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Dave Moll · 28th May 2019, 3:33 pm

In the 6502 instruction set, conditional branches (various Bxx) are always by a displacement of up to ±127 bytes, whereas the unconditional jump (JMP) is to a two-byte address (i.e. to anywhere within the 64KB memory space).

The 6809's BRN and LBRN are presumably used in the same manner as the no-operation (NOP) of the 6502.

28th May 2019, 3:33 pm	#5
Dave Moll Dekatron Join Date: Feb 2005 Location: West Cumbria (CA13), UK Posts: 6,127	Re: Fun with 6502 Assembler In the 6502 instruction set, conditional branches (various Bxx) are always by a displacement of up to ±127 bytes, whereas the unconditional jump (JMP) is to a two-byte address (i.e. to anywhere within the 64KB memory space). The 6809's BRN and LBRN are presumably used in the same manner as the no-operation (NOP) of the 6502. __________________ Mending is better than Ending (cf Brave New World by Aldous Huxley)