Slave Select Input Operation - Infineon Technologies TC1728 User Manual

18.1.2.8 Slave Select Input Operation

For systems with multiple slaves, the SSC module provides seven SLSI slave select
input lines, that permit enabling or disabling of the SCLK, MTSR, and MRST signals in
Slave Mode. Slave Mode is selected by CON.MS = 0. The SLSI input logic shown in
Figure 18-8 is controlled by register PISEL and CON.
Note: In the following description, only one of the seven SLSI input lines is mentioned.
The remaining six SLSI input lines are connected to the other six inputs of the input
multiplexer, which is controlled by PISEL.SLSIS.
To/From
Internal
Control
SSC Kernel
Slave Mode
Figure 18-8 Slave Select Input Logic
With PISEL.SLSIS = 000
the SSC I/O lines. The slave receive input signal MTSRA or MTSRB (selected by
PISEL.SRIS) and the slave clock input signal SCLKA or SCLKB (selected by
PISEL.SCIS) are passed further as MTRSI and SCLKI to the internal SSC control logic.
The slave transmit signal MRSTI from the internal SSC control logic MRSTI is passed
directly to MRST.
With PISEL.SLSIS = 001
as a slave select signal as follows:
• SLSI = 1: SSC slave is not selected.
– The slave receive input signals, MTSRA or MTSRB are connected to MTSRI,
depending on PISEL.SRIS (Slave Mode receive input select).
User's Manual
SSC, V1.41 2010-06
MTSRI
MRSTI
PISEL.STIP
SCLKI
and Slave Mode selected, the SLSI input line does not control
B
, input signal SLSI controls the operation of the SSC I/O lines
B
Synchronous Serial Interface (SSC)
PISEL.SRIS
0
1
PISEL.SCIS
0
CON.PO
1
0
000
001
PISEL.SLSIS
18-16
MTSRA
0
MTSRB
1
MRST
Control
SCLKA
0
SCLKB
1
SLSI
MCA06219
TC1728
Port
V1.0, 2011-12