CP/M/CPM_CDROM.iso/cpm/mex/mxo-sn10.asm

Assembly Source File | 1994-07-13 | 38.8 KB | 1,112 lines

;    Title    'MEX overlay for the Sanyo MBC-1200/1250 Computer'
;
;     This file adapts the Sanyo MBC-1200/1250 to the MEX modem program.
;
;    Created:    06/15/87    Last Modification:  06/15/87
;
;    NOTE:    Once you get this overlay into MEX, I heartily recommend
;        that you adjust the page size and clock speed in the running
;        program. To do the former, type 'STAT PAGE 33' and hit
;        <ENTER> at the MEX:A0>> prompt. To do the latter, time
;        a 60 second or so MEX 'SLEEP' command and adjust the
;        clock speed with 'STAT CLOCK'. Once you've got it right,
;        use the 'CLONE' command to make a permanent version.
;
;     You will want to look this file over carefully. There are a number of
;     options that you can use to configure the program to suit your taste.;
;     Edit for your preferences, reassemble, and MLOAD the *.HEX file into
;    MEX as described in its documentation.
;____________________________________________________________________________
;
;    SOME GENERAL NOTES:
;
;    There are a variety of notes regarding how the overlay works, why it
;    is the way it is, what you can and can't do with it included here.
;
;    This overlay is intelligent regarding the SANYO 12## and stupid
;    regarding any specific modems. It has been debugged using a
;    SANYO 1250.
;
;    If you need to add code for your particular modem, likely spots for
;    its inclusion are after the 8215 chip mode initialization in the
;    NITMOD (initialize modem) routine and in the SET command handler
;    routine. You can get some general ideas from the Sanyo 1000 overlay
;    source by scanning for their SmartModem equate in IF clauses with
;    your editor and looking at what is done there. Most modem support
;    above and beyond initialization and SET command support seems more
;    appropriate in a separate overlay...
;
;    Relatively complete documentation of the 8251 usart used is included
;    in comments preceding the fixed format data area, along with equates
;    for the various mode word fields, etc. You can use this information
;    and the equates to adjust the operation of the overlay and to modify
;    any routines you want to...
;
;    If you wish to use this overlay with some SmartModem overlay, bear
;    in mind that it must end before that one starts.
;
;    The SET command implemented in this overlay gives relatively full
;    control of the 8251 usart used by the Sanyo 12##'s for RS232C
;    interface imlementation. More than you are likely to use. The modem
;    specific stuff is pretty much up to you. Code for a "SET DIAL"
;    command that sets the TPULSE flag byte (location 105H) used by
;    SmartModem overlays for TOUCH/PULSE dialing control was left in
;    IF clauses controlled by the DIALSET equate. This command does
;    nothing but set the flag one way or another. You need more code
;    to actually make it do something useful (such code might live in
;    a separate overlay source code fiel such as the one(s) for the
;    SmartModem), but it's there if you want it. Set the DIALSET equate
;    to YES if you do.
;
;    Further information on the SET command can be found near the code
;    actually implements it. Search for the string "SET COMMAND" and
;    you shall be rewarded...
;____________________________________________________________________________
;
;    BAUD RATE NOTES:
;
;     Use the "SET" command to change the baudrate when desired.  It starts
;     out at 1200 baud when the program is first called up.
;
;     Only 300 & 1200 Baud are enabled. Due to the way the Sanyo 12##'s are
;    designed, anything else requires modifying the positions of baud rate
;    jumpers in the box.
;
;    *********************************************************************
;    NOTE:    Since the Sanyos basically control the baud rate thru
;        jumpering, it follows that there is a right way and a wrong
;        way for those jumpers to be set when using this program. It
;        just so happens that the default factory setting is 1200 baud
;        in the 8251 usart chip 16x mode, which is exactly what we want
;        here. This allows us to go to 64x mode and get 300 baud on
;        those unfortunate and unusual occasions when we want it.
;        Since the 8251 clock rate divisor modes are in multiples of
;        four, there is no way I know of to get both 2400 and 1200
;        baud out of the same jumper setting. You could wire in a
;        switch... Nonetheless, one of these days, if you still have
;               this box when 4800 baud becomes the vogue, the code changes
;               will be simplicity itself.
;    *********************************************************************
;____________________________________________________________________________
;
;    CREDIT WHERE CREDIT IS DUE DEPARTMENT:
;
;    This overlay file originated in the overlay for the SANYO 1000
;    called MXO-SY21.ASM, which in turn originated someplace else....
;
;    The hardware is different enough that quite a large portion of the
;    code here is either new or re-arranged to suit my quirky mentality.
;    Nonetheless, much has been retained, and never having done any code
;    of this variety before, my thanks to Bob Sandel, who wrote the
;    overlay for the 1000.
;
;____________________________________________________________________________
;
REV    EQU    10        ; Overlay revision level
;
;     Miscellaneous equates
;
YES    EQU    0FFH
NO    EQU    0
ALLBITS EQU    11111111B
;
;    ASCII character equates
;
BELL    EQU    07H        ; Bell
TAB    EQU    09H        ; Tab
LF    EQU    0AH        ; Line feed
CR    EQU    0DH        ; Carriage return
ESC    EQU    1BH        ; Escape
;
;     Note that all overlays may freely use memory up to 0CFFH.  If your
;     overlay must work with the MEX Smartmodem overlay (MXO-SMxx.ASM) or
;     the MEX DATEC 212 overlay (MXO-DT10.ASM), the physical modem overlay
;     should terminate by 0AFFH. Refer to the docs for any others.
;
TPA    EQU    0100H        ; Transient Program Area
MEX    EQU    0D00H        ; Address of the service processor
;
;    The following equate determines whether code is included to
;    set the TPULSE dial flag that I must assume is used by some
;    modem overlays. I have no use for it. You may.
;
DIALSET EQU    NO        ; Include SET DIAL command?
