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Text File | 1994-09-02 | 22.1 KB | 781 lines

.Z80 ASEG ; MXO-AMxx.ASM ; MEX overlay for the Ampro Little Board Computer ; Version 1.2: 23 Jul 1988 ; added routine to allow this overlay to find original ; bios under manually installed or nz-com system. ; al grabauskas ; Version 1.1: 1 Oct 1986 ; ( added support for dropping DTR for those modems that ; support it. -Marc Wilson ) ; ; Version 1.0: 28 Nov 1984 REV EQU 12 ; Overlay revision level ; This is a MEX overlay file for the Ampro Computer. It is designed ; to work with the modem connected to serial port 'B'. It also ; requires the CTC and SIO parameter tables at the front of the ; Ampro bios, as well as the I/O initialization routine in the ; Ampro bios. This is a non-standard bios call and if not present ; in the bios it must be duplicated in this overlay. ; Note that all overlays may freely use memory up to 0CFFH. If the ; overlay must work with the MEX Smartmodem overlay (MXO-SMxx.ASM), ; the physical modem overlay should terminate by 0AFFH. ;------------------------------------------------------------ ; Misc equates NO EQU 0 YES EQU 0FFH TPA EQU 100H CR EQU 13 LF EQU 10 TAB EQU 9 ; Ampro definitions IOINT EQU 57 ; BIOS call of initialization routine SIOB EQU 52H ; Relative location in bios SIOB1 EQU 53H SIOB3 EQU 55H SIOB5 EQU 57H CT1 EQU 42H ; port definitions MODCTL EQU 8CH ; Modem control port B MODDAT EQU 88H ; Modem data port B ; bit definitions MDRCVB EQU 01H ; Modem receive bit (DAV) MDRCVR EQU 01H ; Modem receive ready MDSNDB EQU 04H ; Modem send bit MDSNDR EQU 04H ; Modem send ready bit ; 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. MEX EQU 0D00H ; Address of the service processor 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 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 \ / These 2 locations are not SMODEM: DB YES ; Yes=Smartmodem / \ referenced by MEX TPULSE: DB 'T' ; T=touch, P=pulse (not referenced by MEX) CLOCK: DB 40 ; Clock speed x .1, up to 25.5 mhz. MSPEED: DB 1 ; Sets display time for sending a file ; 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 YES ; 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 YES ; 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 ; Make addresses right ; 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) INCTL1: IN A,(MODCTL) ; In modem control port RET DB 0,0,0,0,0,0,0 ; Spares if needed for non-PMMI OTDATA: OUT (MODDAT),A ; Out modem data port RET DB 0,0,0,0,0,0,0 ; Spares if needed for non=PMMI INPORT: IN A,(MODDAT) ; In modem data port RET DB 0,0,0,0,0,0,0 ; Spares if needed for non-PMMI ; Bit-test routines. These will be merged with the above ; routines in MEX 2.0 to provide a more reasonable format MASKR: AND MDRCVB RET ; Bit to test for receive ready TESTR: CP MDRCVR RET ; Value of receive bit when ready MASKS: AND MDSNDB RET ; Bit to test for send ready TESTS: CP MDSNDR RET ; Value of send bit when ready ; 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. Thus, if your modem can't dial, change the ; JMP PDIAL at DIALV to DS 3, and MEX will print a "not-implemented" ; diagnostic for any commands that require dialing. ; DIALV dials the digit in A. See the comments at PDIAL for specs. ; DISCV disconnects the modem ; GOODBV is called just before MEX exits to CP/M. If your overlay ; requires some exit cleanup, do it here. ; INMODV is called when MEX starts up; use INMODV to initialize the modem. ; NEWBDV is used for phone-number baud rates and is called with a baud-rate ; code in the A register, value as follows: ; 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 ; If your overlay supports the passed baud rate, it should store the ; value passed in A at MSPEED (107H), and set the requested rate. If ; the value passed is not supported, you should simply return (with- ; out modifying MSPEED) -or- optionally request a baud-rate from the ; user interactively. ; NOPARV is called at the end of each file transfer; your overlay may simply ; return here, or you may want to restore parity if you set no-parity ; in the following vector (this is the case with the PMMI overlay). ; PARITV is called at the start of each file transfer; your overlay may simply ; return here, or you may want to enable parity detection (this is the ; case with the PMMI overlay). ; SETUPV is the user-defined command ... to use this routine to build your own ; MEX command, set the variable SETFL (117H) non-zero, and add your SET ; code. You can use the routine presented in the PMMI overlay as a ; guide for parsing, table lookup, etc. ; SPMENU is provided only for MDM compatibility, and is not used by MEX 1.0 for ; any purpose (it will be gone in MEX 2). ; VERSNV is called immediately after MEX prints its sign-on message at cold ; startup -- use this to identify your overlay in the sign-on message ; (include overlay version number in the line). ; BREAKV is provided for sending a BREAK (<ESC>-B in terminal mode). If your ; modem doesn't support BREAK, or you don't care to code a BREAK rou- ; tine, you may simply execute a RET instruction. LOGON: DS 2 ; Needed for MDM compat, not ref'd by MEX DIALV: DS 3 ; Dial digit in A (see info at PDIAL) DISCV: JP HANGUP ; Disconnect the modem GOODBV: DS 3 ; Called before exit to CP/M INMODV: JP NITMOD ; Initialization. Called at cold-start NEWBDV: JP PBAUD ; Set baud rate NOPARV: JP NOPAR ; Set modem for no-parity PARITV: JP PARITY ; Set modem parity SETUPV: JP SETCMD ; SET cmd: jump to a RET if you don't write SET SPMENV: DS 3 ; Not used with MEX VERSNV: JP SYSVER ; Overlay's voice in the sign-on message BREAKV: DS 3 ; 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: LD DE,EOSMSG LD C,PRINT CALL MEX RET EOSMSG: DB 27,89,0,0,0,'$' CLS: LD DE,CLSMSG ; Null unless patched LD C,PRINT CALL MEX RET CLSMSG: DB 26,00,0,0,0,'$' NOPAR: RET PARITY: RET ;------------------------------------------------------------------ ; ; This routine sets DTR and RTS low for 1 second to disconnect the phone. ; This code comes from I2AM-1D.ASM. ; ;HANGUP: ; MVI B,'S'-40H ; X-off to stop host if needed ; CALL OUTDATA ; MVI B,1 ; Wait a moment to let it react ; MVI C,TIMER ; CALL MEX HANGUP: LD A,5 OUT (MODCTL),A ; Send to the status port LD A,068H ; Turn off DTR, RTS, send break OUT (MODCTL),A LD B,10 ; Wait 1 second LD C,TIMER CALL MEX LD A,5 OUT (MODCTL),A LD A,0EAH ; Restore normal, 8 bits, RTS on, etc. OUT (MODCTL),A RET ;------------------------------------------------------------------ NITMOD: LD A,5 ; Initialize to 1200 baud. No other ; Parameters changed... fall thru CALL GRABBIOS ; get bios address, whether nz-com ; or not. returned in "biosaddr:" PBAUD: PUSH HL ; Don't alter anybody PUSH DE PUSH BC LD E,A ; Code to DE LD D,0 LD HL,BAUDTB ; Offset into table ADD HL,DE LD A,(HL) ; Fetch code OR A ; 0? (means unsupported code) SCF ; Return error for STBAUD caller JP Z,PBEXIT ; Exit if so LD (BSAVE1),A ; Save it LD A,E ; Get speed code back LD (MSPEED),A ; Make it current LD HL,BAUDTX ; Offset into second table ADD HL,DE LD A,(HL) ; Get second value LD (BSAVE2),A ; Save it also LD HL,(BIOSADDR) ; Get location of bios LD L,CT1 ; Add 42 to reach CT1 in i/o table LD A,47H LD (HL),A INC HL ; Move to next location LD A,(BSAVE1) ; Get first table value