Chapter 10 Analog-to-Digital Converter (ADC12B_LBA_V1)
S12ZVHY/S12ZVHL Family Reference Manual Rev. 1.05
Freescale Semiconductor
405
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Function:
Start the first conversion of a conversion sequence which is defined in the active Command
Sequence List
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Requested by:
- Positive edge of internal interface signal Trigger
- Write Access via data bus to set control bit TRIG
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When finished:
This bit is cleared by the ADC when the first conversion of the sequence is beginning to
sample
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Mandatory Requirements:
- In all ADC conversion flow control modes bit TRIG is only set (Trigger Event executed)
if the Trigger Event occurs while no conversion or conversion sequence is ongoing (ADC
idle)
- In ADC conversion flow control mode “Restart Mode” with a Restart Event in progress it
is not allowed that a Trigger Event occurs before the background command load phase has
finished (Restart Event has been executed) else the error flag TRIG_EIF is set
- In ADC conversion flow control mode “Trigger Mode” a Restart Event causes bit TRIG
being set automatically. Bit TRIG is set when no conversion or conversion sequence is
ongoing (ADC idle) and the RVL done condition is reached by one of the following:
* A “End Of List” command type has been executed
* A Sequence Abort Event is in progress or has been executed
The ADC executes the Restart Event followed by the Trigger Event.
- In ADC conversion flow control mode “Trigger Mode” a Restart Event and a simultaneous
Trigger Event via internal interface or data bus causes the TRIG_EIF bit being set and ADC
cease operation.
•
Restart Event
(with current active CSL)
Internal Interface Signal: Restart
Corresponding Bit Name: RSTA
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Function:
- Go to top of active CSL (clear index register for CSL)
- Load one background command register and wait for Trigger (CSL offset register is not
switched independent of bit CSL_BMOD)
- Set error flag RSTA_EIF when a Restart Request occurs before one of the following
conditions was reached:
* The "End Of List" command type has been executed
* Depending on bit STR_SEQA if the "End Of List" command type is about to be executed
* The current CSL has been aborted or is about to be aborted due to a Sequence Abort
Request.
–
Requested by:
- Positive edge of internal interface signal Restart
- Write Access via data bus to set control bit RSTA