;
PORT    EQU    0EDH        ; Sanyo 8251 modem USART control port
MODCTL    EQU    PORT        ; MODEM CONTROL PORT
MODDAT    EQU    PORT-1        ; MODEM DATA PORT
;____________________________________________________________________________
;
;    SOME DOCUMENTATION ON THE 8251 USART USED IN THE SANYO(S)
;    and equates usable for controlling most of the stuff...
;____________________________________________________________________________
;
;    8251A chip mode word bit definitions
;
;    The initial data used to construct a mode word for the 8251
;    chip in default operation is located in the overlay data area
;    that follows the first fixed data area that is understood by MEX.
;    This area starts around address 01A7H and has a comment containing
;    the string "OVERLAY DATA AREA" if you want to scan for it...
;
;    +------+------+------+------+------+------+------+------+
;    | DB7  | DB6  | DB5  | DB4  | DB3  | DB2  | DB1  | DB0  |
;    +------+------+------+------+------+------+------+------+
;    | S2   | S1   | EP   | PEN  | L2   | L1   | B2   | B1   |
;    +------+------+------+------+------+------+------+------+
;    |      |      |      |      |      |      |      |
;     |+-----+      |      |      |      |      |      |
;    ||+-----------+      |      |      |      |      |
;    |||+-----------------+      |      |      |      |
;    ||||+-----------------------+      |      |      |
;    |||||+-----------------------------+      |      |
;    ||||||+-----------------------------------+      |
;    |||||||+-----------------------------------------+
;    ||||||||
;    ||||||||
;    |||||||+---------> 0    1    0    1
;    ||||||+----------> 0    0    1    1
;    ||||||       MODE: SYNC 1X   16X  64X
;    ||||||
;    |||||+-----------> 0    1    0    1
;    ||||+------------> 0    0    1    1
;    ||||         CHAR: 5    6    7    8  (BITS)
;    ||||
;    |||+-------------> PARITY: 1=ENABLE, 0=DISABLE
;    |||
;    ||+--------------> PARITY: 1=EVEN,   0=ODD
;    ||
;    |+---------------> 0    1    0    1
;    +----------------> 0    0    1    1
;             STOP: N/A  1    1.5  2  (BITS)
;
;    Most of the above is self-explanatory. One comment on the MODE
;    settings 1x, 16, 64x. These are specifications that essentially
;    tell the usart chip, "the clock input you are getting is this
;    many times faster than it should be..." What this means is that
;    the 1, 16 or 64 that you specify is used by the chip to divide
;    the clock rate before using it. That is why using 16x as standard
;    for 1200 baud, we can goto 300 baud by switching to 64x, since:
;         1200/300=4=64/16 or (1200*16)=(300*64)
;    Since I have no idea what or if the minimum usable clock rate is,
;    all bets are off if you rejumper your box and/or use 1x mode.
;    But by all means try it, if you need to...
;
;    Some mode equates:
;
;    Internal clock rate divisor
;
SYNC    EQU    00000000B    ; SYNC MODE (NOT USED)
X01    EQU    00000001B    ;   1X MODE (NOT USED)
X16    EQU    00000010B    ;  16X MODE 1200 BAUD
X64    EQU    00000011B    ;  64X MODE  300 BAUD
;
;    Character size
;
CHRLEN5 EQU    00000000B    ; CHAR = 5 BITS
CHRLEN6 EQU    00000100B    ; CHAR = 6 BITS
CHRLEN7 EQU    00001000B    ; CHAR = 7 BITS
CHRLEN8 EQU    00001100B    ; CHAR = 8 BITS
;
;    Parity enable/disable, even/odd
PTYENBL EQU    00010000B    ; ENABLE
PTYDSBL EQU    00000000B    ; DISABLE
PTYEVEN EQU    00100000B    ; EVEN
PTYODD    EQU    00000000B    ; ODD
;
;    Stop bit settings
;
STPB1    EQU    01000000B    ; 1 STOP BIT
STPB1H    EQU    10000000B    ; 1 1/2 STOP BITS
STPB2    EQU    11000000B    ; 2 STOP BITS
;
;    8251A chip command word bit definitions
;    +------+------+------+------+------+------+------+------+
;    | DB7  | DB6  | DB5  | DB4  | DB3  | DB2  | DB1  | DB0  |
;    +------+------+------+------+------+------+------+------+
;    | EH   | IR   | RTS  | ER   | SBRK | RXE  | DTR  | TXEN |
;    +------+------+------+------+------+------+------+------+
;    |      |      |      |      |      |      |      |
;     |+-----+      |      |      |      |      |      |
;    ||+-----------+      |      |      |      |      |
;    |||+-----------------+      |      |      |      |
;    ||||+-----------------------+      |      |      |
;    |||||+-----------------------------+      |      |
;    ||||||+-----------------------------------+      |
;    |||||||+-----------------------------------------+
;    ||||||||
;    ||||||||
;    |||||||+---------> TRANSMIT: 1=ENABLE, 0=DISABLE
;    |||||||
;    ||||||+----------> DATA TERMINAL READY:  1=FORCE (NOT DTR) TO ZERO
;    ||||||
;    |||||+-----------> RECEIVE:  1=ENABLE, 0=DISABLE
;    |||||
;    ||||+------------> SEND BREAK CHARACTER: 1=FORCE (TXD) TO ZERO
;    ||||
;    |||+-------------> ERROR RESET:      1=RESET FLAGS PE, OE, FE
;    |||
;    ||+--------------> REQUEST TO SEND:     1=FORCE (NOT RTS) TO ZERO
;    ||
;    |+---------------> INTERNAL RESET:     1=GOTO MODESET MODE
;    |
;    +----------------> ENTER HUNT MODE:     1=ENABLE SEARCH FOR SYNC CHRS
;                         (NO EFFECT IN ASYNC MODE)
;
;    NOTE: MUST PERFORM ERROR RESET WHENEVER RXE AND EH ARE PROGRAMMED.
