kopia lustrzana https://github.com/raspberrypi/pico-extras
35 wiersze
1.1 KiB
Plaintext
35 wiersze
1.1 KiB
Plaintext
;
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; Copyright (c) 2020 Raspberry Pi (Trading) Ltd.
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;
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; SPDX-License-Identifier: BSD-3-Clause
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;
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.program video_htiming
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.side_set 1 ; used for clock
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public entry_point:
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; todo we can do this with one off setup via pio_exec
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pull block side 0
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.wrap_target
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new_state:
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out exec, 16 side 1 ; this does any per state inline work (or it can be a JMP to entry_point to sleep..
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; note the EXECed instruction should have a side set 0
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out x, 13 side 1
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out pins, 3 side 0 ; we want an OUT EXEC above which sets an IRQ to start scanline output
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; to cause this out and the pixel out in the same cycle (this would be positive clk edge latch)
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loop:
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nop side 1
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jmp x-- loop side 0
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.wrap
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; these are the values used in the out exec in video_htiming
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.program video_htiming_states
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.side_set 1
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; state 0 = set irq 0
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irq 0 side 0
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; state 1 = set irq 1
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irq 1 side 0
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; state 2 = set irq 4
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irq 4 side 0
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; state 3 = clear irq 4
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irq clear 4 side 0
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