BAUDRATES FOR PORT P0 BAUDTB: DB 02H ;110 DB 05H ;300 DB 0 ;450 (not supported) DB 06H ;600 DB 0 ;710 (not supported) DB 07H ;1200 DB 0AH ;2400 DB 0CH ;4800 DB 0EH ;9600 DB 0FH ;19200 ; ; SET PARITY command: reset transmit/receive parity ; ; Parity is controlled by bits 0 and 1 of ; the byte sent to the SIO write-register ; 4 as follows: ; ; Parity Bit 1 Bit 0 ; Off - 0 ; Odd 0 1 ; Even 1 1 ; ; ; SET STOPBITS command: reset number of stop bits ; ; The number of stop bits is controlled by bits ; 2 and 3 of the byte sent to the SIO write- ; register 4, as follows: ; ; Stop bits Bit 3 Bit 2 ; 1 0 1 ; 1.5 1 0 ; 2 1 1 ; ; ; SET LENGTH command: set bits per character ; ; The number of bits per character is controlled for ; the receiver circuit by bits 6 and 7 of the byte ; sent to the SIO write-register 3 and for the trans- ; mitter circuit by bits 5 and 6 of the byte sent to ; the SIO write-register 5. The assumption has been ; made here that both transmission and reception will ; be carried on at the same number of bits per charac- ; ter. The bit configurations are shown for register ; 3 only, but are the same for register 5: ; ; BPC Bit 7 Bit 6 ; 5 0 0 ; 6 1 0 ; 7 0 1 ; 8 1 1 ; ;========================================================================== ; Data Area ;========================================================================== ; ; Default UART parameters (Initalized for External RS-232) ; REG0: DB 00011000B ;RESET CHANNEL A REG3: DB 11000001B ;ENABLE RECEIVE AT 8 BITS/CHAR REG4: DB 01000100B ;NO PARITY, 1 STOP BIT, CLOCK X16 REG5: DB 11101010B ;ENABLE TRANSMIT AT 8 BITS/CHAR ER5: DB 11101010B ;EXTERNAL MDM CTRL REGISTER 5 (Initial value) WR5: DB 01101000B ;INTERNAL MDM CTRL REGISTER 5 (Initial value) ;