Section 4.2 – Texas Instruments TMS320DM646X DMSOC User Manual
Page 50

Registers
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4.2
Asynchronous Wait Cycle Configuration Register (AWCCR)
The asynchronous wait cycle configuration register (AWCCR) is used to configure the parameters for
extended wait cycles. Both the polarity of the EM_WAIT[5:2] pins and the maximum allowable number of
extended wait cycles can be configured. the AWCCR is shown in
and described in
.
NOTE:
The EW bit in the asynchronous configuration register (ACFGn) must be set to allow for the
insertion of extended wait cycles.
Figure 21. Asynchronous Wait Cycle Configuration Register (AWCCR)
31
30
29
28
27
24
23
22
21
20
19
18
17
16
WP3
WP2
WP1
WP0
Reserved
CS5_WAIT
CS4_WAIT
CS3_WAIT
CS2_WAIT
R/W-1
R/W-1
R/W-1
R/W-1
R-0
R/W-3h
R/W-2h
R/W-1
R/W-0
15
8
7
0
Reserved
MEWC
R-0
R/W-80h
LEGEND: R/W = Read/Write; R = Read only; -n = value after reset
Table 34. Asynchronous Wait Cycle Configuration Register (AWCCR) Field Descriptions
Bit
Field
Value
Description
31
WP3
WAIT polarity bit. This bit defines the polarity of the EM_WAIT[5] pin.
0
Insert wait cycles if EM_WAIT[5] pin is low.
1
Insert wait cycles if EM_WAIT[5] pin is high.
30
WP2
WAIT polarity bit. This bit defines the polarity of the EM_WAIT[4] pin.
0
Insert wait cycles if EM_WAIT[4] pin is low.
1
Insert wait cycles if EM_WAIT[4] pin is high.
29
WP1
WAIT polarity bit. This bit defines the polarity of the EM_WAIT[3] pin.
0
Insert wait cycles if EM_WAIT[3] pin is low.
1
Insert wait cycles if EM_WAIT[3] pin is high.
28
WP0
WAIT polarity bit. This bit defines the polarity of the EM_WAIT[2] pin.
0
Insert wait cycles if EM_WAIT[2] pin is low.
1
Insert wait cycles if EM_WAIT[2] pin is high.
27-24
Reserved
0
Reserved
23-22
CS5_WAIT
0-3h
EM_WAIT[5:2] pin map for chip select 5. By default, the EM_WAIT[5] pin is used for chip select 5.
0
EM_WAIT[2] pin is used.
1h
EM_WAIT[3] pin is used.
2h
EM_WAIT[4] pin is used.
3h
EM_WAIT[5] pin is used.
21-20
CS4_WAIT
0-3h
EM_WAIT[5:2] pin map for chip select 4. By default, the EM_WAIT[4] pin is used for chip select 4.
0
EM_WAIT[2] pin is used.
1h
EM_WAIT[3] pin is used.
2h
EM_WAIT[4] pin is used.
3h
EM_WAIT[5] pin is used.
19-18
CS3_WAIT
0-3h
EM_WAIT[5:2] pin map for chip select 3. By default, the EM_WAIT[3] pin is used for chip select 3.
0
EM_WAIT[2] pin is used.
1h
EM_WAIT[3] pin is used.
2h
EM_WAIT[4] pin is used.
3h
EM_WAIT[5] pin is used.
50
Asynchronous External Memory Interface (EMIF)
SPRUEQ7C – February 2010
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