;
;    Some command equates
;
EH    EQU    10000000B    ; ENTER  HUNT MODE
IR    EQU    01000000B    ; INTERNAL RESET
RTS    EQU    00100000B    ; REQUEST TO SEND
ER    EQU    00010000B    ; ERROR RESET
SBRK    EQU    00001000B    ; SEND BREAK CHARACTER
RXE    EQU    00000100B    ; RECEIVE ENABLE
DTR    EQU    00000010B    ; DATA TERMINAL READY
TXEN    EQU    00000001B    ; TRANSMIT ENABLE
;
;    8251A chip status word bit definitions
;    +-------+-------+-------+-------+-------+-------+-------+-------+
;    | DB7   | DB6   | DB5   | DB4   | DB3   | DB2   | DB1   | DB0   |
;    +-------+-------+-------+-------+-------+-------+-------+-------+
;    | DSR   | SYNDET| FE    | OE    | PE    |TXEMPTY| RXRDY | TXRDY |
;    +-------+-------+-------+-------+-------+-------+-------+-------+
;    |       |       |       |       |       |       |       |
;     |+------+       |       |       |       |       |       |
;    ||+-------------+       |       |       |       |       |
;    |||+--------------------+       |       |       |       |
;    ||||+---------------------------+       |       |       |
;    |||||+----------------------------------+       |       |
;    ||||||+-----------------------------------------+       |
;    |||||||+------------------------------------------------+
;    ||||||||
;    ||||||||
;    |||||||+---------> BIT HAS DIFFERENT MEANING FROM TXRDY OUTPUT PIN
;    |||||||           BIT NOT CONDITIONED BY (NOT CTS) AND TXEN.
;    |||||||               MEANS: DB BUFFER EMPTY
;    |||||||           PIN IS CONDITIONED BY POTH OF THE ABOVE.
;    |||||||               MEANS: DB BUFFER EMPTY * (CTS=0) * (TXEN=1)
;    |||||||
;    ||||||+----------> SAME AS I/O PIN
;    ||||||
;    |||||+-----------> SAME AS I/O PIN
;    |||||
;    ||||+------------> PARITY ERROR: SET WHEN A PARITY ERROR IS DETECTED.
;    ||||           RESET BY COMMAND WORD ER BIT. DOESN'T INHIBIT 8251
;    ||||
;    |||+-------------> OVERRUN ERROR: SET WHEN CPU DOESN'T READ A CHAR
;    |||           BEFORE NEXT IS AVAILABLE. RESET BY ER BIT OF
;    |||           COMMAND WORD. DOESN'T INHIBIT 8251 OPERATION.
;    |||
;    ||+--------------> FRAMING ERROR: SET WHEN VALID STOP BIT IS NOT
;    ||           DETECTED AT THE END OF EVERY CHARACTER. RESET BY
;    ||           ER BIT OF COMMAND WORD. DOESN'T INHIBIT 8251.
;    ||
;    |+---------------> SAME AS I/O PIN.
;    |
;    +----------------> DATA SET READY: INDICATES DSR IS AT ZERO
;
;    Some status equates
;
DSR    EQU    10000000B    ; DATA SET READY
SYNDET    EQU    01000000B    ;
FE    EQU    00100000B    ; FRAMING ERROR
OE    EQU    00010000B    ; OVERRUN ERROR
PE    EQU    00001000B    ; PARITY ERROR
TXEMPTY EQU    00000100B    ;
RXRDY    EQU    00000010B    ;
TXRDY    EQU    00000001B    ;
;
;    Various byte equate values constructed from the above follow..
;
RESET1    EQU    EH+RXE+DTR+TXEN    ; Initialize UART
RESET2    EQU    IR        ; Internal reset
CHIPSET EQU    RTS+RXE+DTR+TXEN ; DTR, RTS, RE, TE
DISCNT    EQU    ER+RXE+DTR+TXEN    ; No DTR, RTS, RE, TE
;
;  Progammable Baud Rate factors (theoretical)
;
NA    EQU    0FFH        ; Value for baud rate not available
;
BD110    EQU    NA        ; NO 110    BAUD RATE 0
BD300    EQU    X64        ; <300>         BAUD RATE 1
BD450    EQU    NA        ; NO 450        BAUD RATE 2
BD600    EQU    NA        ; NO 600        BAUD RATE 3
BD710    EQU    NA        ; NO 710        BAUD RATE 4
BD1200    EQU    X16        ; <1200>    BAUD RATE 5
BD2400    EQU    NA        ; NO 2400       BAUD RATE 6
BD4800    EQU    NA        ; NO 4800       BAUD RATE 7
BD9600    EQU    NA        ; NO 9600       BAUD RATE 8
BD19K    EQU    NA        ; NO 19200      BAUD RATE 9
;____________________________________________________________________________
;
;     MEX service processor stuff ... MEX supports an overlay service
;     processor, located at 0D00H (and maintained at this address from
;     version to version).  If your overlay needs to call BDOS for any
;     reason, it should call MEX instead; function calls below about
;     240 are simply passed on to the BDOS (console and list I/O calls
;     are specially handled to allow modem port queueing, which is why
;     you should call MEX instead of BDOS).  MEX uses function calls
;     above about 244 for special overlay services (described below).
;
;     Some sophisticated overlays may need to do file I/O; if so, use
;     the PARSFN MEX call with a pointer to the FCB in DE to parse out
;     the name.  This FCB should support a spare byte immediately pre-
;     ceeding the actual FCB (to contain user # information).  If you've
;     used MEX-10 for input instead of BDOS-10 (or you're parsing part
;     of a SET command line that's already been input), then MEX will
;     take care of DU specs, and set up the FCB accordingly.  There-
;     after all file I/O calls done through the MEX service processor
;     will handle drive and user with no further effort necessary on
;     the part of the programmer.
