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Merge pull request #604 from blackystardust/master
Improved reu size detection.
This commit is contained in:
Bob Andrews
GitHub
commit
7e6942953c
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@ -221,10 +221,8 @@ missing on VDC, and are translated to the two colors missing from the VIC palett
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Will test the hardware for the available RAM.
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<tag><tt/c128-reu.emd (c128_reu_emd)/</tag>
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A driver for the CBM REUs. The driver will determine from the connected REU
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if it supports 128KB of RAM or more. In the latter case, 256KB are assumed,
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but since there are no range checks, the application can use more memory if
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it has better knowledge about the hardware than the driver.
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A driver for the CBM REUs. The driver will test the connected REU to find
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out how much RAM is present.
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<tag><tt/c128-vdc.emd (c128_vdc_emd)/</tag>
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A driver for the VDC memory of the C128, written and contributed by Maciej
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@ -300,10 +300,8 @@ Note that the graphics drivers are incompatible with the
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Will test the hardware for the available RAM.
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<tag><tt/c64-reu.emd (c64_reu_emd)/</tag>
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A driver for the CBM REUs. The driver will determine from the connected REU
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if it supports 128KB of RAM or more. In the latter case, 256KB are assumed,
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but since there are no range checks, the application can use more memory if
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it has better knowledge about the hardware than the driver.
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A driver for the CBM REUs. The driver will test the connected REU to find
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out how much RAM is present.
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<tag><tt/c64-vdc.emd (c64_vdc_emd)/</tag>
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A driver for the VDC memory of the C128. Written and contributed by Maciej
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@ -55,6 +55,8 @@ REU_TRIGGER = $FF00 ; REU command trigger
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OP_COPYFROM = $ED
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OP_COPYTO = $EC
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OP_COPYFROM_ALOAD = $B1
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OP_COPYTO_ALOAD = $B0
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; ------------------------------------------------------------------------
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; Data.
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@ -92,17 +94,56 @@ INSTALL:
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cmp REU_REUADDR ; Check for presence of REU
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bne nodevice
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ldy #>(128*4) ; Assume 128KB
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lda REU_STATUS
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and #$10 ; Check size bit
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beq @L1
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ldy #>(256*4) ; 256KB when size bit is set
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@L1: sty pagecount+1
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; determine the size
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php
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sei
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ldy #$FF
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sty curpage
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sty curpage+1 ; Invalidate the current page
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txa ; X = A = EM_ERR_OK
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loop:
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sty window
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jsr reu_size_check_common
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ldx #OP_COPYTO_ALOAD
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stx REU_COMMAND
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dey
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cpy #$FF
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bne loop
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iny
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size_loop:
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jsr reu_size_check_common
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ldx #OP_COPYFROM_ALOAD
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stx REU_COMMAND
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cpy window
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bne size_found
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iny
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bne size_loop
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size_found:
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plp
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ldx #$00
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cpy #$00 ; too many pages, shave off 2
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bne pagecount_ok
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dex
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dex
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dey
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pagecount_ok:
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stx pagecount
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sty pagecount+1
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lda #<EM_ERR_OK
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ldx #>EM_ERR_OK
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rts
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; common REU setup for size check
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reu_size_check_common:
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sty REU_REUADDR+2
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ldx #<window
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stx REU_C64ADDR
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ldx #>window
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stx REU_C64ADDR+1
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ldx #$00
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stx REU_REUADDR
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stx REU_REUADDR+1
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stx REU_COUNT+1
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stx REU_CONTROL
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inx
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stx REU_COUNT
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rts
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; No REU found
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@ -55,6 +55,9 @@ REU_TRIGGER = $FF00 ; REU command trigger
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OP_COPYFROM = $ED
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OP_COPYTO = $EC
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OP_COPYFROM_ALOAD = $B1
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OP_COPYTO_ALOAD = $B0
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; ------------------------------------------------------------------------
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; Data.
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@ -92,19 +95,59 @@ INSTALL:
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cmp REU_REUADDR ; Check for presence of REU
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bne nodevice
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ldy #>(128*4) ; Assume 128KB
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lda REU_STATUS
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and #$10 ; Check size bit
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beq @L1
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ldy #>(256*4) ; 256KB when size bit is set
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@L1: sty pagecount+1
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; determine the size
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php
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sei
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ldy #$FF
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sty curpage
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sty curpage+1 ; Invalidate the current page
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txa ; X = A = EM_ERR_OK
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loop:
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sty window
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jsr reu_size_check_common
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ldx #OP_COPYTO_ALOAD
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stx REU_COMMAND
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dey
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cpy #$FF
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bne loop
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iny
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size_loop:
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jsr reu_size_check_common
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ldx #OP_COPYFROM_ALOAD
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stx REU_COMMAND
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cpy window
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bne size_found
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iny
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bne size_loop
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size_found:
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plp
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ldx #$00
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cpy #$00 ; too many pages, shave off 2
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bne pagecount_ok
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dex
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dex
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dey
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pagecount_ok:
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stx pagecount
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sty pagecount+1
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lda #<EM_ERR_OK
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ldx #>EM_ERR_OK
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rts
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; common REU setup for size check
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reu_size_check_common:
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sty REU_REUADDR+2
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ldx #<window
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stx REU_C64ADDR
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ldx #>window
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stx REU_C64ADDR+1
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ldx #$00
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stx REU_REUADDR
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stx REU_REUADDR+1
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stx REU_COUNT+1
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stx REU_CONTROL
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inx
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stx REU_COUNT
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rts
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; No REU found
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nodevice:
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