oh....I saw a web page mention that the pic16f877 did have an internal oscillator. Oh well. I'll look into how to make an apparopriate RC circuit. Thanks. --- In , "rtstofer" <rstofer@p...> wrote: > > You already know the answer: the 16F877 does not have an internal > oscillator. You can use an RC circuit, a low or high frequency > crystal or ceramic resonator. > > See section 12-2 of the datasheet. > > --- In , a_drunken_dwarf <no_reply@y...> > wrote: > > Hi, I'm using IC-Prog to download a 'blink' hex file (supposed to > > make led's blink) to my PIC16f877. I've done successful downloads > to > > the PIC before (it's 'verfied' the code after it sent it to the > > PIC). However, the PIC doesn't flash LEDs after the program is > sent > > to it. I'm not using an external oscillator (hasn't arrived in the > > mail yet) an I think this is the problem, because the clock out > pin > > is constant high, and none of the io pins are pulsing (I used a > > logic probe). So I found out that the PIC16f877 has an internal > > oscillator that has to be 'turned on' in the configuration. IC- > Prog > > has a little configuration menu to select the type of oscillator, > > but for some reason it doesn't list INTRC (internal oscillator) in > > the menu of the PIC16f877. INTRC is listed in the config menus of > > other PIC's though! This is a bit irritating. Could anyone give > any > > advice? Thanks!

You already know the answer: the 16F877 does not have an internal oscillator. You can use an RC circuit, a low or high frequency crystal or ceramic resonator. See section 12-2 of the datasheet. --- In , a_drunken_dwarf <no_reply@y...> wrote: > Hi, I'm using IC-Prog to download a 'blink' hex file (supposed to > make led's blink) to my PIC16f877. I've done successful downloads to > the PIC before (it's 'verfied' the code after it sent it to the > PIC). However, the PIC doesn't flash LEDs after the program is sent > to it. I'm not using an external oscillator (hasn't arrived in the > mail yet) an I think this is the problem, because the clock out pin > is constant high, and none of the io pins are pulsing (I used a > logic probe). So I found out that the PIC16f877 has an internal > oscillator that has to be 'turned on' in the configuration. IC- Prog > has a little configuration menu to select the type of oscillator, > but for some reason it doesn't list INTRC (internal oscillator) in > the menu of the PIC16f877. INTRC is listed in the config menus of > other PIC's though! This is a bit irritating. Could anyone give any > advice? Thanks!

Hi, I'm using IC-Prog to download a 'blink' hex file (supposed to make led's blink) to my PIC16f877. I've done successful downloads to the PIC before (it's 'verfied' the code after it sent it to the PIC). However, the PIC doesn't flash LEDs after the program is sent to it. I'm not using an external oscillator (hasn't arrived in the mail yet) an I think this is the problem, because the clock out pin is constant high, and none of the io pins are pulsing (I used a logic probe). So I found out that the PIC16f877 has an internal oscillator that has to be 'turned on' in the configuration. IC-Prog has a little configuration menu to select the type of oscillator, but for some reason it doesn't list INTRC (internal oscillator) in the menu of the PIC16f877. INTRC is listed in the config menus of other PIC's though! This is a bit irritating. Could anyone give any advice? Thanks!