Motorola DSP56301 user manual Enhanced Serial Synchronous Interface, PD0, PD1, PD2

Models: DSP56301

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Enhanced Synchronous Serial Interface 1

2.9Enhanced Synchronous Serial Interface 1

Table 2-14.Enhanced Serial Synchronous Interface 1

Signal Name

Type

State During

Signal Description

Reset

 

 

 

 

 

 

 

 

 

 

 

SC10

Input or Output

Input

Serial Control 0—For asynchronous mode, this signal is

 

 

 

used for the receive clock I/O (Schmitt-trigger input). For

 

 

 

synchronous mode, this signal is used either for transmitter 1

 

 

 

output or for serial I/O flag 0.

 

 

 

Port D 0—The default configuration following reset is GPIO

 

 

 

input PD0. When configured as PD0, signal direction is

 

Input or Output

 

controlled through the port directions register (PRR1). The

PD0

 

 

signal can be configured as an ESSI signal SC10 through the

 

 

 

port control register (PCR1).

 

 

 

This signal has a weak keeper to maintain the last state even

 

 

 

if all drivers are tri-stated.

 

 

 

 

SC11

Input/

Input

Serial Control 1—For asynchronous mode, this signal is the

 

Output

 

receiver frame sync I/O. For synchronous mode, this signal is

 

 

 

used either for Transmitter 2 output or for Serial I/O Flag 1.

 

 

 

Port D 1—The default configuration following reset is GPIO

 

 

 

input PD1. When configured as PD1, signal direction is

 

 

 

controlled through PRR1. The signal can be configured as an

 

 

 

ESSI signal SC11 through PCR1.

PD1

Input or Output

 

 

 

 

 

This signal has a weak keeper to maintain the last state even

 

 

 

if all drivers are tri-stated.

 

 

 

 

SC12

Input/

Input

Serial Control Signal 2—For frame sync I/O. SC12 is the

 

Output

 

frame sync for both the transmitter and receiver in

 

 

 

synchronous mode, and for the transmitter only in

 

 

 

asynchronous mode. When configured as an output, this

 

 

 

signal is the internally generated frame sync signal. When

 

 

 

configured as an input, this signal receives an external frame

 

 

 

sync signal for the transmitter (and the receiver in

 

 

 

synchronous operation).

 

 

 

Port D 2—The default configuration following reset is GPIO

PD2

Input or Output

 

input PD2. When configured as PD2, signal direction is

 

 

 

controlled through PRR1. The signal can be configured as an

 

 

 

ESSI signal SC12 through PCR1.

 

 

 

This signal has a weak keeper to maintain the last state even

 

 

 

if all drivers are tri-stated.

 

 

 

 

Signals/Connections

2-25

Page 55
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Motorola DSP56301 user manual Enhanced Serial Synchronous Interface, PD0, PD1, PD2