MOTOROLA
Chapter 27. Queued Analog-to-Digital Converter (QADC)
27-39
Digital Control Subsystem
The choice of single-scan or continuous-scan applies to the full queue, and is not applied to
each subqueue. Once a subqueue is initiated, each CCW is executed sequentially until the
last CCW in the subqueue is executed and the pause state is entered. Execution can only
continue with the next CCW, which is the beginning of the next subqueue. A subqueue
cannot be executed a second time before the overall queue execution has been completed.
Figure 27-22. QADC Queue Operation with Pause
Trigger events which occur during the execution of a subqueue are ignored, but the trigger
overrun flag is set. When a continuous-scan mode is selected, a trigger event occurring after
the completion of the last subqueue (after the queue completion flag is set), causes the
execution to continue with the first subqueue, starting with the first CCW in the queue.
When the QADC encounters a CCW with the pause bit set, the queue enters the paused state
after completing the conversion specified in the CCW with the pause bit. The pause flag is
set in QASR0, and a pause interrupt may be requested. The status of the queue is shown to
be paused, indicating completion of a subqueue. The QADC then waits for another trigger
event to again begin execution of the next subqueue.
Beginning of Queue 1
00
Channel Select,
Sample, Hold,
A/D Conversion
Conversion Command
Result Word Table
0
Pause
Word (CCW) Table
0
0
1
0
0
0
1
0
Pause
00
P
0
Pause
0
0
1
0
1
0
1
0
Pause
P
End of Queue 1
Beginning of Queue 2
BQ2
Pause
Pause
End of Queue 2
P
1
0
63
63
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Summary of Contents for ColdFire MCF5281
Page 124: ...3 20 MCF5282 User s Manual MOTOROLA EMAC Instruction Set Summary ...
Page 141: ...MOTOROLA Chapter 5 Static RAM SRAM 5 5 SRAM Programming Model ...
Page 142: ...5 6 MCF5282 User s Manual MOTOROLA SRAM Programming Model ...
Page 168: ...6 26 MCF5282 User s Manual MOTOROLA Interrupts ...
Page 186: ...7 18 MCF5282 User s Manual MOTOROLA Functional Description ...
Page 228: ...9 22 MCF5282 User s Manual MOTOROLA Functional Description ...
Page 246: ...10 18 MCF5282 User s Manual MOTOROLA Low Power Wakeup Operation ...
Page 254: ...11 8 MCF5282 User s Manual MOTOROLA Memory Map and Registers ...
Page 264: ...12 10 MCF5282 User s Manual MOTOROLA Chip Select Registers ...
Page 280: ...13 16 MCF5282 User s Manual MOTOROLA Misaligned Operands ...
Page 314: ...14 34 MCF5282 User s Manual MOTOROLA MCF5282 External Signals ...
Page 339: ...MOTOROLA Chapter 15 Synchronous DRAM Controller Module 15 25 SDRAM Example ...
Page 340: ...15 26 MCF5282 User s Manual MOTOROLA SDRAM Example ...
Page 356: ...16 16 MCF5282 User s Manual MOTOROLA DMA Controller Module Functional Description ...
Page 408: ...17 52 MCF5282 User s Manual MOTOROLA Buffer Descriptors ...
Page 446: ...20 24 MCF5282 User s Manual MOTOROLA Interrupts ...
Page 474: ...22 18 MCF5282 User s Manual MOTOROLA Programming Model ...
Page 510: ...23 36 MCF5282 User s Manual MOTOROLA Operation ...
Page 526: ...24 16 MCF5282 User s Manual MOTOROLA I2C Programming Examples ...
Page 672: ...28 12 MCF5282 User s Manual MOTOROLA Functional Description ...
Page 718: ...29 46 MCF5282 User s Manual MOTOROLA Motorola Recommended BDM Pinout ...
Page 750: ...32 8 MCF5282 User s Manual MOTOROLA Ordering Information ...