15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
VCLK
SPICLK
SIMO[7]
SIMO[6]
SIMO[5]
SIMO[4]
SIMO[3]
SIMO[2]
SIMO[1]
SIMO[0]
SOMI[7]
SOMI[6]
SOMI[5]
SOMI[4]
SOMI[3]
SOMI[2]
SOMI[1]
SOMI[0]
Basic Operation
1526
SPNU563A – March 2018
Copyright © 2018, Texas Instruments Incorporated
Multi-Buffered Serial Peripheral Interface Module (MibSPI) with Parallel Pin
Option (MibSPIP)
Figure 28-29. 8 Pins Parallel Mode Timing Diagram (Phase 0, Polarity 0)
NOTE:
Modulo Count Parallel Mode is not supported in this device.
28.2.6.7 MibSPI Slave in Multi-buffer Configuration
When operating in slave mode, the MibSPI uses the chip-select pins 0 to 3 to generate a trigger to the
corresponding Transfer Group. For example, putting 0000 on the chip-select pins triggers Transfer Groups
0 and putting 0001 triggers TG1. When the value 1111 is set to the chip-select, the MibSPI is deselected,
that is Transfer Group 15 is not available in slave mode. The remaining chip-select pins should stay in
GPIO mode. In slave mode, the fields like trigger source and trigger event are not taken into account by
the sequencer. Only the SPICS pins can trigger a Transfer Group. The chip-select trigger operates as a
level-sensitive trigger. However, when the MibSPI is in 3-pin or 4-pin with SPIENA mode, just one
Transfer Group can be triggered and it is restricted to Transfer Group 0 (TG0). In slave mode, the PRST
field should be cleared to 0. If the corresponding Transfer Group is enabled, the multi-buffer reads the
current buffer of the TG and writes it into SPIDAT1. If Transfer Group is disabled, the multi-buffer does not
update the SPIDAT1 register.
NOTE:
If the selected Transfer Group is disabled and no update of the SPIDAT1 register has been
done, the data to be transferred is meaningless. Even the received data will not be copied to
the multi-buffer RAM. However it will be available on SPIBUF register until it is overwritten by
the subsequent receive data.