The Entry Address Of The Bios Subroutines - Epson PX-8 User Manual

5.7 The Entry Address of the BIOS Subroutines
Table 5.3 lists the entry addresses of BIOS subroutines.
Since the BIOS routines are relocatable, the entry addresses of BIOS subrou-
tines are indicated relative to the warm boot routine (WBOOT) address. The
WBOOT address can be found from locations 0001 and 0002 in page zero.
Table 5.3
ADDRESS ENTRY NAME ADDRESS ENTRY NAME
WBOOT -03H
BOOT
+4SH
RSIN
WBOOT WBOOT +48H RSOUT
WBOOT +03H CONST +4BH TIMDAT
+06H CONIN +4EH MEMORY
+09H CONOUT
+SlH RSIOX
+OCH LIST
+S4H
LIGHTPEN
+OFH PUNCH
+S7H
MASKI
+12H READER
+SAH LOADX
+lSH HOME
+SDH STORX
+18H SELDSK +60H LDIRX
+lBH SETTRK
+63H JUMPX
+lEH SETSEC
+66H CALLX
+21H SETDMA
+69H GETPFK
+24H READ
+6CH PUTPFK
+27H WRITE
+6FH ADCVRT
+2AH LISTST
+72H SLAVE
+2DH SECTRAN
+30H PSET
+7SH
RDVRAM
+78H MCMTX
+33H SCRNDUMP +7BH POWEROFF
+36H BEEP +7EH USERBIOS
+39H RSOPEN
+3CH RSCLOSE
+3FH RSINST
+42H RSOUTST
5.7.1 Functions of BIOS Subroutines
In the following explanations, entry parameters are those which must be as-
signed by user programs calling the BIOS routines. The contents of registers
other than those to which the system returns parameters may be changed un-
less otherwise specified.
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5.7.2 Subroutines Concerned With Power-Up and Initialization
I:IeI.I.
Entry Point: WBOOT - 03H
BOOT is the entry point for the cold start loader, which runs only when system
initialization is made or the 7508 sub-CPU is reset or
I
SHIFT
1+
IG~'i~1
keys
are pressed together with RESET switch. This routine is not used by the user.
1'·9:'·1.1.
Entry Point: See locations 000IH and 0002H in page zero.
The WBOOT location is used as the point from which all other BIOS routines
are given in the following sections. WBOOT can alter if the configuration of
the system changes, e.g. the RAM Disk size alters or the USER BIOS size
changes.
WBOOT is the entry point for the warm start bootstrap; this routine loads CCP
and BDOS into memory. The MENU or CCP module is activated after a warm
start.
Return Parameters:
The currently selected drive is returned in register C.
I
a"'ilIiI
3., ••
Entry Point: WBOOT
+
7BH
POWEROFF is the entry point for the subroutine which turns off the main
system power supply, after saving the current status.
Entry parameters
Register C
=
DOH Sets continue mode when switching on.
Register C
=
01H Sets restart mode upon power-up.
5.7.3 BIOS Subroutines for use with the console
18.,§.-,.
Entry Point: WBOOT
+
03H
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