;
INMDM    EQU    255        ; Get char from port to A, CY=no more in 100 ms
TIMER    EQU    254        ; Delay 100ms * reg B
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)
LOOKUP    EQU    247        ; Table search: see CMDTBL comments for info
PARSFN    EQU    246        ; Parse filename from input stream
BDPARS    EQU    245        ; Parse baud-rate from input stream
SBLANK    EQU    244        ; Scan input stream to next non-blank
EVALA    EQU    243        ; Evaluate numeric from input stream
LKAHED    EQU    242        ; Get nxt char w/o removing from input
GNC    EQU    241        ; Get char from input, cy=1 if none
ILP    EQU    240        ; Inline print
DECOUT    EQU    239        ; Decimal output
PRBAUD    EQU    238        ; Print baud rate
;
CONOUT    EQU    2        ; Simulated BDOS function 2: console char out
PRINT    EQU    9        ; Simulated BDOS function 9: print string
INBUF    EQU    10        ; Input buffer, same structure as BDOS 10
;_____________________________________________________________________________
;
;    BEGIN FIXED FORMAT DATA AREA
;    This data area is layed out in a format understood by MEX.
;    Don't mess with the ordering of data here, as it is used to
;    synchronize the operations of MEX with this and any other
;    overlay(s) you may be using.
;
    ORG    TPA        ; We begin
;
    DS    3        ; MEX has a JMP START here
;
;     The following variables are located at the beginning of the program
;     to facilitate modification without the need of re-assembly. They will
;     be moved in MEX 2.0.
;
PMODEM:    DB    NO        ; Yes=PMMI modem   (not referenced by MEX)
SMODEM:    DB    NO        ; Yes=Smartmodem   (not referenced by MEX)
TPULSE:    DB    'P'        ; T=touch, P=pulse (not referenced by MEX)

;    NOTE:    This peculiar clock speed was set by timing the
;        MEX 'SLEEP' command on my box. If yours is different,
;        just change it with 'STAT CLOCK' and 'CLONE' MEX.
CLOCK:    DB    47        ; Clock speed x .1, up to 25.5 mhz.
MSPEED:    DB    5        ; Sets initial baud rate
                ; 0=110    1=300  2=450  3=600  4=710
                ; 5=1200 6=2400 7=4800 8=9600 9=19200
BYTDLY:    DB    5        ; Default time to send character in
                ; Terminal mode file transfer (0-9)
                ; 0=0 delay, 1=10 ms, 5=50 ms, 9=90 ms
CRDLY:    DB    5        ; End-of-line delay after CRLF in terminal
                ; Mode file transfer for slow BBS systems
                ; 0=0 delay, 1=100 ms, 5=500 ms, 9=900 ms
COLUMS:    DB    5        ; Number of directory columns
SETFL:    DB    YES        ; Yes=user-defined SET command
SCRTST:    DB    YES        ; Yes=if home cursor and clear screen
                ; Routine at CLRSCRN
    DB    0        ; Was once ACKNAK, now spare
BAKFLG:    DB    NO        ; Yes=make .BAK file
CRCDFL:    DB    YES        ; Yes=default to CRC checking
                ; No=default to Checksum checking
TOGCRC:    DB    YES        ; Yes=allow toggling of Checksum to CRC
CVTBS:    DB    NO        ; Yes=convert backspace to rub
TOGLBK:    DB    YES        ; Yes=allow toggling of bksp to rub
ADDLF:    DB    NO        ; No=no LF after CR to send file in
                ; Terminal mode (added by remote echo)
TOGLF:    DB    YES        ; Yes=allow toggling of LF after CR
TRNLOG:    DB    NO        ; Yes=allow transmission of logon
                ; Write logon sequence at location LOGON
SAVCCP:    DB    YES        ; Yes=do not overwrite CCP
LOCNXT:    DB    NO        ; Yes=local cmd if EXTCHR precedes
                ; No=not local cmd if EXTCHR precedes
TOGLOC:    DB    YES        ; Yes=allow toggling of LOCNXTCHR
LSTTST:    DB    YES        ; Yes=allow toggling of printer on/off
                ; In terminal mode. Set to no if using
                ; The printer port for the modem
XOFTST:    DB    NO        ; Yes=allow testing of XOFF from remote
                ; While sending a file in terminal mode
XONWT:    DB    NO        ; Yes=wait for XON after sending CR while
                ; Transmitting a file in terminal mode
TOGXOF:    DB    YES        ; Yes=allow toggling of XOFF testing
IGNCTL:    DB    YES        ; Yes=do not send control characters
                ; Above CTL-M to CRT in terminal mode
                ; No=send any incoming CTL-char to CRT
EXTRA1:    DB    0        ; For future expansion
EXTRA2:    DB    0        ; For future expansion
BRKCHR:    DB    '@'-40H        ; ^@ = Send a 300 ms. break tone
NOCONN:    DB    'N'-40H        ; ^N = Disconnect from phone line
LOGCHR:    DB    'L'-40H        ; ^L = Send logon
LSTCHR:    DB    'P'-40H        ; ^P = Toggle printer
UNSVCH:    DB    'R'-40H        ; ^R = Close input text buffer
TRNCHR:    DB    'T'-40H        ; ^T = Transmit file to remote
SAVCHR:    DB    'Y'-40H        ; ^Y = Open input text buffer
EXTCHR:    DB    '^'-40H        ; ^^ = Send next character
;
    DS    2        ; Not used - only for PMMI routines
;
;     Low-level modem I/O routines: this will be replaced with
;     a jump table in MEX 2.0 (you can insert jumps here to longer
;     routines if you'd like ... I'd recommend NOT putting part of
;     a routine in this area, then jumping to the rest of the routine
;     in the non-fixed area; that will complicate the 2.0 conversion)
;
INCTL:    IN    MODCTL        ; In modem control port
    RET
    DB    0,0,0,0,0,0,0    ; Spares if needed
;
OTDATA:    OUT    MODDAT        ; Out modem data port
    RET
    DB    0,0,0,0,0,0,0    ; Spares if needed
;
INPORT:    IN    MODDAT        ; In modem data port
    RET
    DB    0,0,0,0,0,0,0    ; Spares if needed
;
;     Bit-test routines.  These will be merged with the above
;     routines in MEX 2.0 to provide a more reasonable format
;
MASKR:    ANI    RXRDY        ; Bit to test for receive ready
    RET
;
TESTR:    CPI    RXRDY        ; Value of receive bit when ready
    RET
;
MASKS:    ANI    TXRDY        ; Bit to test for send ready
    RET
;
TESTS:    CPI    TXRDY        ; Value of send bit when ready
    RET
;
;     Unused area: was once used for special PMMI functions.
