On-Chip Peripheral Components
C513AO
User’s Manual
6-46
05.99
6.4
SSC Interface
The C513AO microcontroller provides a Synchronous Serial Channel (SSC) unit. This interface is
compatible with the popular SPI serial bus interface. It can be used for simple I/O expansion via shift
registers, for connection with a variety of peripheral components (such as A/D converters,
EEPROMs etc.), or interconnection of several microcontrollers in a master/slave structure. The
SSC unit supports full-duplex or half-duplex operation and can run in Master Mode or Slave Mode.
Figure 6-27 shows the block diagram of the SSC. The central element of the SSC is an 8-bit shift
register. The input and the output of this shift register are each connected via a control logic to the
pin P1.3/SRI (SSC Receiver In) and P1.4/STO (SSC Transmitter Out). This shift register can be
written to (SFR STB) and can be read through the Receive Buffer Register SRB.
Figure 6-27
SSC Block Diagram
Clock Divider
Clock Selection
Receive Buffer Register
Int. Enable Reg.
Control Register
. . .
f
OSC
2
Shift Register
STB
SRB
Pin
Control
Logic
Pin
Pin
Pin
Pin
P1.2 / SCLK
P1.3 / SRI
P1.4 / STO
P1.5 / SLS
SCIEN
SSCCON
SCF
Status Register
Control Logic
Interrupt
Internal Bus
MCB02438
