Use CONFIG_MACH_AVR instead of CONFIG_CLOCK_FREQ to check for slow
mcus. Some fast MCUs do not export a high clock frequency.
Signed-off-by: Kevin O'Connor <kevin@koconnor.net>
Add a helper function to convert from a string buffer passed in the
args[] parameter to an actual pointer. This avoids all the callers
needing to perfrom pointer manipulation.
Signed-off-by: Kevin O'Connor <kevin@koconnor.net>
On fast MCUs (like the SAMD51) it is possible for the gpio to toggle
faster than the st7920 can accept. Add a small delay around the clock
rise signal.
Signed-off-by: Lars R. Hansen <popshansen@hotmail.com>
Signed-off-by: Kevin O'Connor <kevin@koconnor.net>
It appears the st7920 requires a longer delay when switching from
command to data mode (and vice-versa). Slower MCUs don't show a
problem because the klipper command processing time results in a
sufficient delay. However, some of the faster MCUs can process
klipper commands fast enough that the next st7920 transfer is sent too
fast. Add an additional delay to account for this.
Signed-off-by: Kevin O'Connor <kevin@koconnor.net>
Kevin O'Connor