;     Now used only to retain compatibility with MDM overlays.
;     You may use this area for any miscellaneous storage you'd
;     like but the length of the area *must* be 12 bytes.
;
    DS    12
;
;     Special modem function jump table: if your overlay cannot handle
;     some of these, change the jump to "DS 3", so the code present in
;     MEX will be retained.
;
LOGON:    DS    2        ; Needed for MDM compat, not ref'd by MEX
DIALV:    DS    3        ; Dial digit in A (see info at PDIAL)
DISCV:    DS    3        ; Disconnect the modem
GOODBV:    JMP    CPMEXT        ; Called before exit to CP/M
INMODV:    JMP    NITMOD        ; Initialization. Called at cold-start
NEWBDV:    JMP    SBAUD        ; Set baud rate
NOPARV:    DS    3        ; Set for no parity (called after transfer)
PARITV:    DS    3        ; Set modem parity (called before transfer)
SETUPV:    JMP    SETCMD        ; SET command
SPMENV:    DS    3        ; Not used with MEX
VERSNV:    JMP    SYSVER        ; Overlay's voice in the sign-on message
BREAKV:    JMP    SBREAK        ; Send a break
;
;     The following jump vector provides the overlay with access to special
;     routines in the main program (retained and supported in the main pro-
;     gram for MDM overlay compatibility). These should not be modified by
;     the overlay.
;
;     Note that for MEX 2.0 compatibility, you should not try to use these
;     routines, since this table will go away with MEX 2.0 (use the MEX
;     service call processor instead).
;
ILPRTV:    DS    3        ; Replace with MEX function 9
INBUFV:    DS    3        ; Replace with MEX function 10
ILCMPV:    DS    3        ; Replace with table lookup funct. 247
INMDMV:    DS    3        ; Replace with MEX function 255
NXSCRV:    DS    3        ; Not supported by MEX (returns w/no action)
TIMERV:    DS    3        ; Replace with MEX function 254
;
;     Clear/screen and clear/end-of-screen. Each routine must use the
;     full 9 bytes alloted (may be padded with nulls).
;
;     These routines (and other screen routines that MEX 2.0 will sup-
;     port) will be accessed through a jump table in 2.0, and will be
;     located in an area that won't tie the screen functions to the
;     modem overlay (as the MDM format does).
;
CLREOS:    LXI    D,EOSMSG    ; Null: no clear to end of screen
    MVI    C,PRINT
    CALL    MEX
    RET
;
CLS:    LXI    D,CLSMSG    ; Clear screen, home cursor
    MVI    C,PRINT
    CALL    MEX
    RET
;
;    END OF FIXED FORMAT AREA
;
;____________________________________________________________________________
;
;    BEGIN OVERLAY DATA AREA
;
;    The following data areas are used by the overlay code for various
;    operations MEX calls on it to perform. The ordering is not important
;    except where noted in the comments.
;
;    Some other data areas are scattered thruout the remainder of the file.
;    These are mostly tables referenced from discrete routines and are thus
;    most conveniently kept in the vicinity of those routines.
;
;    Sign-on Message
;    You can use this as an "eye-catcher" when debugging or patching
;    this file. Marks the beginning of the overlay data area.
;
SOMESG:
    DB    'Sanyo MBC-1200/1250 computer 300/1200 BAUD Version '
    DB    REV/10+'0','.'
    DB    REV MOD 10+'0',CR,LF
    DB    '$'
;
;     Strings to clear-to-end-of-screen, and clear-screen
;
EOSMSG:    DB    0,0,0,0,0,0,'$'    ; Clear to end-of-screen (0 for pause)
CLSMSG:    DB    1AH,0,0,0,0,0,'$' ; Clear whole screen (0 for pause)
;
;     Baud rate table
;
BTABL:    DB    BD110        ; The byte called MSPEED is used to
    DB    BD300        ;  index into this table to find the
    DB    BD450        ;   current baud rate. For example, if
    DB    BD600        ;    MSPEED equals 5, then the baud rate
    DB    BD710        ;     is 1200, since thatis the fifth entry
    DB    BD1200        ;      PAST the entry at BTABL.
    DB    BD2400        ;     To reset the baud rate, simply
    DB    BD4800        ;      MSPEED to the offset of the desired
    DB    BD9600        ;       baud and calling the SBAUD routine
    DB    BD19K        ;        suffices.
;
;    8251 mode bits, saved by bit group
;    The current values of the following bytes are or'ed together
;    to form an 8251 mode word and output to the chip in the MODESET
;    routine. Each byte represents certain bit positions in the mode
;    word, and no attempt at error checking is made in the MODESET
;    routine. The CLKMOD byte represents the baud rate used (300 or 1200)
;    and is only updated thru use of the SBAUD routine, which chooses
;    from the baud rate table above based on the MSPEED byte. It will
;    not update the baud if the value is bad.
;
CLKMOD:    DB    X16        ; Mode bits: CLOCK DIVISOR (X16=1200 baud)
CHRLEN:    DB    CHRLEN8        ; Mode bits: CHARACTER LENGTH
PARITY:    DB    PTYDSBL        ; Mode bits: PARITY
STOP:    DB    STPB1        ; Mode bits: STOP BITS
;
;    END OVERLAY DATA AREA
;
;____________________________________________________________________________
;
;    BEGIN EXECUTABLE CODE
;
;    Carrier Show and Carrier Detect deleted.
;    No carrier detect capability.
;
CARRSH:
CARRCK:
;
;     Exit routine --  called just before MEX exits to CP/M
;
CPMEXT:
;
;    DUMMY routine for calls that are not implemented.
;
DUMMY:    RET            ; We don't need one
;____________________________________________________________________________
;
;     Modem initialization.
