PXD10RM Datasheet, PDF (972/1332 Pages) Freescale Semiconductor, Inc – PXD10 Microcontroller

26.6.2.5 Read/Write Access Control/Status (RWCS)
The read write access control/status register provides control for read/write access. Read/write access
provides DMA-like access to memory-mapped resources on the system bus while the processor is halted
or during runtime. The RWCS register also provides read/write access status information as shown in
Table 26-9.
Nexus 0x0007
Reg:
0
1
2
3
4
R _{AC RW}
SZ
W
Reset ₀
0
0
0
0
5
6
7
MAP
0
0
0
Access: User read/write
8
9
PR
10 11 12 13 14 15
0
0
0
0
0
0
0
0
0
0
0
0
0
0
16
R
W
Reset ₀
17 18 19 20 21 22 23 24 25 26 27 28 29
CNT
0
0
0
0
0
0
0
0
0
0
0
0
0
Figure 26-8. Read/Write Access Control/Status Register (RWCS)
30 31
ERR DV
0
0
Table 26-8. RWCS Field Description
Field
Description
0
Access Control.
AC 0 End access.
1 Start access.
1
Read/Write Select.
RW 0 Read access.
1 Write access.
2–4
SZ[2:0]
Word Size.
000 8-bit (byte.)
001 16-bit (halfword).
010 32-bit (word).
011 64-bit (doubleword—only in burst mode).
100–111 Reserved (default to word).
5–7 MAP Select.
MAP[2:0] 000 Primary memory map.
001-111 Reserved.
8–9
PR[1:0]
Read/Write Access Priority.
00 Lowest access priority.
01 Reserved (default to lowest priority).
10 Reserved (default to lowest priority).
11 Highest access priority.
10–15 Reserved.
26-12
PXD10 Microcontroller Reference Manual, Rev. 1
Preliminary—Subject to Change Without Notice
Freescale Semiconductor