User Manual
665
Rev. 1.1
2019-03-18
TLE984xQX
Microcontroller with LIN and Power Switches for Automotive Applications
High-Speed Synchronous Serial Interface SSC1/SSC2
Note:
Of course, this can happen only in multiples of the selected basic data width, because it would
require disabling/enabling of the SSC to reprogram the basic data width on-the-fly.
21.3.5.1 Port Control
The SSC uses three lines to communicate with the external world. Pin SCLK serves as the clock line, while pins
MRST (Master Receive/Slave Transmit) and MTSR (Master Transmit/Slave Receive) serve as the serial data
input/output lines. As shown in
these three lines (SCLK as input, Master Receive, Slave Receive)
have all two inputs at the SSC Module kernel. Three bits in register PISEL define which of the two kernel inputs
(A or B) are connected. This feature allows for each of the three SSC communication lines to be connected to
two inputs coming from different port pins.
Operation of the SSC I/O lines depends on the selected operating mode (master or slave). The direction of the
port lines depends on the operating mode. The SSC will automatically use the correct kernel output or kernel
input line of the ports when switching modes. Port pins assigned as SSC I/O lines can be controlled in two
ways:
• By hardware
• By software
When the SSC I/O lines are connected with dedicated pins typically hardware I/O control should be used. In
this case, the two output signals reflect directly the state of the CON.EN and CON.MS bits (the M/S select line
is inverted to the CON.MS bit definition).
When the SSC I/O lines are connected with bidirectional lines of general purpose I/O ports, typically software
I/O control should be used. In this case port registers must be programmed for alternate output and input
selection. When switching between master and slave mode, port registers must be reprogrammed.