;
; (DELETE ABOVE TITLE LINE IF ASSEMBLING WITH ASM)
;
; SmartCat overlay for MEX: revision 1.0
; Written 05/15/84 by Curt Arnold
; Borrows heavily from
; Smartmodem overlay for MEX: revision 1.0
; Written 04/16/84 by Ronald G. Fowler
;
; Last revision: 05/15/84 (CWA)
;
; This modules adapts MEX for the Novation SmartCat.
; The main function of this module is to provide dialing capability;
; the disconnect vector and break vector are ancillary.
; You may use this module as a model to develop dialing routines
; for non-standard modems (e.g., the Racal-Vadic). The only
; pertinent entry point is the DIAL routine; you'll find entry
; specs for that below.
;
; There are two equates that you might want to change in this
; module. One is the DISC equate below -- if left on, MEX will
; use the SmartCat's disconnect code. If you prefer to
; provide your own in your overlay's DISCV vector (e.g.,
; by dropping DTR), then set DISC to FALSE and re-assemble.
; (If you don't understand this, then play it safe, and
; leave the equate set as it is). The other is the BREAK equate
; -- if left on, MEX will use the SmartCat break code.
;
; This overlay will work with any modem overlay that terminates
; prior to 0B00H
;
FALSE EQU 0
TRUE EQU NOT FALSE
CMDCHR EQU '%' ;DEFAULT SMARTCAT COMMAND CHARACTER
;
;
DISC EQU TRUE ;<<== CHANGE TO FALSE IF YOU DISC. WITH DTR
BREAK EQU TRUE ;<<== CHANGE TO FALSE IF YOU BREAK WITH DTR
;
; SYSTEM CONSTANTS
;
TPULSE EQU 0105H ;TONE/PULSE FLAG IN MODEM OVERLAY
DIALV EQU 0162H ;LOCATION OF DIAL VECTOR IN OVERLAY
DISCV EQU 0165H ;LOCATION OF DISCONNECT VECTOR IN OVERLAY
BREAKV EQU 0180H ;LOCATION OF BREAK VECTOR IN OVERLAY
DIALOC EQU 0B00H ;DIALING CODE GOES HERE
MEX EQU 0D00H ;"CALL MEX"
;
; FOLLOWING ARE FUNCTION CODES FOR THE MEX SERVICE CALL PROCESSOR
;
INMDM EQU 255 ;RETURN CHAR FROM MDM IN A, CY=NO CHR IN 100MS
TIMER EQU 254
TMDINP EQU 253 ;B=# SECS TO WAIT FOR CHAR, CY=NO CHAR
CHEKCC EQU 252 ;CHECK FOR ^C FROM KBD, Z=PRESENT
SNDRDY EQU 251 ;TEST FOR MODEM-SEND READY
RCVRDY EQU 250 ;TEST FOR MODEM-RECEIVE READY
SNDCHR EQU 249 ;SEND A CHARACTER TO THE MODEM (AFTER SNDRDY)
RCVCHR EQU 248 ;RECV A CHAR FROM MODEM (AFTER RCVRDY)
;
CR EQU 13
LF EQU 10
;
;
;
ORG DIALV ;OVERLAY THE DIALING VECTOR
JMP DIAL
;
IF DISC ;IF PROVIDING DISCONNECT CODE
ORG DISCV ;OVERLAY THE VECTOR
JMP DISCON
ENDIF
;
IF BREAK ;IF PROVIDING BREAK CODE
ORG BREAKV
JMP SENDBK
ENDIF
;
; This is the DIAL routine called by MEX to dial a digit. The digit
; to be dialed is passed in the A register. Note that two special
; codes must be intercepted as non-digits: 254 (start dial sequence)
; and 255 (end-dial sequence). Mex will always call DIAL with 254
; in the accumulator prior to dialing a number. Mex will also call
; dial with 255 in A as an indication that dialing is complete. Thus,
; the overlay may use these values to "block" the number, holding it
; in a buffer until it is completely assembled (in fact, that's the
; scheme employed here for the SmartCat).
;
; After the 254-start-dial sequence, MEX will call the overlay with
; digits, one-at-a-time. MEX will make no assumptions about the dig-
; its, and will send each to the DIAL routine un-inspected (some modems,
; like the SmartCat, allow special non-numeric characters in the
; phone number, and MEX may make no assumptions about these).
;
; After receiving the end-dial sequence (255) the overlay must take
; whatever end-of-dial actions are necessary *including* waiting for
; carrier at the distant end. The overlay should monitor the keyboard
; during this wait (using the MEX keystat service call), and return
; an exit code to MEX in the A register, as follows:
;
; 0 - Carrier detected, connection established
; 1 - Far end busy (only for modems that can detect this condition)
; 2 - No answer (or timed out waiting for modem response)
; 3 - Keyboard abort (^C only: all others should be ignored)
; 4 - Error reported by modem
;
; <No other codes should be returned after an end-dial sequence>
;
; The overlay should not loop forever in the carrier-wait routine, but
; instead use either the overlay timer vector, or the INMDMV (timed 100
; ms character wait) service call routine.
;
; The DIAL routine is free to use any of the registers, but must return
; the above code after an end-dial sequence
;
ORG DIALOC
;
DIAL: LHLD DIALPT ;FETCH POINTER
CPI 254 ;START DIAL?
JZ STDIAL ;JUMP IF SO
CPI 255 ;END DIAL?
