; Copyright 1996 Acorn Computers Ltd
;
; Licensed under the Apache License, Version 2.0 (the "License");
; you may not use this file except in compliance with the License.
; You may obtain a copy of the License at
;
; http://www.apache.org/licenses/LICENSE-2.0
;
; Unless required by applicable law or agreed to in writing, software
; distributed under the License is distributed on an "AS IS" BASIS,
; WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
; See the License for the specific language governing permissions and
; limitations under the License.
;
; > $.Source.VduDecl
; ARTHUR OPERATING SYSTEM - Vdu Drivers
; =======================
;
; Vdu driver workspace and macro declarations
;
; Author R C Manby
; Date 5.9.86
;
GBLL ForceMark ; whether we force start of mark state
ForceMark SETL {FALSE} ; of cursor on exit from WRCH
GBLL RePlot ; Re-plot cursor after wrch
RePlot SETL {TRUE}
GBLL UseVLineOnSolidLines ; When TRUE VLine is assembled and used
UseVLineOnSolidLines SETL {TRUE} ; to plot vertical solid lines
;
; Register usage
; ==============
;
StkPtr RN 13 ;Restore on exit to keep BASIC happy!!
Link RN 14
;
; Manifest constants
; ==================
;
[ VIDC_Type = "VIDC20"
; Registers
VIDCPalAddress * &10000000 ; used in palette programming
LCDOffsetRegister0 * &30000000
LCDOffsetRegister1 * &31000000
HorizCycle * &80000000
HorizSyncWidth * &81000000
HorizBorderStart * &82000000
HorizDisplayStart * &83000000
HorizDisplayEnd * &84000000
HorizBorderEnd * &85000000
HorizCursorStart * &86000000 ; used in pointer programming
HorizInterlace * &87000000
VertiCycle * &90000000
VertiSyncWidth * &91000000 ; Needed to set up FSIZE register in IOMD
VertiBorderStart * &92000000 ; First register affected by *TV
VertiDisplayStart * &93000000
VertiDisplayEnd * &94000000
VertiBorderEnd * &95000000
VertiCursorStart * &96000000
VertiCursorEnd * &97000000 ; Last register affected by *TV
VIDCExternal * &C0000000
VIDCFSyn * &D0000000
VIDCControl * &E0000000
VIDCDataControl * &F0000000
; Pseudo-registers used to return additional information to kernel
PseudoRegister_ClockSpeed * &FC000000 ; used to indicate real VIDC rclock speed
PseudoRegister_DPMSState * &FD000000 ; used to return desired DPMS state
[ ChrontelSupport
PseudoRegister_PixelRate * &FE000000 ; used to indicate the required pixel rate
]
; Bits in VCSR, VCER
CursorSinglePanel * 0 :SHL: 13
CursorTopPanel * 1 :SHL: 13
CursorBottomPanel * 1 :SHL: 14
CursorStraddle * 3 :SHL: 13
; Bits in external register
Ext_HSYNCbits * 3 :SHL: 16
Ext_InvertHSYNC * 1 :SHL: 16
Ext_CompHSYNC * 2 :SHL: 16
Ext_InvertCompHSYNC * 3 :SHL: 16
Ext_VSYNCbits * 3 :SHL: 18
Ext_InvertVSYNC * 1 :SHL: 18
Ext_CompVSYNC * 2 :SHL: 18
Ext_InvertCompVSYNC * 3 :SHL: 18
Ext_HiResMono * 1 :SHL: 14
Ext_LCDGrey * 1 :SHL: 13
Ext_DACsOn * 1 :SHL: 12
Ext_PedsOn * 7 :SHL: 8
Ext_PedsShift * 8
Ext_ERegShift * 4
Ext_ECKOn * 1 :SHL: 2
Ext_ERegBits * 3 :SHL: 0
Ext_ERegRed * 0 :SHL: 0
Ext_ERegGreen * 1 :SHL: 0
Ext_ERegBlue * 2 :SHL: 0
Ext_ERegExt * 3 :SHL: 0 ; use this for lowest power
; Bits in Frequency Synthesizer Register
FSyn_VShift * 8
FSyn_RShift * 0
FSyn_ClearV * 1 :SHL: 15
FSyn_ForceLow * 1 :SHL: 14
FSyn_ClearR * 1 :SHL: 7
FSyn_ForceHigh * 1 :SHL: 6
FSyn_ResetValue * FSyn_ClearV :OR: FSyn_ClearR :OR: FSyn_ForceLow :OR: (63 :SHL: FSyn_RShift) :OR: (0 :SHL: FSyn_VShift) ; value to get PLL working properly
; Bits in Control Register
CR_DualPanel * 1 :SHL: 13
CR_Interlace * 1 :SHL: 12
CR_FIFOLoadShift * 8
CR_LBPP0 * 0 :SHL: 5
CR_LBPP1 * 1 :SHL: 5
CR_LBPP2 * 2 :SHL: 5
CR_LBPP3 * 3 :SHL: 5
CR_LBPP4 * 4 :SHL: 5
CR_LBPP5 * 6 :SHL: 5 ; spot the gap!