LD (HL),A ; Store it LD A,(BSAVE2) ; Get second table value LD B,A ; And save it LD L,SIOB1 ; Move ahead to siob+1 values LD A,(HL) ; Get current value AND 3FH OR B ; Or it with second value LD (HL),A ; Store it in work table INC HL INC HL LD A,(HL) ; Get last value and make OR 80H ; Sure msb is set LD (HL),A ; Put it back in working table CALL IOINIT ; Do the initialization SCF CCF ; Return no error for STBAUD PBEXIT: POP BC ; All done POP DE POP HL RET IOINIT: LD A,IOINT ; Offset into bios jump table LD HL,(BIOSADDR) ; Address of bios in HL LD L,A ; Add offset JP GOHL ; And go there with auto return ; table of baud rate divisors for supported rates BAUDTB: DB 0,208,139,208,0,104 ; 110,300,450,600,710,1200 DB 52,26,13,0 ; 2400,4800,9600,19200 BAUDTX: DB 0,80H,80H,40H,0,40H DB 40H,40H,40H,0 BSAVE1: DB 0 ; Current setting from BSAVE2: DB 0 ; Tables - uninitialized ; Sign-on message SYSVER: LD DE,SOMESG LD C,PRINT CALL MEX RET SOMESG: DB 'Ampro Overlay Version ' DB REV/10+'0' DB '.' DB REV MOD 10+'0' DB ' (nz-com compatible)' DB CR,LF,'$' ; Newline on console CRLF: LD A,CR CALL TYPE LD A,LF ; Fall into TYPE ; type char in A on console TYPE: PUSH HL ; Save 'em PUSH DE PUSH BC LD E,A ; Align output character LD C,CONOUT ; Print via MEX CALL MEX POP BC POP DE POP HL RET ; Data area ;------------------------------------------------------------ ; The remainder of this overlay implements a very versatile ; SET command -- if you prefer not to write a SET for your ; modem, you may delete the code from here to the END statement. ; Control is passed here after MEX parses a SET command. SETCMD: LD C,SBLANK ; Any arguments? CALL MEX JP C,SETSHO ; If not, go print out values LD DE,CMDTBL ; Parse command CALL TSRCH ; From table PUSH HL ; Any address on stack RET NC ; If we have one, execute it POP HL ; Nope, fix stack SETERR: LD DE,SETEMS ; Print error LD C,PRINT CALL MEX RET SETEMS: DB CR,LF,'SET command error',CR,LF,'$' ; 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" DW STBAUD DB 'BIT','S'+80H ; "set bits" DW STBITS DB 'PARIT','Y'+80H ; "set parity" DW STPAR DB 'STO','P'+80H ; "set stop" DW STSTOP DB 'SHAK','E'+80H ; "set shake" DW STSHAK DB 0 ; <<=== table terminator ; SET <no-args>: print current statistics SETSHO: LD HL,SHOTBL ; Get table of SHOW subroutines SETSLP: LD E,(HL) ; Get table address INC HL LD D,(HL) INC HL LD A,D ; End of table? OR E RET Z ; Exit if so PUSH HL ; Save table pointer EX DE,HL ; Adrs to HL CALL GOHL ; Do it CALL CRLF ; Print newline LD C,CHEKCC ; Check for console abort CALL MEX POP HL ; It's done JP NZ,SETSLP ; Continue if no abort RET GOHL: JP (HL) ; table of SHOW subroutines SHOTBL: DW BDSHOW DW BITSH DW PARSH DW STPSH DW SHKSH DW 0 ; <<== table terminator ; SET ? processor STHELP: LD DE,HLPMSG LD C,PRINT CALL MEX RET ; The help message HLPMSG: DB CR,LF,'SET command, Ampro version:',CR,LF DB CR,LF,' >SET BAUD 300, 450, 600, 1200, 2400, 4800, or 9600.' DB CR,LF,' >SET BITS 5, 6, 7, or 8.' DB CR,LF,' >SET PARITY ODD, EVEN, or NONE.' DB CR,LF,' >SET STOP 1, or 2.' DB CR,LF,' >SET SHAKE ON, or OFF.' DB CR,LF,CR,LF,'$' ; SET BAUD processor STBAUD: LD C,BDPARS ; Function code CALL MEX ; Let MEX look up code JP C,SETERR ; Invalid code CALL PBAUD ; No, try to set it JP C,SETERR ; Not-supported code BDSHOW: CALL ILPRT ; Display baud DB ' Baud rate: ',0 LD A,(MSPEED) LD C,PRBAUD ; Use MEX routine CALL MEX RET ; SET BITS processor STBITS: LD DE,BITTBL ; Load lookup table CALL TSRCH ; Look for 7 or 8 JP C,SETERR ; If not found LD C,L ; Save selection value LD HL,(BIOSADDR) ; Get bios address LD L,SIOB3 ; Move to siob+3 LD A,(HL) ; Wr5 info AND 9FH ; Mask