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docs/rp2: Make LED have exactly 50% duty cycle in PIO 1Hz example.

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This ensures the same number of cycles are used for LED on and LED off in
the PIO 1Hz example.  It's also possible to swap the first set() and the
irq() to avoid using an extra instruction, but this tutorial is a good
example of how to calculate the cycles.

Signed-off-by: Stig Bjørlykke <stig@bjorlykke.org>
This commit is contained in:
Stig Bjørlykke
2022-12-15 18:32:10 +01:00
committed by Damien George
parent 5890a17ae0
commit 209a6bb6b7
2 changed files with 8 additions and 4 deletions
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5
examples/rp2/pio_1hz.py
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@@ -16,9 +16,10 @@ def blink_1hz():
nop() [29]
jmp(x_dec, "delay_high")
# Cycles: 1 + 7 + 32 * (30 + 1) = 1000
# Cycles: 1 + 1 + 6 + 32 * (30 + 1) = 1000
nop()
set(pins, 0)
set(x, 31) [6]
set(x, 31) [5]
label("delay_low")
nop() [29]
jmp(x_dec, "delay_low")