MCF548x Reference Manual, Rev. 3
8-58 Freescale Semiconductor

Table 8-31 shows the PSTDDATA specification for multiply-accumulate instructions.

1During normal exception processing, the PSTDDATA output is driven to a 0xC indicating the exception
processing state. The exception stack write operands, as well as the vector read and target address of the
exception handler may also be displayed.
Exception ProcessingPSTDDATA = 0xC,{0xB,destination},// stack frame
{0xB,destination},// stack frame
{0xB,source},// vector read
PSTDDATA = 0x5,{[0x9AB],target}// handler PC
The PSTDDATA specification for the reset exception is shown below:
Exception ProcessingPSTDDATA = 0xC,
PSTDDATA = 0x5,{[0x9AB],target}// handler PC
The initial references at address 0 and 4 are never captured nor displayed since these accesses are treated
as instruction fetches.
For all types of exception processing, the PSTDDATA = 0xC value is driven at all times, unless the PSTDDATA
output is needed for one of the optional marker values or for the taken branch indicator (0x5).
2For JMP and JSR instructions, the optional target instruction address is displayed only for those effective
address fields defining variant addressing modes. This includes the following <ea>x values: (An), (d16,An),
(d8,An,Xi), (d8,PC,Xi).
3For Move Multiple instructions (MOVEM), the processor automatically generates line-sized transfers if the
operand address reaches a 0-modulo-16 boundary and there are four or more registers to be transferred. For
these line-sized transfers, the operand data is never captured nor displayed, regardless of the CSR value.
The automatic line-sized burst transfers are provided to maximize performance during these sequential
memory access operations.

Table 8-31. PSTDDATA Values for User-Mode Multiply-Accumulate Instructions

Instruction Operand Syntax PSTDDATA
mac.l Ry,Rx PSTDDATA = 0x1
mac.l Ry,Rx,<ea>y,Rw,ACCx PSTDDATA = 0x1,{0xB, source operand}
mac.l Ry,Rx,ACCx PSTDDATA = 0x1
mac.l Ry,Rx,ea,Rw PSTDDATA = 0x1,{0xB, source operand}
mac.w Ry,Rx PSTDDATA = 0x1
mac.w Ry,Rx,<ea>y,Rw,ACCx PSTDDATA = 0x1,{0xB, source operand}
mac.w Ry,Rx,ACCx PSTDDATA = 0x1
mac.w Ry,Rx,ea,Rw PSTDDATA = 0x1,{0xB, source operand}
move.l {Ry,#<data>},ACCext01 PSTDDATA = 0x1
move.l {Ry,#<data>},ACCext23 PSTDDATA = 0x1
move.l {Ry,#<data>},ACCx PSTDDATA = 0x1
move.l {Ry,#<data>},MACSR PSTDDATA = 0x1
move.l {Ry,#<data>},MASK PSTDDATA = 0x1
move.l ACCext01,Rx PSTDDATA = 0x1
move.l ACCext23,Rx PSTDDATA = 0x1
move.l ACCy,ACCx PSTDDATA = 0x1