OR C ; Add selection LD (HL),A ; Store it LD A,C ; Get selection RLA LD C,A ; Shift selection left LD L,SIOB5 ; Move to siob+5 LD A,(HL) ; Wr3 info AND 3FH ; Mask OR C LD (HL),A ; Store it CALL IOINIT ; Do it. BITSH: CALL ILPRT DB ' Data bits: ',0 LD HL,(BIOSADDR) ; Get bios location LD L,SIOB3 ; Move to siob+3 LD A,(HL) ; Get current value AND 60H CP 60H JP Z,BITSH8 CP 20H JP Z,BITSH7 CP 40H JP Z,BITSH6 CALL ILPRT DB '5',0 ; Show a 5 RET BITSH6: CALL ILPRT DB '6',0 ; Show a 6 RET BITSH7: CALL ILPRT DB '7',0 ; Show a 7 RET BITSH8: CALL ILPRT DB '8',0 RET BITTBL: DB '5'+80H DW 00H DB '6'+80H DW 40H DB '7'+80H DW 20H DB '8'+80H DW 60H DB 0 ; STPAR: LD DE,PARTBL CALL TSRCH JP C,SETERR LD C,L LD HL,(BIOSADDR) ; Get bios address LD L,SIOB1 ; Go to siob+1 LD A,(HL) AND 0FCH OR C LD (HL),A CALL IOINIT PARSH: CALL ILPRT DB ' Parity: ',0 LD HL,(BIOSADDR) ; Get bios address LD L,SIOB1 LD A,(HL) AND 03H ; Mask CP 01H ; Check for none JP Z,PARSHO CP 03H JP Z,PARSHE CALL ILPRT DB 'none',0 RET PARSHO: CALL ILPRT DB 'odd',0 RET PARSHE: CALL ILPRT DB 'even',0 RET PARTBL: DB 'OD','D'+80H DW 01H DB 'EVE','N'+80H DW 03H DB 'NON','E'+80H DW 00H DB 0 STSTOP: LD DE,STPTBL CALL TSRCH JP C,SETERR LD C,L LD HL,(BIOSADDR) ; Get bios address LD L,53H ; Shift to bios+1 LD A,(HL) AND 0F3H OR C LD (HL),A CALL IOINIT STPSH: CALL ILPRT DB ' Stop bits: ',0 LD HL,(BIOSADDR) ; Get bios address LD L,53H ; Shift to bios+1 LD A,(HL) AND 0CH CP 0CH JP Z,STPSH2 CALL ILPRT DB '1',0 RET STPSH2: CALL ILPRT DB '2',0 RET STPTBL: DB '1'+80H DW 04H DB '2'+80H DW 0CH DB 0 STSHAK: LD DE,SHKTBL ; Get handshake table CALL TSRCH ; Search it for parameter JP C,SETERR ; If not found LD C,L ; Temp store value in C LD HL,(BIOSADDR) ; Get location of BIOS LD L,6DH ; Location of HSB in bios LD (HL),C ; Put new value in it SHKSH: CALL ILPRT DB ' Hand Shake: ',0 LD HL,(BIOSADDR) ; Get bios location LD L,6DH ; Location of HSB in bios LD A,(HL) ; Get current value CP 1 JP Z,SHKSHY ; Show a yes CALL ILPRT DB 'off',0 RET SHKSHY: CALL ILPRT DB 'on',0 RET SHKTBL: DB 'OF','F'+80H DW 0 DB 'O','N'+80H DW 1 DB 0 ;---------------------------------------------------------- ; Compare next input-stream item in table @DE; CY=1 ; if not found, else HL=matched data item TSRCH: LD C,LOOKUP ; Get function code JP MEX ; Pass to MEX processor ; Print in-line message ... blows away C register ILPRT: LD C,ILP ; Get function code JP MEX ; Go do it ;------------------------------------------------------------ ; This is a callable routine that locates the bios address ; whether nz-com is running or not and saves it in the word ; at "biosaddr:". It gets run once at mex initialization. ; All points in the code that used to get this address from ; location one now get it from the located and saved address. GRABBIOS: PUSH HL ; save time PUSH DE PUSH BC PUSH AF LD HL,(1) ; this is SOME bios address.. LD L,5AH ; ptr to "NZ-COM" eyecatcher LD DE,NZCEYE ; ptr to another copy of it LD B,6 ; length NZCKLOOP: LD A,(DE) ; get a char CP (HL) ; compare to char at hl JR NZ,NONZC ; no nz-com INC HL ; bump ptr INC DE ; bump ptr DEC B ; decrement length JR NZ,NZCKLOOP ; repeat if apropos LD L,85H ; offset to high byte of ; the 1st auxjump ptr LD A,(HL) ; get bios page JR RETBIOS ; and return bios addr in biosaddr NONZC: LD A,(2) ; get original page number RETBIOS: LD (BIOSADDR+1),A ; save page POP AF ; restore regs POP BC POP DE POP HL RET NZCEYE: DB 'NZ-COM' ; eyecather to match BIOSADDR: DW 3 ; just need to set page ;------------------------------------------------------------ ; End of AMPRO MEX modem overlay ;------------------------------------------------------------ END