CR_PixelDivShift * 2
CR_VCLK * 0 :SHL: 0
CR_HCLK * 1 :SHL: 0
CR_RCLK * 2 :SHL: 0
; Bits in Data Control Register
DCR_VRAMOff * 0 :SHL: 18
DCR_VRAMDiv1 * 1 :SHL: 18
DCR_VRAMDiv2 * 2 :SHL: 18
DCR_VRAMDiv4 * 3 :SHL: 18
DCR_BusBits * 3 :SHL: 16
DCR_Bus31_0 * 1 :SHL: 16
DCR_Bus63_32 * 2 :SHL: 16
DCR_Bus63_0 * 3 :SHL: 16
DCR_HDis * 1 :SHL: 13
DCR_Sync * 1 :SHL: 12
DCR_HDWRShift * 0
|
; Registers
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HorizDisplayStart * &8C000000 ; used in mode change code
HorizCursorStart * &98000000 ; used in pointer programming
VertiBorderStart * &A8000000 ; First register affected by *TV
VertiDisplayStart * &AC000000
VertiCursorStart * &B8000000
VertiCursorEnd * &BC000000 ; Last register affected by *TV
SoundFrequency * &C0000000
VIDCControl * &E0000000
; Bits in control register
CR_Interlace * &40 ; 0 - no interlace, 64 - interlace
CompSync * &80 ; Controls sync signal on CS/VS pin
; 0 - output vertical sync, 128 - composite sync.
; Other bits
SupBit * &1000 ; Supremacy bit in palette
]
PhysCursorStartAdr * CursorSoundPhysRAM
; Reason codes for generalised DAG interface - independent of MEMC type
MEMCDAG_VInit * 0
MEMCDAG_VStart * 1
MEMCDAG_VEnd * 2
MEMCDAG_CInit * 3
MEMCDAG_MaxReason * 3
[ ModeSelectors
; OS_ScreenMode reason codes
ScreenModeReason_SelectMode * 0
ScreenModeReason_ReturnMode * 1
ScreenModeReason_EnumerateModes * 2
ScreenModeReason_SelectMonitorType * 3
ScreenModeReason_Limit * 4
; Mode selector format
^ 0
ModeSelector_Flags # 4 ; flags word
ModeSelector_XRes # 4 ; x-resolution in pixels
ModeSelector_YRes # 4 ; y-resolution in pixels
ModeSelector_PixelDepth # 4 ; pixel depth (=Log2BPP)
ModeSelector_FrameRate # 4 ; nominal frame rate (in Hz)
ModeSelector_ModeVars # 0 ; start of pairs of (mode var index, value)
ModeSelectorFlags_FormatMask * &FF
ModeSelectorFlags_ValidFormat * 1
ModeSelector_MaxSize * ModeSelector_ModeVars+(NumModeVars * 8)+4
; maximum size of a mode selector, with each mode variable overridden
; plus terminator on end
]
;
; Macro Definitions
; =================
;
;
; Macro Sort - Sort two values into increasing order
;
MACRO
Sort $lo, $hi
CMP $hi, $lo
EORLT $lo, $lo, $hi
EORLT $hi, $lo, $hi
EORLT $lo, $lo, $hi
MEND
;
; Macro SortT - Sort two values into increasing order using a temporary reg
;
MACRO
SortT $lo, $hi, $temp
SUBS $temp, $hi, $lo
MOVLT $hi, $lo
ADDLT $lo, $lo, $temp
MEND
;
; Macro CompSwap - Compare and sort a pair of coordinates into
; order of increasing Y
; If Y values equal, sort in order of decreasing X
;
MACRO
CompSwap $xl,$yl, $xh,$yh
CMP $yh, $yl
