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Prep for MBC DMA support

pull/243/head
b1ackmai1er 4 years ago
parent
5b501eb956
commit
62e2f41100
2 changed files with 37 additions and 13 deletions
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  1. 49
      Source/HBIOS/dma.asm
  2. 1
      Source/HBIOS/std.asm

49
Source/HBIOS/dma.asm
View File

@ -1,11 +1,7 @@
;==================================================================================================
; Z80 DMA DRIVER FOR ECB-DMA
; Z80 DMA DRIVER
;==================================================================================================
;
; DUE TO LOW CLOCK SPEED CONTRAINTS OF Z80 DMA CHIP, THE HALF CLOCK FACILITY
; IS USED DURING DMA PROGRAMMING AND CONTINUOUS BLOCK TRANSFERS.
; TESTING CONDUCTED ON A SBC-V2-005 @ 10Mhz
;
DMA_CONTINUOUS .equ %10111101 ; + Pulse
DMA_BYTE .equ %10011101 ; + Pulse
DMA_BURST .equ %11011101 ; + Pulse
@ -26,7 +22,19 @@ DMA_RESET .equ $c3
;DMA_ENABLE_AFTER_RETI .equ $b7
;DMA_REINIT_STATUS_BYTE .equ $8b
;
DMA_FBACK .equ TRUE
DMA_FBACK .equ TRUE ; ALLOW FALLBACK TO SOFTWARE
DMA_USEHS .equ TRUE ; USE CLOCK DIVIDER
;
#IF (DMAMODE=DMAMODE_MBC)
DMA_RDY .EQU %00000000
DMA_FORCE .EQU 1
;DMA_USEHS .SET FALSE
#ENDIF
#IF (DMAMODE=DMAMODE_ECB)
DMA_RDY .EQU %00001000
DMA_FORCE .EQU 0
DMA_USEHS .SET TRUE
#ENDIF
;
;==================================================================================================
; DMA INITIALIZATION CODE
@ -38,12 +46,14 @@ DMA_INIT:
LD A, DMABASE
CALL PRTHEXBYTE
;
xor a
LD A,DMA_FORCE
out (DMABASE+1),a ; force ready off
;
#IF (DMA_USEHS)
ld a,(HB_RTCVAL)
or %00001000 ; half
out (RTCIO),a ; clock
#ENDIF
;
call DMAProbe ; do we have a dma?
jr nz,DMA_NOTFOUND
@ -58,11 +68,13 @@ DMA_INIT:
xor a ; set status
;
DMA_EXIT:
#IF (DMA_USEHS)
push af
ld a,(HB_RTCVAL)
and %11110111 ; full
out (RTCIO),a ; clock
pop af
#ENDIF
ret
;
DMA_NOTFOUND:
@ -132,7 +144,7 @@ DMACode ;.db DMA_DISABLE ; R6-Command Disable DMA
.dw 0 ; R4-Port B, Destination address
.db %00001100 ; R4-Pulse byte follows, Pulse generated
.db 0 ; R4-Pulse offset
.db %10011010 ; R5-Stop on end of block, ce/wait multiplexed, READY active HIGH
.db %10010010+DMA_RDY; R5-Stop on end of block, ce/wait multiplexed, READY active config
.db DMA_LOAD ; R6-Command Load
; .db DMA_FORCE_READY ; R6-Command Force ready
; .db DMA_ENABLE ; R6-Command Enable DMA
@ -151,9 +163,11 @@ DMALDIR:
ld b,DMACopy_Len ; dma command
ld c,DMABASE ; block
;
#IF (DMA_USEHS)
ld a,(HB_RTCVAL)
or %00001000 ; half
out (RTCIO),a ; clock
#ENDIF
di
otir ; load and execute dma
ei
@ -163,12 +177,13 @@ DMALDIR:
in a,(DMABASE) ; set non-zero
and %00111011 ; if failed
sub %00011011
#IF (DMA_USEHS)
push af
ld a,(HB_RTCVAL)
and %11110111 ; full
out (RTCIO),a ; clock
pop af
#ENDIF
ret
;
DMACopy ;.db DMA_DISABLE ; R6-Command Disable DMA
@ -182,7 +197,7 @@ DMALength .dw 0 ; R0-Block length
DMADest .dw 0 ; R4-Port B, Destination address
