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Some reformatting

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Andrew Kesterson
2012-11-02 22:23:15 -04:00
parent 7b5d0c76e8
commit f85b5ae095
2 changed files with 22 additions and 21 deletions
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1
Makefile
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@@ -9,4 +9,5 @@ test:
.PHONY: clean .PHONY: clean
clean: clean:
rm *nes rm *nes
rm *nes.deb
rm *fns rm *fns

42
nesgame.S
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@@ -3,15 +3,15 @@
;; how many 8kB banks of CHR data, which mapper to use for bank swapping ;; how many 8kB banks of CHR data, which mapper to use for bank swapping
;; and how to perform background mirroring ;; and how to perform background mirroring
.inesprg 1 ;; 1x 16kB bank of PRG (program) code .inesprg 1 ;; 1x 16kB bank of PRG (program) code
.ineschr 1 ;; 1x 8kB bank of CHR (tile/sprite) data .ineschr 1 ;; 1x 8kB bank of CHR (tile/sprite) data
.inesmap 0 ;; use mapper 0; NROM, no bank swapping .inesmap 0 ;; use mapper 0; NROM, no bank swapping
.inesmir 1 ;; background mirroring (we don't care for now) .inesmir 1 ;; background mirroring (we don't care for now)
;; For NESASM, we need to tell it where each bank begins. ;; For NESASM, we need to tell it where each bank begins.
.bank 0 .bank 0
.org $C000 ;; PRG bank 1 has 8kB at 0x0C000 .org $C000 ;; PRG bank 1 has 8kB at 0x0C000
;; START will be called by the NES whenever the system boots ;; START will be called by the NES whenever the system boots
;; or when the reset button is pressed (think of _start in libc ) ;; or when the reset button is pressed (think of _start in libc )
@@ -101,24 +101,24 @@ _MAIN_loop:
NMI: NMI:
RTI ; just return RTI ; just return
.bank 1 ;; NESASM sees our 16kB code banks as pairs of .bank 1 ;; NESASM sees our 16kB code banks as pairs of
.org $E000 ;; 8kB code banks, so we have to declare each .org $E000 ;; 8kB code banks, so we have to declare each
;; 8kB half-bank separately, and split code ;; 8kB half-bank separately, and split code
;; between them. ;; between them.
;; .. How to know when we have written enough ;; .. How to know when we have written enough
;; code? .. ;; code? ..
;; insert the rest of the bank 1 code here ;; insert the rest of the bank 1 code here
.bank 1 .bank 1
.org $FFFA .org $FFFA
.dw NMI ;; For Non-Maskable Interrupts, please jump to the location .dw NMI ;; For Non-Maskable Interrupts, please jump to the location
;; of the NMI label ;; of the NMI label
.dw START ;; For the reset button or power-on, jump to the location .dw START ;; For the reset button or power-on, jump to the location
;; of the START label ;; of the START label
.dw 0 ;; If we used an external IRQ vector, we would put it here .dw 0 ;; If we used an external IRQ vector, we would put it here
;; --- graphics bank ;; --- graphics bank
.bank 2 ;; CHR bank 0 starts here for tile/sprite data .bank 2 ;; CHR bank 0 starts here for tile/sprite data
.org $0000 ;; CHR data is below PRG data in the memory .org $0000 ;; CHR data is below PRG data in the memory