This is a partial listing of functions provided by various CP/M 3 RSXs. The general format of a call is:
LD C,3Ch LD DE,RSXPB CALL 5 ... RSXPPB: DEFB subfun ;subfunction DEFB nppars ;number of parameters DEFW param1 ;16-bit parameters DEFW param2 ...
Subfunctions 0-7Fh can be used by user programs; Subfunctions 80h-0FFh are reserved for CP/M. If an RSX call is made and the RSX is not present, the BDOS returns BA=HL=00FFh.
Entered with subfun=0. No parameter checking.
This is used by Digital Research Logo to initialise the RSX containing device-dependent code.
ANSIRSX provides ANSI terminal emulation on Amstrad PCW computers.
Entered with subfun=1, nppars=1, param1=address of
copy of RSX name ( DEFB 'ANSIRSX' )
Terminates the currently running RSX.
See also function 3C/7F, function 3C/7E.
Entered with subfun=4. No parameter checking.
Returns 0 if BYE is active, 0FFh otherwise.
Entered with subfun=7. No parameter checking.
Returns HL=address of MXUSR byte in BYE.
MXUSR: DB MAXUSR ; Runtime maximum user area available MXDRV: DB MAXDRV ; Runtime maximum drive available TOVAL: DB TOVALUE ; Number of mins. to wait before timeout NULLS: DB 0 ; Number of nulls afterULCSW: DB 0 ; Upper case only switch (32=upper case) LFEEDS: DB 0 ; Line feed mask (0=don't mask) WRTLOC: DB 0 ; Location RBBS pokes so BYE won't hang HARDON: DB 0FFH ; If 0, hardlog is deactivated MDMOFF: DB 0 ; If 0FFH, do not output to modem COVECT: DW 0 ; Console output vector for XMODEM DB 'BYE' ; Tells XMODEM that BYE is being used BELLON: DB 0FFH ; If 0FFH ok to send bell (Chat) to con- ; sole, 00H=belloff. This only affects ; Your initial default choice LCPTR: JMP LCDATA ; First byte is user access restrictions ; and flags while user is logged on, ; used for his total time-on after ; logoff. LCDATA is address of buffer ; For NO25TH data, NO25BF in length MXTIME: JMP RTCBUF ; First byte holds maximum time allowed ; Next 2 bytes point to the real time ; clock buffer BEEPFL: DB 0 ; Flag to enable/disable inactivity beep ; so we don't affect Zmodem transfers ; 0 = beeps enabled, 0FFH = beeps off
Entered with subfun=0Bh. No parameter checking.
Deletes any RSXs loaded below BYE.RSX.
Entered with subfun=37h. No parameter checking.
HISTRSX.RSX is a command history RSX for CP/M 3. This function
initialises it, or deletes it if it is already initialised. Returns A=0 if
the call was obeyed.
Entered with subfun=38h. No parameter checking.
This function empties the HISTRSX history buffer. It returns A=0 for success.
Entered with subfun=41h. No parameter checking.
This is used by the LBRDISK program. When it is called, if a library is mounted as a directory, its name is printed preceded by a backslash; for example:
CP/M pages
A\LIBRARY>
or
12:42 B3:UTILS\LIBRARY>
under a typical Z-system command processor.
Entered with subfun=42h. No parameter checking.
Used by CCP+ named directory system. Returns the address in HL.
Entered with RSXPB:
RSXPB: DB 65h ;Subfunction DB 2 ;2 parameters DW BYE$ DW ARG ; BYE$: DB 'BYE ' ARG: DB 0,0Initialises the BYE RSX. On return, if ARG+1 is nonzero then there is an error (it must be set to 0 on entry).
Entered with RSXPB:
RSXPB: DB 66h ;Subfunction
DB 2 ;2 parameters
DW BYE$
DW ARG
;
BYE$: DB 'BYE '
ARG: DB 0,0
Terminates the BYE RSX, thus logging the current caller out.
Entered with RSXPB as below.
The UDG.RSX functions are intended to provide a moderately portable user-defined graphic system. They come in two sets; 3C/70 and 3C/72 are designed to be identical on all systems, while 3C/71,3C/73,3C/74 and 3C/75 are for use in the construction of UDG editors and similar programs on particular computers. The RSXPB is formed:
RSXPB: DEFB 70h,2 ;2 parameters DEFW UDG$ ;Parameter 1 points to RSX name DEFW DBLOCK ;Parameter 2 points to data block UDG$: DEFB 'UDG ' DBLOCK: DEFB ascii ;Character number, 0-255 DEFB bitmap ;8 bytes; most significant bit corresponds to the ;left of the character; first byte to the top.If the computer on which UDG.RSX is running does not have 8x8 characters, the bitmap should be scaled to fit. This function returns A=0 for success.
Entered with RSXPB:
RSXPB: DEFB 71h,2 ;2 parameters
DEFW UDG$ ;Parameter 1 points to RSX name
DEFW DBLOCK ;Parameter 2 points to data block
UDG$: DEFB 'UDG '
DBLOCK: DEFB ascii ;Character number, 0-255
DEFS ? ;As much space as is necessary
This function should return the bitmap for a character in its native form. The size of the character is implementation-dependent; no scaling should be done. This function returns A=0 for success.
In the Amstrad CP/M implementation, the bitmap is 8 bytes.
