Constants used to identify pins in the header files?

[Tom-H-PIC]

How does this number work?
I have tried all the ways that I can think of to get this number.
Like for Pin_B3 for the 18F4550 this is at address F81.2
The header file has 31755?
Thank all Tom

[kamputty]

F81.2 = memory address F81 bit 2

F81 HEX = 3969 DEC


31755 = number of BITS, so the byte is 31755/8 = 3969.38 or 3969 BYTES with a remainder of 3, or the 3rd bit.

The numbers in the header file are BIT based (at least the pins!)

Yes?

~Kam (^8*

[Ttelmah]

The number, is the register address, times 8, plus the bit number. Pin B3, is 0xF81.3, not 0xF81.2.
0xF81, is 3969 in decimal. Times 8 gives 31752. Add three for the bit number, gives 31755.

Best Wishes

[Tom-H-PIC]

I knew that it had to be straight forward.
Thank
Tom