16-Bit Timer (2 Pins); Synchronous Serial Interfaces (Ssi0 And Ssi1) (10 Pins) - Motorola DSP56156 Manual

is asserted. In this case, all other HI control pins are ignored and the HI state is
not affected. HACK may be programmed as a general purpose I/O pin called
PB14 when the HI is not being used.
Note: HACK should always be pulled high when it is not in use.
2.7

16-BIT TIMER (2 PINS)

TIN (Timer input) - This input receives external pulses to be counted by the on-chip
16-bit timer when external clocking is selected. The pulses are internally syn-
chronized to the DSP core internal clock. TIN may be programmed as a general
purpose I/O pin called PC10 when the external event function is not being used.
TOUT (Timer output) - This output generates pulses or toggles on a timer overflow
event or a compare event. TOUT may be programmed as a general purpose
I/O pin called PC11 when disabled by the timer out enable bits (TO2-TO0).
2.8

SYNCHRONOUS SERIAL INTERFACES (SSI0 AND SSI1) (10 PINS)

(SSI0 Transmit Data) - This output pin transmits serial data from the SSI0
STD0
Transmit Shift Register. STD0 may be programmed as a general purpose I/O
pin called PC0 when the SSI0 STD0 function is not being used.
SRD0 (SSI0 Receive Data) - This input pin receives serial data and transfers the data
to the SSI0 Receive Shift Register. SRD0 may be programmed as a general
purpose I/O pin called PC1 when the SSI0 SRD0 function is not being used.
(SSI0 Serial Clock) - This bidirectional pin provides the serial bit rate clock for
SCK0
the SSI0 interface. SCK0 may be programmed as a general purpose I/O pin
called PC2 when the SSI0 interface is not being used.
SC10 (Serial Control 1) - This bidirectional pin is used by the SSI0 serial interface as
frame sync I/O or flag I/O. SC10 may be programmed as a general purpose I/O
pin called PC3 when the SSI0 is not using this pin.
(Serial Control 0) - This bidirectional pin is used by the SSI0 serial interface as
SC00
frame sync I/O or flag I/O. SC00 may be programmed as a general purpose I/O
pin called PC4 when the SSI0 is not using this pin.
STD1 (SSI1 Transmit Data) - This output pin transmits serial data from the SSI1
Transmit Shift Register. STD1 may be programmed as a general purpose I/O
pin called PC5 when the SSI1 STD1 function is not being used.
2 - 12
16-BIT TIMER (2 PINS)
DSP56156 PIN DESCRIPTIONS MOTOROLA