 = HI on pin RA2 only. >192 to 255 = HI on pin RA3 only. > > >everything works fine, BUT when I try and use RA4 as well, > >0 to 50 = HI on pin RA0 only. >51 to 100 = HI on pin RA1 only. >101 to 150 = HI on pin RA2 only. >151 to 200 = HI on pin RA3 only. >201 to 255 = HI on pin RA4 only. Yes there is, the RA4 pin when in output mode only is capable of pulling a line low, it has no transistor (or whatever) for pulling the line high (BTW great for I2C). To get a high, connect a 10k (value not critical) to RA4 and VCC, then you should get the right logic out of it. TTYL