Motorola ColdFire MCF5281 User Manual
Page 558
Queued Analog-to-Digital Converter (QADC)
28-20
Freescale Semiconductor
7
6
5
4
3
2
1
0
Field
QS7
QS6
CWP5
CWP4
CWP3
CWP2
CWP1
CWP0
Reset
0000_0000
R/W:
R
Address
IPSBAR + 0x19_0010, 0x19_0011
Figure 28-11. QADC Status Register 0 (QASR0)
Table 28-10. QASR0 Field Descriptions
Bit(s)
Name
Description
15, 13
CFn
Queue completion flag. Indicates that a queue scan has been completed. CF[1:2] is
set by the QADC when the input channel sample requested by the last CCW in the
queue is converted, and the result is stored in the result table.
When CFn is set and queue completion interrupts are enabled (QACRn[CIEn] = 1),
the QADC requests an interrupt. The interrupt request is cleared when a 0 is written
to the CF1 bit after it has been read as a 1. Once set, CF1 can be cleared only by a
reset or by writing a 0 to it.
CF[1:2] is updated by the QADC regardless of whether the corresponding interrupt is
enabled. This allows polled recognition of the queue scan completion.
14, 12
PFn
Queue pause flag. Indicates that a queue scan has reached a pause. PF[1:2] is set by
the QADC when the current queue 1 CCW has the pause bit set, the selected input
channel has been converted, and the result has been stored in the result table.
When PFn is set and interrupts are enabled (QACRn[PIEn] = 1), the QADC requests
an interrupt. The interrupt request is cleared when a 0 is written to PFn, after it has
been read as a 1. Once set, PFn can be cleared only by reset or by writing a 0 to it.
PF1:
1 Queue 1 has reached a pause or gate closed before end-of-queue in gated mode.
0 Queue 1 has not reached a pause or gate has not closed before end-of-queue in
gated mode.
PF2:
1 Queue 2 has reached a pause.
0 Queue 2 has not reached a pause.
See
for a summary of CCW pause bit response in all scan modes.
11–10
TORn
Queue trigger overrun flag. Indicates that an unexpected trigger event has occurred
for queue 1. TOR[1:2] can be set only while the queue is in the active state.
Once set, TOR[1:2] is cleared only by a reset or by writing a 0 to it.
1 At least one unexpected queue 1 trigger event has occurred or queue 1 reaches an
end-of-queue condition for the second time in externally gated continuous scan.
0 No unexpected queue 1 trigger events have occurred.
MCF5282 and MCF5216 ColdFire Microcontroller User’s Manual, Rev. 3