MPC5604B/C Microcontroller Reference Manual, Rev. 8
596 Freescale Semiconductor
Figure 25-3. Injected sample/conversion sequence
The injected conversion can be started using two options:
• By software setting the MCR[JSTART]; the current conversion is suspended and the injected chain
is converted. At the end of the chain, the JSTART bit in the MSR is reset and the normal chain
conversion is resumed.
• By an internal trigger signal from the PIT when MCR[JTRGEN] is set; a programmed event
(rising/falling edge depending on MCR[JEDGE]) on the signal coming from PIT starts the injected
conversion by setting the MSR[JSTART]. At the end of the chain, the MSR[JSTART] is cleared
and the normal conversion chain is resumed.
The MSR[JSTART] is automatically set when the Injected conversion starts. At the same time the
MCR[JSTART] is reset, allowing the software to program a new start of conversion. In that case the new
requested conversion starts after the running injected conversion is completed.
At the end of each injected conversion, an End Of Injected Conversion (JEOC) interrupt is issued (if
enabled by the IMR[MSKJEOC]) and at the end of the sequence an End Of Injected Chain (JECH)
interrupt is issued (if enabled by the IMR[MSKJEOC]).
If the content of all the injected conversion mask registers (JCMR) is zero (that is, no channel is selected)
the JECH interrupt is immediately issued after the start of conversion.
25.3.1.5 Abort conversion
Two different abort functions are provided.
• The user can abort the ongoing conversion by setting the MCR[ABORT] bit. The current
conversion is aborted and the conversion of the next channel of the chain is immediately started.
In the case of an abort operation, the NSTART/JSTART bit remains set and the ABORT bit is reset
after the conversion of the next channel starts. The EOC interrupt corresponding to the aborted
channel is not generated. This behavior is true for normal or Injected conversion modes. If the last
channel of a chain is aborted, the end of chain is reported generating an ECH interrupt.
• It is also possible to abort the current chain conversion by setting the MCR[ABORTCHAIN] bit.
In that case the behavior of the ADC depends on the MODE bit. If scan mode is disabled, the
NSTART bit is automatically reset together with the MCR[ABORTCHAIN] bit. Otherwise, if the
The ongoing channel conversion is interrupted and the injected
conversion chain is processed first. After the injected chain is
converted the normal chain conversion resumes from the channel at
which normal conversion was aborted.
Injected conversion of channels I and J
Normal conversion resumes from
the last aborted channel.
Sample B Convert B Sample C Sample D Convert D Sample E Convert EConvert C
Sample C Abort C Sample I Sample J Convert J Sample C Convert CConvert I
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