section 7 - Index of

section 7 - Index of section 7 - Index of

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JSCLR Jump to Subroutine If Bit Clear JSCLROperation:Assembler SyntaxIf S[n]=O,JSCLR #n,X:ea,xxxxthen SP+ 1-+SP; PC-+SSH; SR-+SSL; XXXX -+PCelse PC+1 -+PCf S[n]=O, JSCLR #n,X:aa,xxxxthen SP+ 1-+SP; PC-+SSH; SR-+SSL; xxxx-+PCelse PC+ 1-+PCIf S[n]=O, JSCLR #n,X:pp,xxxxthen SP+ 1-+SP; PC-+SSH; SR-+SSL; xxxx-+PCelse PC+ 1-+PCIf S[n]=O, JSCLR #n,Y:ea,xxxxthen SP+1-+SP; PC-+SSH; SR-+SSL; xxxx-+PCelse PC+ 1-+PCIf S[n]=O, JSCLR #n,Y:aa,xxxxthen SP+1-+SP; PC-+SSH; SR-+SSL; xxxx-+PCelse PC+ 1-+PCIf S[n]=O, JSCLR #n,Y:pp,xxxxthen SP+ 1-+SP; PC-+SSH; SR-+SSL; xxxx-+PCelse PC+ 1-+PCIf S[n]=O, JSCLR #n,S,xxxxthen SP+1-+SP; PC-+SSH; SR-+SSL; xxxx-+PCelse PC+ 1-+PC-Description: Jump to the subroutine at the 16-bit absolute address in program memoryspecified in the instruction's 24-bit extension word if the nth bit of the source operand S isclear. The bit to be tested is selected by an immediate bit number from 0-23. If the nth bitof the source operand S is clear, the address of the instruction immediately following theJSCLR instruction (PC) and the system status register (SR) are pushed onto the systemstack. Program execution then continues at the specified absolute address in the instruction's24-bit extension word. If the specified memory bit is not clear, the program counter(PC) is incremented and the extension word is ignored. However, the address register

JSCLR Jump to Subroutine if Bit Clear JSCLRspecified in the effective address field is always updated independently of the state of thenth bit. All address register indirect addressing modes may be used to reference thesource operand S. Absolute short and I/O short addressing modes may also be used·Restrictions: A JSCLR instruction used within a DO loop cannot specify the loopaddress (LA) as its target.A JSCLR located at LA, LA-1, or LA-2 of a DO loop, cannot specify the program controllerregisters SR, SP, SSH, SSL, LA, or LC as its target.JSCLR SSH or JSCLR SSL cannot follow an instruction that changes the SP.A JSCLR instruction cannot be repeated using the REP instruction.Example:JSCLR #$1 ,Y:«$FFE3,$1357;go sub. at P:$1357 if bit 1 in Y:$FFE3 is clearExplanation of Example: In this example, program execution is transferred to the subroutineat absolute address P:$1357 in program memory if bit 1 of the external I/O locationY:«$FFE3 is a zero. If the specified bit is not clear, no jump is taken and theprogram counter (PC) is incremented by 1.-

JSCLR Jump to Subroutine if Bit Clear JSCLRspecified in the effective address field is always updated independently <strong>of</strong> the state <strong>of</strong> thenth bit. All address register indirect addressing modes may be used to reference thesource operand S. Absolute short and I/O short addressing modes may also be used·Restrictions: A JSCLR instruction used within a DO loop cannot specify the loopaddress (LA) as its target.A JSCLR located at LA, LA-1, or LA-2 <strong>of</strong> a DO loop, cannot specify the program controllerregisters SR, SP, SSH, SSL, LA, or LC as its target.JSCLR SSH or JSCLR SSL cannot follow an instruction that changes the SP.A JSCLR instruction cannot be repeated using the REP instruction.Example:JSCLR #$1 ,Y:«$FFE3,$1357;go sub. at P:$1357 if bit 1 in Y:$FFE3 is clearExplanation <strong>of</strong> Example: In this example, program execution is transferred to the subroutineat absolute address P:$1357 in program memory if bit 1 <strong>of</strong> the external I/O locationY:«$FFE3 is a zero. If the specified bit is not clear, no jump is taken and theprogram counter (PC) is incremented by 1.-

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