.db %00001100 ; R4-Pulse byte follows, Pulse generated
.db 0 ; R4-Pulse offset
; .db %10011010 ; R5-Stop on end of block, ce/wait multiplexed, READY active HIGH
; .db %10010010+DMA_RDY;R5-Stop on end of block, ce/wait multiplexed, READY active config
.db DMA_LOAD ; R6-Command Load
.db DMA_FORCE_READY ; R6-Command Force ready
.db DMA_ENABLE ; R6-Command Enable DMA
@ -201,9 +216,11 @@ DMAOTIR:
ld b,DMAOut_Len ; dma command
ld c,DMABASE ; block
;
#IF (DMA_USEHS)
ld a,(HB_RTCVAL)
or %00001000 ; half
out (RTCIO),a ; clock
#ENDIF
di
otir ; load and execute dma
ei
@ -214,11 +231,13 @@ DMAOTIR:
and %00111011 ; if failed
sub %00011011
;
#IF (DMA_USEHS)
push af
ld a,(HB_RTCVAL)
and %11110111 ; full
out (RTCIO),a ; clock
pop af
#ENDIF
ret
;
DMAOutCode ;.db DMA_DISABLE ; R6-Command Disable DMA
@ -235,7 +254,7 @@ DMAOutDest .db 0 ; R4-Port B, Destination port
; .db %00001100 ; R4-Pulse byte follows, Pulse generated
; .db 0 ; R4-Pulse offset
.db %10011010 ; R5-Stop on end of block, ce/wait multiplexed, READY active HIGH
.db %10010010+DMA_RDY;R5-Stop on end of block, ce/wait multiplexed, READY active config
.db DMA_LOAD ; R6-Command Load
.db %00000101 ; R0-Port A is Source
.db DMA_LOAD ; R6-Command Load
@ -256,9 +275,11 @@ DMAINIR:
ld b,DMAIn_Len ; dma command
ld c,DMABASE ; block
;
#IF (DMA_USEHS)
ld a,(HB_RTCVAL)
or %00001000 ; half
out (RTCIO),a ; clock
#ENDIF
di
otir ; load and execute dma
ei
@ -269,11 +290,13 @@ DMAINIR:
and %00111011 ; if failed
sub %00011011
;
#IF (DMA_USEHS)
push af
ld a,(HB_RTCVAL)
and %11110111 ; full
out (RTCIO),a ; clock
pop af
#ENDIF
ret
;
DMAInCode ;.db DMA_DISABLE ; R6-Command Disable DMA
@ -287,7 +310,7 @@ DMAInLength .dw 0 ; R0-Block length
DMAInSource .db 0 ; R4-Port B, Destination port
; .db %00001100 ; R4-Pulse byte follows, Pulse generated
; .db 0 ; R4-Pulse offset
.db %10011010 ; R5-Stop on end of block, ce/wait multiplexed, READY active HIGH
.db %10010010+DMA_RDY;R5-Stop on end of block, ce/wait multiplexed, READY active config
.db DMA_LOAD ; R6-Command Load
.db DMA_FORCE_READY ; R6-Command Force ready
.db DMA_ENABLE ; R6-Command Enable DMA
@ -295,7 +318,7 @@ DMAInSource .db 0 ; R4-Port B, Destination port
DMAIn_Len .equ $-DMAInCode
;
;==================================================================================================
; DEBUG - READ START, DESTINATION AN COUNT REGISTERS
; DEBUG - READ START, DESTINATION AND COUNT REGISTERS
;==================================================================================================
;
#IF (0)

1
Source/HBIOS/std.asm
View File

@ -225,6 +225,7 @@ DMAMODE_ECB .EQU 1 ; ECB-DMA WOLFGANG KABATZKE'S Z80 DMA ECB BOARD
DMAMODE_Z180 .EQU 2 ; Z180 INTEGRATED DMA
DMAMODE_Z280 .EQU 3 ; Z280 INTEGRATED DMA
DMAMODE_RC .EQU 4 ; RC2014 Z80 DMA
DMAMODE_MBC .EQU 5 ; MBC
;
; SERIAL DEVICE CONFIGURATION CONSTANTS
;

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