home *** CD-ROM | disk | FTP | other *** search
- ;
- ; B3AD-2.INS - BYE3 insert for AD Super Six CPU board - 07/30/85
- ;
- ; Z80 DART and 8116 baudrate generator
- ;
- ; This routine adapts the Advanced Digital Super Quad and Super Six
- ; single board computers to BYE3. Baudrate is read in off of a parallel
- ; port and sent to the baudrate generator upon powerup, from default
- ; jumpers. Note: This is an insert, not an overlay.
- ;
- ; = = = = = = = = = = = = = = = = = =
- ;
- ; 07/30/85 Restored to original format - pst
- ; 05/15/85 First version of B3AD - John Sojak
- ;
- ; = = = = = = = = = = = = = = = = = =
- ;
- ;
- DPORT EQU 02H ; Data port
- SPORT EQU DPORT+1 ; Modem control port
- BRPORT EQU 18H ; Set baud rate generator base port
- JUMPRS EQU 15H ; Baud rate default jumpers
- ;
- DAV EQU 00000001B ; Data available
- TBMT EQU 00000100B ; Transmit buffer empty
- DCD EQU 00001000B ; Data carrier detect
- ;
- ; Divisors for the 8116 baudrate geneator
- ;
- BD300 EQU 5 ; 300 baud
- BD1200 EQU 7 ; 1200 baud
- BD2400 EQU 10 ; 2400 baud
- ;
- ;-----------------------------------------------------------------------
- ;
- ; See if we still have a carrier - if not, return with the zero flag set
- ;
- MDCARCK:MVI A,10H ; Reset status
- OUT SPORT
- IN SPORT ; Get status
- ANI DCD ; Check for carrier
- RZ
- ORI 255
- RET
- ;
- ; Disconnect and wait for an incoming call
- ;
- MDINIT: MVI A,0 ; Setup to write register 0
- OUT SPORT
- MVI A,18H ; Reset channel
- OUT SPORT
- MVI A,4 ; Setup to write register 4
- OUT SPORT
- MVI A,44H ; Set 16x, 1 stop bit, no parity
- OUT SPORT
- MVI A,3 ; Setup to write register 3
- OUT SPORT
- MVI A,0C1H ; 8 bits, Rx enable
- OUT SPORT
- MVI A,5 ; Setup to write register 5
- OUT SPORT
- MVI A,68H ; DTR off
- OUT SPORT
- ;
- PUSH B ; Save in case it's being used elsewhere
- MVI B,20 ; 2 second delay to drop any carrier
- OFFTI: CALL DELAY ; 1 second delay
- DCR B
- JNZ OFFTI ; Keep looping until finished
- POP B ; Restore 'BC'
- ;
- MVI A,5 ; Setup to write register 5
- OUT SPORT
- MVI A,0E8H ; Turn DTR back on
- OUT SPORT
- ;
- IF IMODEM ; If using an intellegent modem
- CALL IMINIT ; Go initialize it now
- ENDIF ; IMODEM
- ;
- RET
- ;
- ; Input a character from the modem port
- ;
- MDINP: IN DPORT ; Get character
- RET
- ;
- ; Check the status to see if a character is available. If not, return
- ; with the zero flage set. If yes, use 0FFH to clear the flag.
- ;
- MDINST: IN SPORT ; Get status
- ANI DAV ; Got a character
- RZ ; Return if none
- ORI 255 ; Otherwise set the proper flag
- RET
- ;
- ; Send a character to the modem
- ;
- MDOUTP: OUT DPORT ; Send it
- RET
- ;
- ; See if the output is ready for another character
- ;
- MDOUTST:IN SPORT ; Get status
- ANI TBMT ; Ready for a character?
- RZ
- ORI 255
- RET
- ;
- ; Reinitialize the modem and hang up the phone by dropping DTR and
- ; leaving it inactive.
- ;
- MDQUIT: IF IMODEM
- CALL IMQUIT
- ENDIF ; IMODEM
- ;
- ; Called by the main program after caller types BYE
- ;
- MDSTOP: MVI A,5 ; Setup to write register 5
- OUT SPORT
- MVI A,68H ; Turn off DTR until next time
- OUT SPORT
- RET
- ;
- ; The following routine sets the baudrate. BYE5 asks for the maximum
- ; speed you have available.
- ;
- SET300: MVI A,BD300
- JMP SETBAUD
- ;
- SET1200:MVI A,BD1200
- JMP SETBAUD
- ;
- SET2400:MVI A,BD2400
- ;
- ; Sets the baudrate
- ;
- SETBAUD:RLC ; Shift the nibble over to the LSN
- RLC ; (could have been eliminated in the
- RLC ; equate but the intent is easier to
- RLC ; understand this way.
- ANI 11110000B ; Mask off bits - intent again
- PUSH B
- MOV B,A
- IN JUMPRS ; Get the console baud jumpers
- ANI 00001111B ; Mask garbage - 4 bits worth of it
- ORA B ; and make a composite of modem and
- OUT BRPORT ; console then tell the generator
- POP B
- XRA A ; Say baudrate is ok
- RET
- ; end
- ;-----------------------------------------------------------------------