HD6417641 RENESAS [Renesas Technology Corp], HD6417641 Datasheet - Page 105

• Manufacturer Part Number: HD6417641
• Manufacturer: RENESAS [Renesas Technology Corp]

The start and end addresses are specified in MS and ME, then the DMX or DMY bit is set to 1.
When the X/Y data transfer instruction set in DMX/DMY is executed, the address register
contents before update are compared with ME*
in the address register as the updated value*
specified for the X/Y data transfer instruction, the address pointer will not return to modulo start
address MS even though the address register contents match ME.
Notes: 1. Bits 1 to 15 of the address register are used for comparison. Though ME retains its
The maximum modulo size is 64-kbytes. This is sufficient to access the X and Y data memory. A
block diagram of modulo addressing is shown in figure 2.14.
ModAddr:
ModStart: .DATA
ModEnd:
+2
+0
31
2. The MS value is stored in bits 1 to 15 of the address register. Though MS retains its
R8[Ix]
previous value for bit 0, 0 must always be written to bit 0.
previous value for bit 0, 0 must always be written to bit 0.
MOV.L ModAddr,Rn;
LDC Rn,MOD;
.DATA.W
.DATA.W
.DATA
0
:
ALU
31
15
R4[Ax]
R5[Ax]
XAB
16 15
ABx
Figure 2.14 Modulo Addressing
0
1
Instruction (MOVX/MOVY)
2
DMX
. If non-update address register addressing is
Rn=ModEnd, ModStart
ME=ModEnd, MS=ModStart
mEnd;
mStart;
15
15
CONT
CMP
1
MS
ME
. If they match, modulo start address MS is stored
DMY
1
1
ModEnd
ModStart
15
31
Rev. 4.00 Sep. 14, 2005 Page 55 of 982
R6[Ay]
R7[Ay]
16 15
ABy
YAB
1
0
AU
31
REJ09B0023-0400
R9[Iy]
Section 2 CPU
+2
+0
0