45 lines
1013 B
NASM
Executable File
45 lines
1013 B
NASM
Executable File
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* Hello World for TI-99/4a computer with TMS9900 CPU
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* by Frog ( http://frog.enlight.ru )
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* 15 April 2016
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*
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****************************************************************************
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DEF START
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WRKSP EQU >8300
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VDPWD EQU >8C00 * VDP RAM write data
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VDPWA EQU >8C02 * VDP RAM read/write address
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START LIMI 0 * disable interrupts
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LWPI WRKSP * set default workspace
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* set VDP RAM start address (low and high byte)
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LI R0,>0000
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ORI R0,>4000
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SWPB R0
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MOVB R0,@VDPWA
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SWPB R0
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MOVB R0,@VDPWA
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LI R1,HELLOWORLD * ascii string address
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LI R2,12 * total chars
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NEXTCHAR
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MOVB *R1+,@VDPWD * put next char on screen
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DEC R2
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JNE NEXTCHAR
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LOOPBACK
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JMP LOOPBACK * stop and do nothing
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HELLOWORLD
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TEXT 'HELLO WORLD!' * string data
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BYTE 0
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END
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