Typewriter User Manual

MOTOROLA MC68340 USER’S MANUAL 7- 47
The following steps are channel specific:
Clock Select Register (CSR)
• Select the receiver and transmitter clock.
Mode Register 1 (MR1)
• If desired, program operation of receiver ready-to-send (RxRTS bit).
• Select receiver-ready or FIFO-full notification (R/F bit).
• Select character or block error mode (ERR bit).
• Select parity mode and type (PM and PT bits).
• Select number of bits per character (B/Cx bits).
Mode Register 2 (MR2)
• Select the mode of channel operation (CMx bits).
• If desired, program operation of transmitter ready-to-send (TxRTS bit).
• If desired, program operation of clear-to-send (TxCTS bit).
• Select stop-bit length (SBx bits).
Command Register (CR)
• Enable the receiver and transmitter.
7.5.2 Serial Module Example Configuration Code
The following code is an example of a configuration sequence for the serial module.
***************************************************************************
* MC68340 basic serial module register initialization example code.
* This code is used to initialize the 68340's internal serial module registers,
* providing basic functions for operation.
* It sets up serial channel A for communication with a 9600 baud terminal.
* Note: All serial module registers must be accessed as bytes.
***************************************************************************
***************************************************************************
* equates
***************************************************************************
MBAR EQU $0003FF00 Address of SIM40 Module Base Address Reg.
MODBASE EQU $FFFFF000 SIM40 MBAR address value
***************************************************************
* Serial module equates
SERIAL EQU $700 Offset from MBAR for serial module regs
MCRH EQU $0 serial MCR high byte
MCRL EQU $1 serial MCR low byte
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cale Semiconductor,
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