31 lines
1.1 KiB
Text
31 lines
1.1 KiB
Text
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; THIS PIO PROGRAM EXPECTS THE SYSTEM CLOCK TO BE 125MHz
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; Input is a succession of optional bools: (value/do we output something)
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; This makes so we can output an arbitrary number of bits without worrying about sizes
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; Useful since the end bit makes it so the output size is always = 1 [8]
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; Clock is / 5 i.e 25MHz
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; This will crash if fed an output of len == -1 [Z/8Z]
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.program joybus ;
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public inmode: ; Code must force a jump here once it's done using the out mode
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set pindirs, 0 ;
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inagain: ;
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wait 0 pin 0 [31] ; After the instruction complete we wait 61 cycles and read on the 62th
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nop [31] ;
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in pins, 1 ;
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wait 1 pin 0 ;
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jmp inagain ;
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;
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public outmode: ; External code must force a jump here in reaction to the RX FIFO contents
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set pins, 1 ;
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set pindirs, 1 ;
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outagain: ;
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pull ifempty block ; On pull 1 et ensuite on l'utilise pour X ET Y ?
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out x, 1 ; X = what should we output
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out y, 1 ; Y = should we output something
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jmp !y inmode ; if Y 0, empty the queue
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set pins, 0 [ 24 ] ;
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mov pins, x [ 24 ] ;
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mov pins, x [ 24 ] ;
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set pins, 1 [ 19 ] ;
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jmp outagain
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