Patience. Posting a question in the middle of international holidays, or weekends, or in the festive season and expecting immediate replies is being a little optimistic - especially as some of your questions require a little more than a quick two-minute answer!!! I will get around to answering your previous question with time.

>whats the difference between these two?
ADCON1 = %00001011
ADCON1 = 4

I assume you're using a 16F877... please download the datasheet and look in section "11.0 Analogue to Digital Converter Module" - it's right at the start of that section.

>option_reg = $7f
OPTION_REG.7 = 0 'Enable PORTB pull-up
what does $7f do, anyone who can show me something like the one above.

Again look at the OPTION_REG in the PIC's Datasheet. You will find it in the "Memory Organisation" section 2.2.2.2... Adobe provided you with a search facility within the Acrobat Reader if your Datasheet differs from mine.... However $7F is in binary %01111111, bit 7 is zero, all the other bits are one. Cross-check the setting of those bits against the table in the Datasheet detaling each bit of OPTION_REG.

Melanie