a4988 wait 1ms when coming out of sleep

[WeekendWarrior1]

What does this implement/fix?

Adds a 1ms pause to the a4988 when coming out of sleep, before starting to step.

Types of changes

• Bugfix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Configuration change (this will require users to update their yaml configuraiton files to keep working)

Related issue or feature (if applicable): fixes

Pull request in esphome-docs with documentation (if applicable): esphome/esphome-docs#

Test Environment

• ESP32
• ESP8266
• Windows
• Mac OS
• Linux

Explain your changes

As specified on page 10 of the a4988 datasheet: https://www.allegromicro.com/-/media/files/datasheets/a4988-datasheet.ashx under Sleep Mode,

"When emerging from Sleep mode, in order to allow the charge pump to stabilize, provide a delay of 1 ms before issuing a Step command."

This fix adds a boolean to assist in tracking the rising edge of the sleep pin (coming out of sleep mode), and if so, adds a 1000 μs delay before continuing on with the a4988 loop.

Checklist:

• The code change is tested and works locally.
• Tests have been added to verify that the new code works (under tests/ folder).

If user exposed functionality or configuration variables are added/changed:

• Documentation added/updated in esphome-docs.

[glmnet]

Thanks