EORLT $yl, $yl, $yh
EORLT $yh, $yl, $yh
EORLT $yl, $yl, $yh
CMPEQ $xl, $xh
EORLT $xl, $xl, $xh
EORLT $xh, $xl, $xh
EORLT $xl, $xl, $xh
MEND
;
; Macro CompSwapT - Compare and sort a pair of coordinates into
; order of increasing Y
; If Y values equal, sort in order of decreasing X
; Uses a temporary register
;
MACRO
CompSwapT $xl,$yl, $xh,$yh, $temp
SortT $yl, $yh, $temp
CMPEQ $xl, $xh
EORLT $xl, $xl, $xh
EORLT $xh, $xl, $xh
EORLT $xl, $xl, $xh
MEND
;
; Macro Difference - rc := ABS(ra-rb)
;
; Test GE/LT for ra>=rb / ra<rb
;
MACRO
Difference $rc,$ra,$rb
SUBS $rc,$ra,$rb
RSBLT $rc,$rc,#0
MEND
;
; Macro Least - Select the smallest value (signed)
;
MACRO
Least $rc,$ra,$rb
CMP $ra,$rb
[ $rc = $ra
|
MOVLE $rc,$ra
]
[ $rc = $rb
|
MOVGT $rc,$rb
]
MEND
;
; Macro Greatest - Select the largest (signed) value
;
MACRO
Greatest $rc,$ra,$rb
CMP $ra,$rb
[ $rc = $ra
|
MOVGE $rc,$ra
]
[ $rc = $rb
|
MOVLT $rc,$rb
]
MEND
;
; Macro PackXtnd - pack 2 bytes into 1 word and sign extend
;
MACRO
PackXtnd $result,$hi,$lo
[ $lo = $result
ADD $result,$lo,$hi,LSL #8
MOV $result,$result,LSL #16
MOV $result,$result,ASR #16
|
MOV $result,$hi,LSL #24
ORR $result,$lo,$result,ASR #16
]
MEND
MACRO
LoadCoordPair $x, $y, $basereg, $offset
ASSERT $x < $y
[ ($offset) :AND: 3 = 2
ADD $x, $basereg, #($offset)-2
LDMIA $x, {$x, $y} ; (Xh,Xl,??,??) (??,??,Yh,Yl)
MOV $x, $x, ASR #16 ; (Xs,Xs,Xh,Xl)
MOV $y, $y, LSL #16 ; (Yh,Yl, 0, 0)
MOV $y, $y, ASR #16 ; (Ys,Ys,Yh,Yl)
|
[ ($offset) :AND: 3 = 0
LDR $x, [$basereg, #$offset] ; (Yh,Yl,Xh,Xl)
|
[ ($offset) :AND: 3 = 1
ADD $x, $basereg, #($offset)-1
LDMIA $x, {$x, $y} ; (Yl,Xh,Xl,??) (??,??,??,Yh)
MOV $x, $x, LSR #8 ; ( 0,Yl,Xh,Xl)
ORR $x, $x, $y, LSL #24 ; (Yh,Yl,Xh,Xl)
|
ADD $x, $basereg, #($offset)-3
LDMIA $x, {$x, $y} ; (Xl,??,??,??) (??,Yh,Yl,Xh)
MOV $x, $x, LSR #24 ; ( 0, 0, 0,Xl)
ORR $x, $x, $y, LSL #8 ; (Yh,Yl,Xh,Xl)
]
]
MOV $y, $x, ASR #16 ; (Ys,Ys,Yh,Yl)
MOV $x, $x, LSL #16 ; (Xh,Xl, 0, 0)
MOV $x, $x, ASR #16 ; (Xs,Xs,Xh,Xl)
]
MEND
;
; Macro SaveRetAdr - Push R14 to our pseudo stack
;
MACRO
SaveRetAdr
Push R14
MEND
;
; Macro Return - Pull from stack into PC
;
MACRO
Return $cond
LDM$cond.FD StkPtr!, {PC}
MEND
;
; Macro SuperMode - Set supervisor mode
;
MACRO
SuperMode
SWI &16
MEND
;
; Macro UserMode - Return to user mode
;
MACRO
UserMode
TEQP PC,#0 ; Return to user mode
MOV R0,R0 ; Force a NOP so it works
MEND
;
; Macro WINDow - Compare coordinate against graphics window
;
; Test GE/LT for within/outside window
;
MACRO
WINDow $rx,$ry, $rl,$rb,$rr,$rt
; ASSERT ($rl < $rb) AND ($rb < $rr) AND ($rr < $rt)
ADD $rt,WsPtr,#GWLCol
