PXD20RM Datasheet, PDF (148/1628 Pages) Freescale Semiconductor, Inc – PXD20 Microcontroller

Table 5-3. Main Configuration Register (MCR) field descriptions
Bit
Description
0
OWREN: Overwrite enable
This bit enables or disables the functionality to overwrite unread converted data.
0 Prevents overwrite of unread converted data; new result is discarded.
1 Enables converted data to be overwritten by a new conversion.
1
WLSIDE: Write left/right-aligned
0 The conversion data is written right-aligned.
1 Data is left-aligned (from 15 to (15 – resolution + 1)).
2
MODE: One Shot/Scan
0 One Shot Mode—Configures the normal conversion of one chain.
1 Scan Mode—Configures continuous chain conversion mode; when the programmed chain
conversion is finished it restarts immediately.
3
EDGLEV: Edge or level selection for external start trigger
0 Edge configuration for external trigger usage.
1 Level configuration for external trigger usage.
4
TRGEN: External trigger enable. This bit must be set to use external triggering to start a conversion.
0 An external trigger cannot be used to start a conversion.
1 An external trigger can start a conversion.
5
Start trigger edge/ level detection. The following table shows the interaction between the EDGE bit and
the TRGEN and EDGLEV bits.
Table 0-1
TRGEN
0
1
1
1
EDGLEV
n
0
0
1
EDGE
n
0
1
0
Trigger Detection
External triggering disabled
External trigger on falling edge of trigger
External trigger on rising edge of trigger
External trigger on low edge of trigger
6
Reserved
Must be kept at 0.
7
NSTART: Normal Start conversion
Setting this bit starts the chain or scan conversion. Resetting this bit during scan mode causes the
current chain conversion to finish, then stops the operation.
This bit stays high while the conversion is ongoing (or pending during injection mode).
0 Causes the current chain conversion to finish and stops the operation.
1 Starts the chain or scan conversion.
8
Reserved
Write of any value has no effect, read value is always 0.
9
JTRGEN: Injection external trigger enable
0 External trigger disabled for channel injection (injected conversion cannot be started using an
external signal).
1 External trigger enabled for channel injection.
PXD20 Microcontroller Reference Manual, Rev. 1
5-6
Freescale Semiconductor
Preliminary—Subject to Change Without Notice