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FUJITSU MB91460 SERIES FR60 User Manual

Page 639

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623

Chapter 32 USART (LIN / FIFO)

4.USART Registers

* see table

4-3

for R/W options

Table 4-2 Functions of each bit of control register 04 (SCR04)

Bit name

Function

bit15

PEN: Parity enable
bit

This bit selects whether to add a parity bit during transmission in
serial asynchronous mode or detect it during reception.
Parity is only provided in mode 0 and in mode 2 if SSM of the
ECCR04 is selected. This bit is fixed to 0 (no parity) in mode 3
(LIN).

bit14

P: Parity selection bit

When parity is provided and enabled this bit selects even (0) or
odd (1) parity

bit13

SBL: Stop bit length
selection bit

This bit selects the length of the stop bit of an asynchronous data
frame or a synchronous frame if SSM of the ECCR04 is selected.
This bit is fixed to 0 (1 stop bit) in mode 3 (LIN).

bit12

CL: Data length
selection bit

This bit specifies the length of transmission or reception data. This
bit is fixed to 1 (8 bits) in mode 2 and 3.

bit11

AD: Address/Data
selection bit *

This bit specifies the data format in multiprocessor mode 1. Writing
to this bit determines an address or data frame to be sent next,
reading from it returns the last received kind of frame. “1” indicates
an address frame, “0” indicates a usual data frame.
Note:

During a RMW-Read cycle the AD bit returns the value to be
sent instead of the last received AD bit.
see table below*

bit10

CRE: Clear reception
error flags bit

This bit clears the FRE, ORE, and PE flag of the Serial Status
Register (SSR04). This bit also clears a possible reception
interrupt caused by errors.
Writing a 1 to it clears the error flag.
Writing a 0 has no effect.
Reading from it always returns 0.

bit9

RXE: Reception
enable bit

This bit enables USART reception.
If this bit is set to 0, USART disables the reception of data frames.
The LIN break detection in mode 0 or 3 remains unaffected.

bit8

TXE: Transmission
enable bit

This bit enables USART transmission. If this bit is set to 0, USART
disables the transmission of data frames.

Table 4-3 * Read/Write options of AD-Bit

Cycle

Action

Write

Write data to be sent to AD-Bit

Normal Read

Read received AD-Bit

RMW-Read

Read data to be sent from AD-Bit