;
NITMOD:    LDA    MSPEED        ; Get current baud rate setting
    CALL    SBAUD        ; Set the baudrate
    RET
;
;     Send-break routine
;
SBREAK:    MVI    A,SBRK+CHIPSET    ; Break control byte
    OUT    MODCTL        ; Output
    MVI    B,2        ; Wait 200 ms
    MVI    C,TIMER        ; MEX fcn code
    CALL    MEX        ; Time out
    MVI    A,CHIPSET    ; Reset break
    OUT    MODCTL        ; Output
    RET            ; Return to caller
;
;     Set Baud Rate
;
;     New baud-rate code in A.
;     NOTE: this routine (ie, the one vectored through NEWBDV) should
;     update MSPEED with the passed code, but ONLY if that rate is
;     supported by the hardware.
;
;     A=0:   110 baud       A=1:   300 baud      A=2:   450 baud
;     A=3:   600 baud       A=4:   710 baud      A=5:  1200 baud
;     A=6:  2400 baud       A=7:  4800 baud      A=8: 19200 baud
;
;    The only baud rates supported are 300 and 1200.
;
SBAUD:    PUSH    H        ; Don't alter anybody
    PUSH    D
    PUSH    B
    MOV    C,A        ; Save baud rate code
    MVI    B,0
    LXI    H,BTABL        ; Get baudrate value
    DAD    B        ; HL now contains address of baudrate number
    MOV    A,M        ; A  now contains baudrate n
    CPI    NA        ; See if baud rate valid
    STC            ; Set for not valid
    JZ    NOTVAL        ; Not valid: bypass setting it
;
;    Baud rate ok so set it
;
    STA    CLKMOD        ; Put new baud code in clock rate byte
    MOV    A,C        ; Get baud rate code  (for MEX)
    STA    MSPEED        ; Save baud rate code (for MEX)
    CALL    MODESET        ; Call routine to tell 8251 about it
    XRA    A        ; Clear carry flag
;
;    Return point for valid and not valid calls
;
NOTVAL:    POP    B        ; Restore registers and return
    POP    D
    POP    H
    RET
;
;    This code sets the 8251 chip mode from the mode bytes.
;    Multiple bytes, each representing certain bit positions
;    of the mode word are or'ed together here. MODESET is
;    intended to be called from setup routines.
;
;    The accumulator is trashed, flags are arbitrary.
;
MODESET:
    PUSH    H        ; HL is all we save here...
    MVI    A,RESET1    ; Insure out-of-mode state
    OUT    MODCTL        ; Modem control port
    MVI    A,RESET1    ; Do it again
    OUT    MODCTL        ; For slight extra delay
    MVI    A,RESET2    ; Then reset the USART
    OUT    MODCTL        ; Modem control port
    XTHL            ; Delay -- must be in pairs
    XTHL            ; Restore the glory that once was...
    LDA    CLKMOD        ; Get 8251 clock mode
    LXI    H,CHRLEN    ; Point at character length byte
    ORA    M        ; Set bits
    LXI    H,PARITY    ; Point at parity setting byte
    ORA    M        ; Set bits
    LXI    H,STOP        ; Point at stop bit setting byte
    ORA    M        ; Set bits
    OUT    MODCTL        ; 8251 Mode now set
    MVI    A,CHIPSET    ; Set chip for I/O
    OUT    MODCTL        ; 8251 Command now set
    IN    MODDAT        ; Clear data port
    POP    H        ; Get it back...
    RET            ; Return to caller
;
;     Sign-on message
;
SYSVER:
    CALL    CRLF        ; Skip a line
    LXI    D,SOMESG    ; Point to signon message
    MVI    C,PRINT        ; MEX print string
    CALL    MEX        ; Print message on term
    CALL    CRLF        ; Skip a line
    CALL    SETSH2        ; Show settings w/o scrn clr
;
;     Newline on console
;
CRLF:    MVI    A,CR
    CALL    TYPE
    MVI    A,LF        ; Fall into TYPE
;
;     type char in A on console
;
TYPE:    PUSH    H        ; Save 'em
    PUSH    D
    PUSH    B
    MOV    E,A        ; Align output character
    MVI    C,CONOUT    ; Print via MEX
    CALL    MEX
    POP    B
    POP    D
    POP    H
    RET
;____________________________________________________________________________
;
;    SET COMMAND NOTES (as implemented by this overlay):
;
;    SET STOPBIT <1/1.5/2>
;    SET CHARLEN <5/6/7/8>
;    SET BAUD    <1200/300>
;    SET PARITY  <EVEN/ODD/NONE>
;
;    Optional:
;    SET DIAL    <TOUCH/PULSE>
;____________________________________________________________________________
;
;     SET COMMAND processor and data - the rest of this overlay is
;    devoted to the implementation of the command and its options.
;
;     Control is passed here after MEX parses a SET command.
;
SETCMD:    CALL    CRLF        ; For better readability
    MVI    C,SBLANK    ; Any arguments?
    CALL    MEX
    JC    SETSHO        ; If not, go print out values
    LXI    D,CMDTBL    ; Parse command
    CALL    TSRCH        ; From table
    PUSH    H        ; Any address on stack
    RNC            ; If we have one, execute it
    POP    H        ; Nope, fix stack
SETERR:    LXI    D,SETEMS    ; Print error
    MVI    C,PRINT
    CALL    MEX
    RET
;
SETEMS:    DB    CR,LF,'SET command error',CR,LF,'$'
;
;     SET command table ... note that tables are constructed of command-
;     name (terminated by high bit=1) followed by word-data-value returned
;     in HL by MEX service processor LOOKUP.  Table must be terminated by
;     a binary zero.
;
;     Note that LOOKUP attempts to find the next item in the input stream
;     in the table passed to it in HL ... if found, the table data item is
;     returned in HL; if not found, LOOKUP returns carry set.
;
CMDTBL:    DB    '?'+80H        ; SET ?
