Freescale Semiconductor SC140 specifications Rule A.1a, Example 7-86. Mctl Write to R0-R7 Use

Models: SC140

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Dynamic Programming Rules

Rule A.1a

AGU instructions that read the R0-R7 registers with an address register update or address pre-calculation, or as an operand affected by a MCTL modifier field are not allowed at the first 2 cycles of an exception service routine. This rule does not apply to R8-R15, or to R0-R7 using the no update (Rn) addressing mode.

Example 7-86. MCTL Write to R0-R7 Use

; ISR Start

;use MCTL, not allowed

move.w (r0)+,d0

; ISR Start

 

nop

;use MCTL, not allowed

move.w (r0)+,d0

; ISR Start

 

nop

 

nop

;use MCTL, allowed

move.w (r0)+,d0

; ISR Start

;use MCTL, not allowed

adda r0,r1

; ISR Start

;use MCTL, not allowed

move.w d1,(r0+n0)

; ISR Start

;use MCTL, not allowed

move.w (r0)+,d0

; ISR Start

;use MCTL, not allowed

move.w (r1)+,d0

; ISR Start

;use MCTL, not allowed

move.w (r5)+,d0

; ISR Start

;use MCTL, not allowed

adda r8,r1

; ISR Start

;no modifier mode, allowed

adda r1,r8

; ISR Start

;use MCTL, not allowed

adda #$1234,r8,r1

; ISR Start

;no modifier mode, allowed

adda #$1234,r1,r8

; ISR Start

;no update mode, allowed

move.w (r0),d0

; ISR Start

;no modifier mode, allowed

move.w (r8)+,d0

SC140 DSP Core Reference Manual

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Freescale Semiconductor SC140 specifications Rule A.1a, Example 7-86. Mctl Write to R0-R7 Use