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MCF5307 User’s Manual
Background Debug Mode (BDM)
5.5.3.3.3 Read Memory Location (READ)
Read data at the longword address. Address space is dened by BAAR[TT,TM]. Hardware
forces low-order address bits to zeros for word and longword accesses to ensure that word
addresses are word-aligned and longword addresses are longword-aligned.
Command/Result Formats:
Command Sequence:
Figure 5-23. READ Command Sequence
Operand Data
The only operand is the longword address of the requested location.
Result Data
Word results return 16 bits of data; longword results return 32. Bytes
are returned in the LSB of a word result, the upper byte is undened.
0x0001 (S = 1) is returned if a bus error occurs.
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
Byte
Command
0x1
0x9
0x0
A[31:16]
A[15:0]
Result
XXXXXXXX
D[7:0]
Word
Command
0x1
0x9
0x4
0x0
A[31:16]
A[15:0]
Result
D[15:0]
Longword Command
0x1
0x9
0x8
0x0
A[31:16]
A[15:0]
Result
D[31:16]
D[15:0]
Figure 5-22. READ Command/Result Formats
MS ADDR
"NOT READY"
LS ADDR
"NOT READY"
READ (B/W)
???
NEXT CMD
"NOT READY"
XXX
"NOT READY"
XXX
BERR
RESULT
NEXT CMD
READ
MEMORY
LOCATION
MS ADDR
"NOT READY"
LS ADDR
"NOT READY"
READ (LONG)
???
NEXT CMD
"NOT READY"
XXX
"NOT READY"
XXX
BERR
MS RESULT
XXX
READ
MEMORY
LOCATION
NEXT CMD
LS RESULT
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