© 2000 Scenix Semiconductor, Inc. All rights reserved. 121 SX User’s Manual Rev. 3.1 www.scenix.com Chapter 3 Instruction Set 3.6.51    SNB fr.bit Test Bit in fr and Skip if Clear Operation: Test a specified bit in fr; if 0, skip next instruction Bits affected: none Opcode: 0110 bbbf ffff Description: This instruction tests a bit in the specified file register. The file register address (00h
through 1Fh) and the bit number (0 through 7) are the instruction operands. If the
bit is 0, the next instruction in the program is skipped. Otherwise, program execu-
tion proceeds normally with the next instruction. Cycles: 1 if tested condition is false, 2 if tested condition is true Example: snb $1F,5 ;test bit 5 of file register dec $1F ;decrement if bit=1 mov W,$1F ;move file register to W This  example  tests  bit  number  5  of  file  register  1Fh.  If  that  bit  is  0,  the  “dec” instruction is skipped. Otherwise, program execution proceeds normally with the
“dec” instruction.