Control Registers
1198
SPNU503C – March 2018
Copyright © 2018, Texas Instruments Incorporated
Multi-Buffered Serial Peripheral Interface Module (MibSPI) with Parallel Pin
Option (MibSPIP)
Table 24-42. TG Control Registers (TGxCTRL) Field Descriptions (continued)
Bit
Field
Value
Description
27-24
Reserved
0
Reads return 0. Writes have no effect.
23-20
TRIGEVTx
Type of trigger event. A level-triggered TG can be stopped by de-activating the level trigger.
However, the following restrictions apply.
• Deactivating the level trigger for a TG during a NOBRK transfer does not stop the transfers until
all of the ICOUNT number of buffers are transferred for the NOBRK buffer. Once a NOBRK
buffer is prefetched, the trigger event loses control over the TG until the NOBRK buffer transfer
is completed.
• Once the transfer of a buffer with CSHOLD or LOCK bit set starts, deactivating the trigger level
does not stop the transfer until the sequencer completes the transfer of the next non-CSHOLD
or non-LOCK buffer in the same TG.
• Once the last buffer in a TG is pre-fetched, de-activating the trigger level does not stop the
transfer group until the last buffer transfer is completed. This means even if the trigger level is
deactivated at the beginning of the penultimate (one-before-last) buffer transfer, the sequencer
continues with the same TG until it is completed.
0
never
Never trigger TGx. This is the default value after reset.
1h
rising
edge
A rising edge (0 to 1) at the selected trigger source (TRIGSRCx) initiates a transfer for
TGx
2h
falling
edge
A falling edge (1 to 0) at the selected trigger source (TRIGSRCx) initiates a transfer for
TGx
3h
both
edges
Rising and falling edges at the selected trigger source (TRIGSRCx) initiates a transfer
for TGx
4h
Rsvd
Reserved
5h
high-
active
While the selected trigger source (TRIGSRCx) is at a logic-high level (1), the group
transfer is continued and at the end of one group, transfer is restarted at the beginning.
If the logic level changes to low (0) during an ongoing group transfer, the whole group
transfer will be stopped.
Note: If ONESHOTx is set, the transfer is performed only once.
6h
low-
active
While the selected trigger source (TRIGSRCx) is at a logic-low level (0), the group
transfer is continued and at the end of one group, transfer is restarted at the beginning.
If the logic level changes to high (1) during an ongoing group transfer, the whole group
transfer will be stopped.
Note: If ONESHOTx is set, the transfer is performed only once.
7h
always
A repetitive group transfer will be performed.
Note: By setting the TRIGSRC to 0, the TRIGEVT to 7h (ALWAYS), and the
ONESHOTx bit to 1, software can trigger this TG. Upon setting the TGENA bit, the
TG is immediately triggered.
Note: If ONESHOTx is set, the transfer is performed only once.
8h-Fh
Rsvd
Reserved