6502 Shorts. By Lee Davison.

Introduction.
This section is for those short bits of code that are just what you need every now and then.

Anything longer than $20 bytes should probably be elsewhere.

The code.

Toggle carry - Change the sense of the carry bit. BCD to binary - Convert a BCD byte to binary.
Range test - Test a byte is in the range n to m. Binary to BCD - Convert a binary byte to BCD.
Check CMOS - Test if code is running on a 65C02. Hex to ASCII - Another way to convert a hex nibble.
Save XY - Push/pull X & Y without using A. Eight bit rotates - One bit less in ROL or ROR.
ASL & ASR - A true arithmetic shift left and right. Sign extend - Extending a less than 8 bit value to 8 bits.


Last page update: 23rd April, 2006. e-mail me