Entered with RSXPB:
RSXPB: DEFB 72h,2 ;2 parameters
DEFW UDG$ ;Parameter 1 points to RSX name
DEFW DBLOCK ;Parameter 2 points to data block
UDG$: DEFB 'UDG '
DBLOCK: DEFS 8 ;Bitmap to display
This function should display an 8-byte bitmap (as in function 3C/70) without comitting it to the character set. This can be done by direct screen access or by redefinition of characters 'on-the-fly'. If the screen does not have 8x8 characters, scaling should be used. This function returns A=0 for success.
Entered with RSXPB:
RSXPB: DEFB 73h,2 ;2 parameters
DEFW UDG$ ;Parameter 1 points to RSX name
DEFW DBLOCK ;Parameter 2 points to data block
UDG$: DEFB 'UDG '
DBLOCK: DEFB ascii ;Character to redefine
DEFS ? ;New bitmap
This function is the exact converse of 3C/71. It redefines a character, with
the bitmap being supplied in the native format. This function returns A=0
for success.
In the Amstrad CP/M implementation, the native format is 8 bytes long.
Entered with RSXPB:
RSXPB: DEFB 74h,2 ;2 parameters
DEFW UDG$ ;Parameter 1 points to RSX name
DEFW DBLOCK ;Parameter 2 points to data block
UDG$: DEFB 'UDG '
DBLOCK: DEFS ? ;Bitmap to display
This function should display a version-dependent bitmap without comitting it to the character set. This can be done by direct screen access or by redefinition of characters 'on-the-fly'. This call returns A=0 for success.
In the Amstrad CP/M implementation, the native format is 8 bytes long.
Entered with RSXPB:
RSXPB: DEFB 75h,2 ;2 parameters
DEFW UDG$ ;Parameter 1 points to RSX name
DEFW fontid ;Parameter 2 = font number
UDG$: DEFB 'UDG '
On computers with multiple fonts, this is used to choose which font should be affected by the other operations. Font 0 should be the font used by a 24x80 screen. This function returns A=0 for success, or 0FEh if the number is out of range. Functions 3C/70 and 3C/72 should only be used when Font 0 is selected.
In the Amstrad implementation, the CPC and PCW only allow Font 0. On the Spectrum +3, Font 0 is the 5-bit wide character set and Font 1 is the 8-bit wide character set. Functions 3C/70 and 3C/72 scale their input bitmaps to 5x8, while the other functions do not scale.
Entered with subfun=76h, nppars=1, param1=pointer to RSX name. Returns HL=status. In the case of PIPEMGR.RSX, this call returns a bitmapped value in H:
Bit 0: stdin is redirected Bit 1: stdout is redirected Bit 2: stderr is redirected Bit 3: redirected input is coming from a pipe Bit 4: redirected output is going to a pipe
Entered with subfun=79h, nppars=1, param1=pointer to RSX name. Returns HL=0 if successful, other values if error. In the case of PIPEMGR.RSX, this call scans the command line at 0080h for redirection operations.
Entered with subfun=7Ah, nppars=1, param1=byte
PIPEMGR.RSX is an extension allowing piping and redirection of I/O from CP/M 3 programs.
Entered with subfun=7Bh, nppars=1, param1=address of RSX name. Returns HL=BCD RSX version (0100h => 1.0) or 00FFh if the RSX is not present.
Entered with subfun=7Ch. No parameter checking. Returns byte in A, EOF code in H.
PIPEMGR.RSX is an extension allowing piping and redirection of I/O from CP/M 3 programs. The EOF code in H is 0 for end of file, or 1 if the byte in A is valid.
Entered with subfun=7Dh, nppars=1, param1=byte
PIPEMGR.RSX is an extension allowing piping and redirection of I/O from CP/M 3 programs.
Entered with subfun=7Eh, nppars=1, param1=address of a copy of the RSX name.
This function and the next one are used by some of my programs when loading long-term RSXs. They avoid RSX duplication using the following system:
See also function 3C/01, function 3C/7F.
Entered with subfun=7Fh, nppars=1, param1=address of a copy of the RSX name.
See also function 3C/01, function 3C/7E.
Entered with subfun=7Fh, nppars=2, param1=address of a copy of the RSX name, param2=mode.
PEEKBDOS.RSX monitors BDOS calls and prints a listing of calls
and their parameters to the screen, printer or auxiliary device. The actual
RSX ignores the subfun value; its companion COM file sends the value
7Fh.
Entered with subfun=80h. Returns address in HL. No parameter checking.
Entered with subfun=81h. No parameter checking.
Entered with subfun=82h. Returns address in HL. No parameter checking.
The FCB is for the file containing input data; with SUBMIT, this will be the SYSIN??.$$$ file. The file may be terminated with a 0FFh byte.
FCB-4: Echo flag, 0=off, 1=on FCB-3: Display control characters 0=Y 1=N FCB-2: Used by GET ([SYSTEM]?). FCB-1: User number of input file. FCB+0: FCB for input file (no random access permitted) FCB+21h: Record pointer, 0-80h (position within current record). FCB+22h: Last character processed. FCB+23h: Program input flag. FCB+24h: 128-byte current record.
Entered with subfun=0A0h. No parameter checking.
Any resident SAVE RSX will be deactivated.
Some RSXs do not use call 3Ch. Instead, they subvert an unused BDOS function number. Here are those I know of:
Entered with C=49h, DE=parameter address.
The parameter is formed:
DEFB character_number DEFB bitmap ;8 bytes
This is used in a PCW-specific program, REDEFINE.RSX. The calls from UDG.RSX should be used in preference to this call.
Entered with C=5Ah, DE=parameter.
GETERL.RSX is an extension written by me to allow the program return code to be passed from one program to another (the conventional CP/M 3 CCP resets it to zero). The parameter is either: