BenLo Park
Microchess
Contact

The original 6502 Reference Card which shipped with the Kim-1 in 1976.

Programmers familiar with the 6502 instruction set will notice that there is no ROR (Rotate Right) instruction.

Early 6502 production chips did not include this instruction. Or, to be more precise, did not execute it correctly. Later, the bug was fixed and the instruction set was complete.

Microchess and the Kim-1