title 'System Control Block Definition for CP/M3 BIOS'

	public @civec, @covec, @aivec, @aovec, @lovec, @bnkbf
	public @crdma, @crdsk, @vinfo, @resel, @fx, @usrcd
        public @mltio, @ermde, @erdsk, @media, @bflgs
	public @date, @hour, @min, @sec, ?erjmp, @mxtpa


scb$base equ    0FE00H          ; Base of the SCB

@civec  equ     scb$base+22h    ; Console Input Redirection
                                ; Vector (word, r/w)
@covec  equ     scb$base+24h    ; Console Output Redirection
                                ; Vector (word, r/w)
@aivec  equ     scb$base+26h    ; Auxiliary Input Redirection
                                ; Vector (word, r/w)
@aovec  equ     scb$base+28h    ; Auxiliary Output Redirection
                                ; Vector (word, r/w)
@lovec  equ     scb$base+2Ah    ; List Output Redirection
                                ; Vector (word, r/w)
@bnkbf  equ     scb$base+35h    ; Address of 128 Byte Buffer
                                ; for Banked BIOS (word, r/o)
@crdma  equ     scb$base+3Ch    ; Current DMA Address
                                ; (word, r/o)
@crdsk  equ     scb$base+3Eh    ; Current Disk (byte, r/o)
@vinfo  equ     scb$base+3Fh    ; BDOS Variable "INFO"
                                ; (word, r/o)
@resel  equ     scb$base+41h    ; FCB Flag (byte, r/o)
@fx     equ     scb$base+43h    ; BDOS Function for Error
                                ; Messages (byte, r/o)
@usrcd  equ     scb$base+44h    ; Current User Code (byte, r/o)
@mltio	equ	scb$base+4Ah	; Current Multi-Sector Count
				; (byte,r/w)
@ermde  equ     scb$base+4Bh    ; BDOS Error Mode (byte, r/o)
@erdsk	equ	scb$base+51h	; BDOS Error Disk (byte,r/o)
@media	equ	scb$base+54h	; Set by BIOS to indicate
				; open door (byte,r/w)
@bflgs  equ     scb$base+57h    ; BDOS Message Size Flag (byte,r/o)
@date   equ     scb$base+58h    ; Date in Days Since 1 Jan 78
                                ; (word, r/w)
@hour   equ     scb$base+5Ah    ; Hour in BCD (byte, r/w)
@min    equ     scb$base+5Bh    ; Minute in BCD (byte, r/w)
@sec    equ     scb$base+5Ch    ; Second in BCD (byte, r/w)
?erjmp  equ     scb$base+5Fh    ; BDOS Error Message Jump
                                ; (word, r/w)
@mxtpa  equ     scb$base+62h    ; Top of User TPA
                                ; (address at 6,7)(word, r/o)
	end