Conversion Command Word Table (Ccw); Qadc Status Register 1 (Qasr1); Qasr1 Field Descriptions - Motorola ColdFire MCF5281 User Manual

Motorola microcontroller user's manual
Table of Contents

Advertisement

Register Descriptions

27.6.6.2 QADC Status Register 1 (QASR1)

Stop mode resets this register .
15
Field
Reset
R/W:
7
Field
Reset
R/W:
Address
Bit(s)
Name
15–14
13–8
CWPQ1
7–6
5–0
CWPQ

27.6.7 Conversion Command Word Table (CCW)

The CCW table is 64 half-word (128 byte) long RAM with 10 bits of each entry
implemented. The CCW table is written by the user and is not modified by the QADC. Each
CCW requests the conversion of one analog channel to a digital result. The CCW specifies
the analog channel number, the input sample time, and whether the queue is to pause after
27-26
14
13
CWPQ15
CWPQ14
6
5
CWPQ25
CWPQ24
IPSBAR + 0x19_0012, 0x19_0013
Figure 27-13. QADC Status Register 1 (QASR1)
Table 27-13. QASR1 Field Descriptions
Reserved, should be cleared.
Queue 1 command word pointer. Points to the last queue 1 CCW executed. This is a read-only
field with a valid range of 0 to 63; writes have no effect. CWPQ1 always points to the last
executed CCW in queue 1, regardless of which queue is active.
In contrast to CWP, CPWQ1 is updated when a conversion result is written. When the QADC
finishes a conversion in queue 1, both the result register is written and CWPQ1 is updated.
When queue 1 operation is terminated after a CCW is read that is pointed to by BQ2, CWP
points to BQ2 while CWPQ1 points to the last queue 1 CCW.
During stop mode, CWPQ1 is reset to 63, because the control registers and the analog logic are
reset. When debug mode is entered, CWPQ1 is not changed; it points to the last executed CCW
in queue 1.
Reserved, should be cleared.
Queue 2 command word pointer. Points to the last queue 2 CCW executed. This is a read-only
field with a valid range of 0 to 63; writes have no effect. CWPQ2 always points to the last
executed CCW in queue 2, regardless which queue is active.
In contrast to CWP, CPWQ2 is updated when a conversion result is written. When the QADC
finishes a conversion in queue 2, both the result register is written and CWPQ2 is updated.
During stop mode, CWPQ2 is reset to 63 because the control registers and the analog logic are
reset. When debug mode is entered, CWPQ2 is not changed; it points to the last executed CCW
in queue 2.
MCF5282 User's Manual
12
11
10
CWPQ13
CWPQ12
0011_1111
R
4
3
CWPQ23
CWPQ22
0011_1111
R
Description
9
8
CWPQ11
CWPQ10
2
1
0
CWPQ21
CWPQ20
MOTOROLA

Advertisement

Table of Contents
loading

This manual is also suitable for:

Coldfire mcf5282

Table of Contents