22 lines
768 B
ArmAsm
22 lines
768 B
ArmAsm
init_addresses:
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.byte <MOCK_6522_DDRB1,<MOCK_6522_DDRA1 ; set the data direction for all pins of PortA/PortB to be output
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.byte <MOCK_6522_ACR,<MOCK_6522_IER ; Continuous interrupts, clear all interrupts
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.byte <MOCK_6522_IFR,<MOCK_6522_IER ; enable interrupt on timer overflow
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.byte <MOCK_6522_T1CL,<MOCK_6522_T1CH ; set oflow value, start counting
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.byte <MOCK_6522_ORB1,<MOCK_6522_ORB1 ; reset ay-3-8910
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; note, terminated by the $ff below
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init_values:
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.byte $ff,$ff ; set the data direction for all pins of PortA/PortB to be output
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.byte $40,$7f
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.byte $C0,$C0
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.byte $e7,$4f ; 50Hz
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.byte MOCK_AY_RESET,MOCK_AY_INACTIVE
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; c7ce / 1.023e6 = .050s, 20Hz
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; 9c40 / 1.023e6 = .040s, 25Hz
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; 4fe7 / 1.023e6 = .020s, 50Hz
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; 411a / 1.023e6 = .016s, 60Hz
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