MMC2107 Datasheet, PDF (482/618 Pages) –

Freescale Semiconductor, Inc.
Queued Analog-to-Digital Converter (QADC)
Technical Data
482
CONVERSION COMMAND
WORD (CCW) TABLE
00
BEGINNING OF QUEUE 1
RESULT WORD TABLE
00
•
•
•
•
•
•
END OF QUEUE 1
BEGINNING OF QUEUE 2
CHANNEL SELECT,
SAMPLE, HOLD,
A/D CONVERSION
•
•
•
63
END OF QUEUE 2
•
•
•
63
10-BIT CONVERSION COMMAND
WORD FORMAT
98
[7:6]
[5:0]
P BYP IST
CHAN
P — PAUSE AFTER CONVERSION
UNTIL NEXT TRIGGER
BYP — BYPASS BUFFER AMPLIFIER
IST — INPUT SAMPLE TIME
CHAN — CHANNEL NUMBER AND
END-OF-QUEUE CODE
10-BIT RESULT, READABLE IN
THREE 16-BIT FORMATS
15 14 13 12 11 10
[9:0]
000000
RESULT
RIGHT-JUSTIFIED, UNSIGNED RESULT
[15:6]
[5:0]
S
RESULT
000000
LEFT-JUSTIFIED, SIGNED RESULT
[15:6]
[5:0]
RESULT
000000
LEFT-JUSTIFIED, UNSIGNED RESULT
Figure 18-44. QADC Conversion Queue Operation
To prepare the QADC for a scan sequence, the software writes to the
CCW table to specify the desired channel conversions. The software
also establishes the criteria for initiating the queue execution by
programming the queue operating mode. The queue operating mode
determines what type of trigger event causes queue execution to begin.
A trigger event refers to any of the ways to cause the QADC to begin
executing the CCWs in a queue or subqueue. An external trigger is only
one of the possible trigger events.
A scan sequence may be initiated by:
• A software command
• Expiration of the periodic/interval timer
• External trigger signal
• External gated signal (queue 1 only)
Queued Analog-to-Digital Converter (QADC)
For More Information On This Product,
Go to: www.freescale.com
MMC2107 – Rev. 2.0
MOTOROLA