    DW    STHELP
    DB    'BAU','D'+80H    ; SET BAUD <300/1200>
    DW    STBAUD
    DB    'PARIT','Y'+80H    ; SET PARITY <EVEN/ODD/NONE>
    DW    STPAR
    DB    'CHARLE','N'+80H ; SET CHARLEN <5/6/7/8>
    DW    SETCLN
    DB    'STOPBI','T'+80H ; SET STOPBIT <1/1.5/2>
    DW    SETSB
;
     IF    DIALSET        ; (OPTIONAL)
    DB    'DIA','L'+80H    ; SET DIAL <TOUCH/PULSE>
    DW    STDIAL
     ENDIF
;

    DB    0        ; <<=== table terminator
;
;     SET <no-args>: print current statistics
;
SETSHO:
    CALL    CLS        ; Clear screen
SETSH2:
    LXI    H,SHOTBL    ; Get table of SHOW subroutines
SETSLP:    MOV    E,M        ; Get table address
    INX    H
    MOV    D,M
    INX    H
    MOV    A,D        ; End of table?
    ORA    E
    JZ    SETSHX        ; Exit if so
    PUSH    H        ; Save table pointer
    XCHG            ; Adrs to HL
    CALL    GOHL        ; Do it
    CALL    CRLF        ; Print newline
    MVI    C,CHEKCC    ; Check for console abort
    CALL    MEX
    POP    H        ; It's done
    JNZ    SETSLP        ; Continue if no abort
SETSHX:    CALL    CRLF        ; Skip a line
    RET
;
GOHL:    PCHL
;
;     table of SHOW subroutines
;
SHOTBL:    DW    BDSHOW        ; BAUD
    DW    PSHOW        ; PARITY
    DW    CLSHOW        ; CHARACTER LENGTH
    DW    SBSHOW        ; STOP BIT(S)
;
     IF    DIALSET        ; (OPTIONAL)
    DW    DISHOW        ; DIAL
     ENDIF
;
    DW    0        ; <<== table terminator
;
;     SET ?  processor
;
STHELP:    LXI    D,HLPMSG
    MVI    C,PRINT
    CALL    MEX
    RET
;
;     The help message
;
HLPMSG:    DB    CR,LF,'SET commands:',CR,LF
;
    DB    CR,LF,'SET BAUD 300 <or> 1200'
;
    DB    CR,LF,'SET PARITY EVEN <or> ODD <or> NONE'
;
    DB    CR,LF,'SET STOPBIT 1 <or> 1.5 <or> 2'
;
    DB    CR,LF,'SET CHARLEN 5 <or> 6 <or> 7 <or> 8'
;
     IF    DIALSET        ; (OPTIONAL)
    DB    CR,LF,'SET DIAL <TOUCH> or <PULSE>'
     ENDIF
;
    DB    CR,LF,LF,'$'
;
;     SET BAUD processor
;
STBAUD:    MVI    C,BDPARS    ; Function code
    CALL    MEX        ; Let MEX look up code
    JC    SETERR        ; Invalid code
    CALL    SBAUD        ; No, try to set it
    JC    SETERR        ; Not-supported code
    JMP    SETSHO        ; Review parameters
;
BDSHOW:    CALL    ILPRT        ; Display baud
    DB    'Baud rate: ',0
    LDA    MSPEED
    MVI    C,PRBAUD    ; Use MEX routine
    CALL    MEX
    RET
;
;     SET PARITY processor
;    NOTE:    Since zero is one of the valid possible values for
;        the parity bytes and the table scanning routines use
;        that as an end of table error marker, the bits of the
;        actual parity byte are "flipped" using an XOR previous
;        to searching the table for it, then flipped back before
;        updating the parity byte. Thus the values in the table
;        are one's complements or "negative logic" relative to
;        the byte saved as parity and used to set the 8251 chip.
;
STPAR:    LXI    D,PARTBL    ; Lookup next input item in table
    CALL    TSRCH
    JC    SETERR        ; If not found, error
    MOV    A,L        ; Get parity code
    XRI    11111111B    ; Flip the bits ... see note above
    STA    PARITY        ; Store it
    CALL    MODESET        ; Set parity
    JMP    SETSHO        ; Review parameters
;
PSHOW:    CALL    ILPRT        ; Show parity
    DB    'Parity:    ',0
    LXI    H,PARFND    ; Find proper message
    LDA    PARITY        ; Get parity value
    XRI    11111111B    ; Flip the bits ... see note above
    MOV    B,A        ; Second copy for SHWSCN routine
    JMP    SHWSCN        ; Goto show value scan routine
;
;     PARITY argument table
;    Table format: starting at PARFND, each entry has the one byte
;        code followed by the name string terminating with a
;        high bit set in the last character, followed by the
;        one byte code again. The last entry is followed by zero.
;    This odd format allows the table to be used for multiple purposes.
;
;    NOTE:    Since zero is one of the valid possible values for
;        the parity bytes and the table scanning routines use
;        that as an end of table error marker, the bits of the
;        actual parity byte are "flipped" using an XOR previous
;        to searching the table for it, then flipped back before
;        updating the parity byte. Thus the values in the table
;        are one's complements or "negative logic" relative to
;        the byte saved as parity and used to set the 8251 chip.
;
TPEVEN    EQU    ALLBITS-(PTYEVEN+PTYENBL) ; EVEN PARITY ENABLED (INVERSE BITS)
TPODD    EQU    ALLBITS-(PTYODD+PTYENBL) ; ODD  PARITY ENABLED (INVERSE BITS)
TPNONE    EQU    ALLBITS-(PTYDSBL) ; PARITY DISABLED     (INVERSE BITS)
;
PARFND:    DB    TPEVEN
PARTBL:    DB    'EVE','N'+80H    ; Even parity
    DB    TPEVEN,TPODD
    DB    'OD','D'+80H    ; Odd  parity
    DB    TPODD,TPNONE
    DB    'NON','E'+80H    ; No   parity
    DB    TPNONE,0
;
    DB    0        ; <<== table terminator
;
;     SET STOPBIT processor
;
SETSB:    LXI    D,SBTBL        ; Lookup next input item in table
    CALL    TSRCH
    JC    SETERR        ; If not found, error
    MOV    A,L        ; Get stopbit code
    STA    STOP        ; Store it
    CALL    MODESET        ; Set stopbit
    JMP    SETSHO        ; Review parameters
;
SBSHOW:    CALL    ILPRT        ; Show stopbit
    DB    'Stop bits: ',0
    LXI    H,SBFIND    ; Find proper message
    LDA    STOP        ; Get stopbit value
    MOV    B,A        ; Second copy for SHWSCN routine
    JMP    SHWSCN        ; Goto show value scan routine
;
;     STOPBIT argument table
;     Format of the table is identical to that of parity table
;    except that no "negative logic" is necessary or used.