JZ ENDIAL ;JUMP IF SO
;
; Not start or end sequence, must be a digit to be sent to the modem
;
MOV M,A ;PUT CHAR IN BUFFER
INX H ;ADVANCE POINTER
SHLD DIALPT ;STUFF PNTR
RET ;ALL DONE
;
; Here on a start-dial sequence
;
STDIAL: LXI H,DIALBF ;SET UP BUFFER POINTER
SHLD DIALPT
RET
;
; Here on an end-dial sequence
;
ENDIAL: MVI M,CR ;STUFF END-OF-LINE INTO BUFFER
INX H ;FOLLOWED BY TERMINATOR
MVI M,0
LDA TPULSE ;GET OVERLAY'S TOUCH-TONE FLAG
CPI 'T'
MVI A,' '
JZ DOTONE
MVI A,'I' ;LOAD A WITH CHAR TO SET PULSE
DOTONE STA SCDIAL+3 ;PUT INTO STRING
LXI H,SCDIAL ;POINT TO DIALING STRING
CALL SCSEND ;SEND IT
;
; THE FOLLOWING LOOP WAITS FOR A RESULT FROM THE MODEM (UP TO
; 60 SECONDS: YOU MAY CHANGE THIS VALUE IN THE FOLLOWING LINE)
;
RESULT: MVI C,60 ;<<== MAXIMUM TIME TO WAIT FOR RESULT
SCWLP: PUSH B
MVI B,1 ;CHECK FOR A CHAR, UP TO 1 SEC WAIT
MVI C,TMDINP ;DO TIMED INPUT
CALL MEX
JC NOCHAR ;SKIP AROUND IF NO CHAR.
ANI 7FH ;STRIP HIGH BIT
CALL SCTEST ;CHECK CHAR
MOV A,B ;MOVE RETURN CODE TO A
JC NOCHAR ;NO CODE YET
PUSH PSW ;PUSH OUR GOOD RESULT
DRAIN: MVI C,INMDM ;DRAIN ANY OTHER CHARACTERS
CALL MEX
JNC DRAIN
POP PSW
POP B
RET ;RETURN TO MEX
NOCHAR: MVI C,CHEKCC ;CHECK FOR CTRL-C
CALL MEX
POP B
JNZ SCNEXT ;IF NOT, JUMP
MVI B,18H
MVI C,SNDCHR
CALL MEX ;SEND CTRL-X
MVI A,3 ;RETURN ABORT CODE
RET
SCNEXT: DCR C ;NO
JNZ SCWLP ;CONTINUE
;
; ONE MINUTE WITH NO MODEM RESPONSE (OR NO CONNECTION)
;
SCTIMO: MVI A,2 ;RETURN TIMEOUT CODE
RET
;
; MODEM GAVE US A RESULT, CHECK IT
;
SCTEST: PUSH PSW ;PUSH CURRENT CHAR
LDA LCHAR
CPI CMDCHR
JZ SCANAL
POP PSW
STA LCHAR
STC ;SET CARRY FLAG
RET
SCANAL: POP PSW
STA LCHAR
MVI B,0 ;PREP CONNECT CODE
CPI 'C' ;"CONNECT"?
RZ
CPI '4' ;NUMERIC VERSION OF "CONNECT"
RZ
INR B ;PREP BUSY CODE B=1
CPI 'B'
RZ
CPI '0' ;NUMERIC VERSION OF "BUSY"
RZ
INR B ;PREP NO CONNECT MSG B=2
CPI 'N' ;N=NO ANS OR NO DIAL
RZ
CPI '2' ;NUMERIC VERSION OF "NO ANS"
RZ
CPI '3' ;NUMERIC VERSION OF "NO DIAL"
RZ
MVI B,4 ;PREP MODEM ERROR
CPI 'A' ;A = ABORT
RZ
;
; UNKNOWN RESPONSE, RETURN CARRY TO CALLER.
;
STC
RET
LCHAR DB 0H ;LAST CHAR PROCESSED
;
; FOLLOWING ROUTINE DISCONNECTS THE MODEM USING SMARTCat
; CODES. ALL REGISTERS ARE AVAILABLE FOR THIS FUNCTION.
; NOTHING RETURNED TO CALLER.
;
IF DISC
;
DISCON: LXI H,SCDISC ;SEND '%H'
CALL SCSEND
RET
;
SCDISC: DB CMDCHR,'H',CR,0
;
ENDIF
IF BREAK
;
SENDBK LXI H,SCBRK ;SEND '%B'
CALL SCSEND
RET
;
SCBRK: DB CMDCHR,'B 2',CR,0
;
ENDIF
;
; SMARTCat UTILITY ROUTINE: SEND STRING TO MODEM
;
SCSEND: MVI C,SNDRDY ;WAIT FOR MODEM READY
CALL MEX
ORA A
JZ SCSEND
MOV A,M ;FETCH NEXT CHARACTER
INX H
ORA A ;END?
RZ ;DONE IF SO
PUSH H
MOV B,A ;NO, POSITION FOR SENDING
MVI C,SNDCHR ;NOPE, SEND THE CHARACTER
CALL MEX
MVI C,INMDM ;CLEAR ANY STUFF FROM MODEM
CALL MEX
POP H
JMP SCSEND
;
; DATA AREA
;
SCDIAL: DB CMDCHR,'D '
DIALBF: DS 52 ;2* 24 CHAR MAX, + CR + NULL + SLOP
DIALPT: DS 2 ;DIAL POSITION POINTER
;
END