Specifications

Application Examples
PUT ACC_MODC,ACC_MODC_INIT
; MASK INTERRUPTS
PUT ACC_INTC,ACC_INTC_INIT
; RESTORE REGISTER CONTENTS
POP DX
POP AX
ACC_INIT ENDP
;
V40 SERIAL CONTROLLER PROCEDURE
; THE V40 SERIAL CONTROLLER IS AN 8251 COMPATIBLE ASYNCHRONOUS
; COMMUNICATION CHANNEL CONFIGURED AS THREE-WIRE (TRANSMIT
; DATA, RECEIVE DATA, AND GROUND) RS-232 DTE. THE PROCEDURE
; SHOWN BELOW INITIALIZES THE V40 SCU WITH THE FOLLOWING
; PARAMETERS:
;
; SCU AND TCU ENABLED
; SCU BASE ADDRESS OF 00B0H
; TCU BASE ADDRESS OF 0040H
; BAUD RATE 9600
; DATA BITS 8
; STOP BITS 1
; PARITY NONE
; INTERRUPTS DISABLED
;
; ONCE THE SERIAL PORT IS INITIALIZED AS SHOWN BELOW, IT IS
; READY TO TRANSMIT AND RECEIVE CHARACTERS.
;
; INPUTS: NONE
; OUTPUTS: SERIAL PORT INITIALIZED
; CALLS: NONE
; DESTROYS: FLAGS
SCU_INIT PROC
; PRESERVE REGISTER STATUS
PUSH AX
PUSH DX
; INITIALIZE V40 CONFIG REGS
PUT OPCN,OPCN_INIT
PUT OPSEL,OPSEL_INIT_S+OPSEL_INIT_T
PUT OPHA,OPHA_INIT
PUT TULA,TULA_INIT
PUT SULA,SULA_INIT
PUT TCKS,TCKS_INIT
; SET BAUD RATE
PUT TCU_MODE,TCU_MODE_INIT
PUT TCU_TMR1,TCU_TMR1_BD1
PUT TCU_TMR1,TCU_TMR1_BD2
; SET SERIAL CHARACTER ATTRIBUTES
PUT SCU_MODE,SCU_MODE_INIT
; ENABLE TXD AND RXD
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