; AltoConsts, EmulatorDefs, R-Regs, constants and labels used in Spruce microcode
; (Orbit microcode, trident microcode, and other packages retain their own defs)

#AltoConsts23.mu;	from [*]<Altosource>AltoConsts23.mu

; from [*]<Altosource>BcplRuntimeSources.mu(EmulatorDefs.mu):
; Standard microinstruction addresses in the Rom
; (see Alto Hardware Manual, section 9.1).
; These declarations do not cause space to be allocated in the Ram
; (except TRAP1, which we presumably want to define in the Ram)

; $START		$L4020, 0, 0; placed explicitly in SpruceMc
$RAMCYCX	$L4022, 0, 0;
$BLT		$L4105, 0, 0;
$BLKS		$L4106, 0, 0;
$MUL		$L4120, 0, 0;
$DIV		$L4121, 0, 0;
$BITBLT		$L4124, 0, 0;
$L0		$L4160, 0, 0;

; !37,1, TRAP1; included in larger vector reservation in SpruceMc


; Standard R-registers usable by the emulator task

$AC3		$R0;	Accumulators
$AC2		$R1;
$AC1		$R2;
$AC0		$R3;
$NWW		$R4;	New wakeups waiting (communication between tasks)
$SAD		$R5;	Temporary private to emulator
$PC		$R6;	Program Counter for emulated Nova
$XREG		$R7;	Temporary private to emulator.
;			Contains instruction LCY 8 upon dispatch to TRAP1.
$XH		$R10;	Temporary private to emulator
$MTEMP		$R25;	Temporary usable by any task
$DWAX		$R35;	Temporary private to emulator
$MASK		$R36;	Temporary private to emulator

$LREG		$R40;	Another name for the M-register

; In addition to those described in EmulatorDefs, the following is true of R-Registers:
; 11-13	Reserved for standard I/O devices
; 14		Used by T80, could possibly be used during TASK segment
; 15-17	Available for use by RAM applications
; 20-24	Display
; 26-27	Display
; 30-34	Disk
; 35-36	BitBlt temps, in addition to other emulator uses
; 37		Almost doesn't exist, holds RTC
; 41-51	BitBlt temps

; Then there is Mesa (not relevant in Spruce, but good to know):
; 15-17	Mesa uses
; 41		"
; 44-47	"
; 51-57	"
; 60-67	The Stack!

; Reset Mode Register Update instruction, used in SpruceMc
$RMR		$L20013, 00000, 124000;		F1=13, set RMR

; Global R-register definitions, constants used throughout
$LASTL	$R40; another name for M or LREG
$temp		$R17; used as such in several routines
$170000		$170000;  used by orbit and showchar
$177026		$177026;
$EvenMask		$177776;

; LOADR, STORER instruction temps -- the instructions cannot list these registers as targets

$instr		$R10;	NOVA RamTrap instruction that caused the trap
$low		$R17;	low half of RAM instruction during its composition -- hi is in XREG

; RowRotate Registers
$INBUF	$R3	; AC0  Address preceding first of next eight words to read
$OUTBUF	$R1	; AC2  Address preceding first word to write into
$WPR		$R0	; AC3  Displacement of words, beginning with INBUF
$RCNT		$R41	; Counts number of columns left to handle	(share these with Orbit)
$INADR	$R42	; Temp during column fetching
$BITCNT	$R43	; Inner loop control
$WDCNT	$R44	; Temp during column fetching

$SHR1		$R2	; AC1  These hold one word from each of eight rows, are shifted to 
$SHR2		$R5	; SAD  produce output samples
$SHR3		$R7	; XREG
$SHR4		$R10	; XH
$SHR5		$R35	; DWAX
$SHR6		$R36	; MASK
$SHR7		$R15	; (unused in standard microcode, share with Orbit)
$SHR8		$R16	; (unused in standard microcode, share with Orbit)
$HOLD	$R17	; Holds output sample as it is developing (share with Orbit)

; TriCon defs needed outside TriConBodyMc
$EXITRAM	$L4000, 0, 0;   TriCon's name for NOVEM
 
; ShowChar registers, index definitions
; Return codes from ShowChars
;$MUDone $0;
$MUCharRange $1;
$MUCant $1;
$MUOffPage $2;
$MUBufFull $3;

$BERectangleH $1;

; Registers used by ShowChars (and FlushChars -- indented)
; Read-only values supplied at Setup time
$BandTable	$R70;
$CopyTable	$R52;
$WidthPointer	$R67;
$nVisibleBands	$R66;
$onlyOnCopy	$R65;
$ICCUses		$R64;
$ICCOffset	$R63;
$bcM1		$R62;
$ec		$R61;

; Values updated at final return
$CurS0		$R60;
$CurS1		$R57;
$CurB0		$R56;
$CurB1		$R55;
$fspn		$R16;	FontSizePageNew increment, R-Reg for clear code, below
$fspo		$R15;	FontSizePageOld increment, R-Reg for clear code, below

; Values updated on buffer-full returns
$BandFree	$R54;
	$pData	$R54; FlushChars() called while ShowChars in effect; so can only use temp regs.
$BandAvail	$R53;
	$typeWd $R53;

; Values updated on every return
$c		$R47;
	$numData $R47;
$band		$R51;
	$outAddr	$R51;

; Temporaries used during ShowChars operation
$savedPC		$R50;
$ct		$R46;
$byteIdx		$R45;
$base		$R44;
$data		$R43;
$icc		$R42;
  $entryLen	$R42; used in BandEnter, either at end of ShowChars or called directly
	$leftCt	$R42;
$p		$R41;
$uses		  $R41;
$b		$R7;
$lineBand		$R10;

;; DCS, October 20, 1978  12:00 PM, derived from other sources
;; October 23, 1978  6:51 AM, add constants, regs for FlushChars
;; k40\f0