;
SBFIND:    DB    STPB1
SBTBL:    DB    '1'+80H        ; One stop bit
    DB    STPB1,STPB1H
    DB    '1.','5'+80H    ; One and a half stop bits
    DB    STPB1H,STPB2
    DB    '2'+80H        ; Two stop bits
    DB    STPB2,0
;
    DB    0        ; <<== table terminator
;
;     SET CHARLEN processor
;    NOTE:    Since zero is one of the valid possible values for
;        the charlen bytes and the table scanning routines use
;        that as an end of table error marker, the bits of the
;        actual charlen byte are "flipped" using an XOR previous
;        to searching the table for it, then flipped back before
;        updating the charlen byte. Thus the values in the table
;        are one's complements or "negative logic" relative to
;        the byte saved as charlen and used to set the 8251 chip.
;
SETCLN:    LXI    D,CLNTBL    ; Lookup next input item in table
    CALL    TSRCH
    JC    SETERR        ; If not found, error
    MOV    A,L        ; Get charlen code
    XRI    11111111B    ; Flip the bits ... see note above
    STA    CHRLEN        ; Store it
    CALL    MODESET        ; Set stopbit
    JMP    SETSHO        ; Review parameters
;
CLSHOW:    CALL    ILPRT        ; Show charlen
    DB    'Char len:  ',0
    LXI    H,CLFIND    ; Find proper message
    LDA    CHRLEN        ; Get charlen value
    XRI    11111111B    ; Flip the bits ... see note above
    MOV    B,A        ; Second copy for SHWSCN routine
    JMP    SHWSCN        ; Goto show value scan routine
;
;     CHARLEN argument table
;     Format of the table is identical to that of parity table
;
;    NOTE:    Since zero is one of the valid possible values for
;        the charlen bytes and the table scanning routines use
;        that as an end of table error marker, the bits of the
;        actual charlen byte are "flipped" using an XOR previous
;        to searching the table for it, then flipped back before
;        updating the charlen byte. Thus the values in the table
;        are one's complements or "negative logic" relative to
;        the byte saved as charlen and used to set the 8251 chip.
;
TCLEN5    EQU    ALLBITS-(CHRLEN5) ; CHARACTER LENGTH = 5 (INVERSE BITS)
TCLEN6    EQU    ALLBITS-(CHRLEN6) ; CHARACTER LENGTH = 6 (INVERSE BITS)
TCLEN7    EQU    ALLBITS-(CHRLEN7) ; CHARACTER LENGTH = 7 (INVERSE BITS)
TCLEN8    EQU    ALLBITS-(CHRLEN8) ; CHARACTER LENGTH = 8 (INVERSE BITS)
;
CLFIND:    DB    TCLEN5
CLNTBL:    DB    '5'+80H        ; 5 bits
    DB    TCLEN5,TCLEN6
    DB    '6'+80H        ; 6 bits
    DB    TCLEN6,TCLEN7
    DB    '7'+80H        ; 7 bits
    DB    TCLEN7,TCLEN8
    DB    '8'+80H        ; 8 bits
    DB    TCLEN8,0
;
    DB    0        ; <<== table terminator
;
     IF    DIALSET
;
;     SET DIAL processor
;
STDIAL:    LXI    D,DIATBL    ; lookup next input item in table
    CALL    TSRCH        ; search for parameter value
    JC    SETERR        ; if not found, error
    STA    TPULSE        ; store the dial command
    JMP    SETSHO        ; review parameters
;
DISHOW:    CALL    ILPRT        ; show dial mode
    DB    'Dial:      ',0
    LDA    TPULSE        ; get dial byte
    CPI    'T'
    JZ    TTONE        ; touch tone
;
PDIAL:    CALL    ILPRT
    DB    'Pulse',0
    RET
;
TTONE:    CALL    ILPRT
    DB    'Touch Tone',0
    RET
;
;     DIAL argument table
;
DIATBL:    DB    'TOUC','H'+80H    ; touch tone
    DB    'T',0
    DB    'PULS','E'+80H    ; pulse dial
    DB    'P',0
    DB    0        ; <<=== table terminator
     ENDIF
;
;    Show set value scan routine
;
SHWSCN:    MOV    A,M        ; See if parity value matches
    ORA    A        ; First see if zero
    JZ    SETERR        ; Should never get here
    CMP    B        ; Match?
    INX    H        ; Point to first letter of message
    JZ    CDISP        ; Matches, type message
FNDNXT:    MOV    A,M
    ORA    A        ; See if end of last message
    INX    H
    JP    FNDNXT        ; Not finished
    INX    H        ; Increment past parity byte
    JMP    SHWSCN
;
;      Print message ending with 80H bit set
;
CDISP:    MOV    A,M        ; Get character to print
    INX    H        ; Point to next character
    PUSH    PSW        ; Save 80H bit
    ANI    7FH        ; Strip 80H bit just in case
    CALL    TYPE
    POP    PSW
    ORA    A
;------    JP    M,CRLF        ; Finished
    RM            ; Finished
    JMP    CDISP
;
;     Compare next input-stream item in table @DE; CY=1
;     if not found, else HL=matched data item
;
TSRCH:    MVI    C,LOOKUP    ; Get function code
    JMP    MEX        ; Pass to MEX processor
;
;     Print in-line message ... blows away C register
;
ILPRT:    MVI    C,ILP        ; Get function code
    JMP    MEX        ; Go do it
;
;     End of Sanyo MBC-1200/1250 MEX modem overlay
;
;____________________________________________________________________________
;
    END