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I have noticed that a great deal of pages on the C64 Wiki refer to 'nnnn' as the operand for an instruction that accepts a relative address as an operand. The description then goes on to describe 'nnnn' as a 16-bit value.

I believe this is an error. The instruction is only 2 bytes long so it is impossible to have a 16-bit address. The value should be 'nn' where 'nn' is a signed 8-bit value. In the case of this BEQ, the instruction can jump +127, -128 from the address following the BEQ instruction.

See The Ultimate Commodore 64 Talk @25C3 for additional details. Can someone confirm this for me? -- Computerwiz 222

I changed the wording a bit. Apparently the "assembler format" column was talking about assembler syntax (which is distinct from opcodes and their operand formats). For example, see some disassembled code in VICE:
.C:c000 F0 10 BEQ $C012
I'd actually consider to remove the "In the syntax..." sentence as this is described better in the article about relative addressing anyways.
-- 1570 09:50, 12 February 2013 (CET)