Fujitsu MB96300 series Hardware Manual page 140

CHAPTER 4 DMA
4.3.4 Buffer Address Pointer (BAP)
This section describes the Buffer Address Pointer (BAP).
■ Buffer Address Pointer (BAP)
The Buffer Address Pointer (BAP) is a 24-bit register and is used to store addresses that will be used for
DMA transfer. Any address can be specified.
When "Update Performed" is specified using the DMACS:BF bit, the BAP lower 16 bits (BAPM, BAPL) are
incremented by "1" at byte transfer and incremented by "2" at word transfer. Its upper 8 bits do not change.
When DMASC:BPD is set, BAP is decremented by "1" or "2" instead of incremented. When "Update Not
Performed" is specified with the DMACS:BF bit, BAP is fixed (BAP does not change).
Figure 4.3-5 "Buffer Address Pointer (BAP)" shows the configuration of the Buffer Address Pointer (BAP).
Address:
8*ch +
0x102
Read/Write:
Initial Value:
Address: 15 14
8*ch +
0x101, 0x100 B15 B14
Read/Write: (R/W) (R/W) (R/W) (R/W) (R/W) (R/W) (R/W) (R/W)
Initial Value: X X
R/W: readable and writable
Notes:
The area that can be specified using the I/O Register Address Pointer (IOA) is "000000
The area that can be specified using the Buffer Address Pointer (BAP) is "000000
The following addresses should not be specified for IOA and BAP: addresses of DMA controller internal
registers (DISEL0...15, DSR, DSSR, DER); addresses of DMA descriptors "000100
132
Figure 4.3-5 Buffer Address Pointer (BAP)
BAPM
13 12 11 10 09 08
B13 B12 B11 B10 B9 B8
X X X X X
MB96300 Super Series Hardware Manual
BAPH
07 06 05 04
B23 B22 B21 B20
(R/W) (R/W) (R/W) (R/W) (R/W) (R/W)
X X X X
BAPL
07 06 05 04
B7 B6 B5 B4
(R/W) (R/W) (R/W) (R/W) (R/W) (R/W)
X X X X X
03 02 01 00 Bit No.
B19 B18 B17 B16 BAP
(R/W) (R/W)
X X X X
03 02 01 00 Bit No.
B3 B2 B1 B0 BAP
(R/W) (R/W)
X X X X
" to "00FFFF
H
" to "FFFFFF
H
" to "00017F
H
".
H
".
H
".
H