PXD20RM Datasheet, PDF (1124/1628 Pages) Freescale Semiconductor, Inc – PXD20 Microcontroller

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 30-8. Read/Write Access Control/Status Register (RWCS)
30 31
ERR DV
0
0
Table 30-8. 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.
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.
16–31 Access Control Count. Number of accesses of word size SZ.
CNT[13:0]
30
ERR
Read/Write Access Error. See Table 30-9.
31
Read/Write Access Data Valid. See Table 30-9.
DV
30-12
PXD20 Microcontroller Reference Manual, Rev. 1
Preliminary—Subject to Change Without Notice
Freescale Semiconductor