LDMIA $rt,{$rl,$rb,$rr,$rt}
CMP $rx,$rl
CMPGE $rr,$rx
CMPGE $ry,$rb
CMPGE $rt,$ry
MEND
;
; Macro WindowRes - Window a coordinate, giving status word
;
; Result word is as follows:
;
; | |
; 1001 | 1000 | 1010
; | |
; -----+------+----- GWTRow
; | |
; 0001 | 0000 | 0010
; | |
; -----+------+----- GWBRow
; | |
; 0101 | 0100 | 0110
; | |
;
; GWLCol GWRCol
;
;
MACRO
WindowRes $result, $rx,$ry, $rl,$rb,$rr,$rt
; ASSERT ($rl < $rb) AND ($rb < $rr) AND ($rr < $rt)
MOV $result,#0
ADD $rt,WsPtr,#GWLCol
LDMIA $rt,{$rl,$rb,$rr,$rt}
CMP $rx,$rl
ORRLT $result,$result,#1 ;Set bit 0 if X < window
CMP $rr,$rx
ORRLT $result,$result,#2 ;Set bit 1 if X > window
CMP $ry,$rb
ORRLT $result,$result,#4 ;Set bit 2 if Y < window
CMP $rt,$ry
ORRLT $result,$result,#8 ;Set bit 3 if Y > window
MEND
MACRO
$lab EQUB $var
ASSERT $var >= &00
ASSERT $var <= &FF
$lab = $var
MEND
MACRO
OrrEor $d,$s, $or,$eor
ORR $d,$s,$or
EOR $d,$d,$eor
MEND
MACRO ;Scr:=ScrOR(oraANDmsk)EOR(eorANDmsk)
OrrEorMASK $scr,$msk, $ora,$eor, $tmp
AND $tmp,$msk,$ora
ORR $scr,$scr,$tmp
AND $tmp,$msk,$eor
EOR $scr,$scr,$tmp
MEND
MACRO
ORoreorEORoreor $d,$s, $oo,$eo,$oe,$ee, $tmp
OrrEor $tmp,$s, $oo,$eo
ORR $d,$d,$tmp
OrrEor $tmp,$s, $oe,$ee
EOR $d,$d,$tmp
MEND
MACRO
ORoreorEORoreorMASK $d,$s,$m, $oo,$eo,$oe,$ee, $tmp
OrrEor $tmp,$s, $oo,$eo
AND $tmp,$tmp,$m
ORR $d,$d,$tmp
OrrEor $tmp,$s, $oe,$ee
AND $tmp,$tmp,$m
EOR $d,$d,$tmp
MEND
MACRO
ShiftR $d,$e, $r,$rcomp
MOV $d,$d,LSR $r
ORR $d,$d,$e,LSL $rcomp
MEND
MACRO
ShiftL $d,$e, $r,$rcomp
MOV $e,$e,LSL $rcomp
ORR $e,$e,$d,LSR $r
MEND
MACRO
BitLOffset $b,$x, $xshftfactor,$npix,$log2bpc
AND $b,$x,$npix
MOV $b,$b,LSL $log2bpc
MEND
MACRO
BitROffset $b,$x, $xshftfactor,$npix,$log2bpc
AND $b,$x,$npix
ADD $b,$b,#1
MOV $b,$b,LSL $log2bpc
SUB $b,$b,#1
MEND
MACRO
WordOffset $w,$x, $xshftfactor,$npix,$log2bpc
MOV $w,$x,ASR $xshftfactor
MEND
MACRO
OffsetWordAndBit $o,$b,$x,$tmp
LDR $tmp,[WsPtr,#XShftFactor]
MOV $o,$x,ASR $tmp ;Word offset into scanline
LDR $tmp,[WsPtr,#NPix]
AND $b,$x,$tmp ;Pixel offset into word
LDR $tmp,[WsPtr,#Log2BPC]
MOV $b,$b,LSL $tmp ;Bit offset into word
MEND
MACRO
$label ErrorMsg $num,$string
$label DCD $num
DCB "$string", 0
ALIGN
MEND
;
; Macro when given a register will return the state to indicate
; if we are in a graphics mode. Originally lots of code used to simply
; load NPix and look for a null parameter (fair enough in 1-8 bit per pixel)
; but now we look at the mode flags, the choice of a new generation!
;
MACRO
$label GraphicsMode $scrap
$label LDR $scrap, [WsPtr, #ModeFlags]
TST $scrap, #Flag_NonGraphic ;NE then non-graphic mode!
MEND
END