SX User’s Manual Rev. 3.1 64 © 2000 Scenix Semiconductor, Inc. All rights reserved. www.scenix.com Chapter 3 Instruction Set 3.5 Equivalent Assembler Mnemonics Some  assemblers  support  additional  instruction  mnemonics  that  are  special  cases  of  existing
instructions or alternative mnemonics for standard ones. For example, an assembler might support the
mnemonic “CLC” (clear carry), which is interpreted the same as the instruction “clrb $03.0” (clear bit
0 in the STATUS register). Some of the commonly supported equivalent assembler mnemonics are
described in Table 3-7. 3.6 Detailed Instruction Descriptions Each instruction in the SX instruction set is described in detail in the following pages. The instructions
are described in alphabetical order by mnemonic name. Each description starts on a new page of the manual. The heading at the top of the page shows the
syntax of the command and a brief description of what the command does. Table 3-7  Equivalent Assembler Mnemonics Syntax Description Equivalent Cycles CLC Clear Carry Bit CLRB $03.0 1 CLZ Clear Zero Bit CLRB $03.2 1 JMP W Jump Indirect W MOV $02,W 4 or 3 (note 1) JMP PC+W Jump Indirect W Relative ADD $02,W 4 or 3 (note 1) MODE imm4 Move Immediate to MODE Register MOV M,#lit 1 NOT W Complement W XOR W,#$FF 1 SC Skip if Carry Bits Set SB $03.0 1 or 2 (note 2) SKIP Skip Next Instruction SNB $02.0 or SB $02.0 4 or 2 (note 3) NOTES:  1. The JMP W or JMP PC+W instruction takes 4 cycles in the “compatible” clock-
ing mode or 3 cycles in the “turbo” clocking mode. “Compatible” mode is avail-
able only in the SX18/20/28AC and SX18/20/28AC75 devices. 2. The SC instruction takes 1 cycle if the tested condition is false or 2 cycles if the
tested condition is true. 3. The assembler converts the SKIP instruction into a SNB or SB instruction that
tests the least significant bit of the program counter, choosing SNB or SB so that
the tested condition is always true. The instruction takes 4 cycles in the “compat-
ible”  clocking mode  or 2  cycles in  the  “turbo” clocking  mode. “Compatible”
mode is available only in the SX18/20/28AC and SX18/20/28AC75 devices.