diff options
Diffstat (limited to 'docs/rp2/tutorial')
| -rw-r--r-- | docs/rp2/tutorial/pio.rst | 7 |
1 files changed, 5 insertions, 2 deletions
diff --git a/docs/rp2/tutorial/pio.rst b/docs/rp2/tutorial/pio.rst index 9981aed83..4e519650e 100644 --- a/docs/rp2/tutorial/pio.rst +++ b/docs/rp2/tutorial/pio.rst @@ -76,9 +76,10 @@ and state machines. Below is the code for reference. 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") @@ -113,6 +114,8 @@ the following: X starts with the value 31 this jump will happen 31 times, so the ``nop() [29]`` runs 32 times in total (note there is also one instruction cycle taken by the ``jmp`` for each of these 32 loops). +- The single ``nop()`` correlates with the cycle used for IRQ raise, and ensures + the same number of cycles are used for LED on and LED off. - ``set(pins, 0)`` will turn the LED off by setting pin 25 low. - Another 32 loops of ``nop() [29]`` and ``jmp(...)`` will execute. - Because ``wrap_target()`` and ``wrap()`` are not specified, their default will |