spi_bit_bang.md

title
spi_bit_bang:

spi_bit_bang:

--8<-- "config_section.md"

Valid in
machine config files	YES ✅
mode config files	NO 🚫

The spi_bit_bang: section of your config is where you configure the How to use SPI Bit Bang in MPF platform.

Required settings

The following sections are required in the spi_bit_bang: section of your config:

clock_pin:

Single value, type: string name of a digital_outputs: device. Defaults to empty.

This output is used to clock the SPI chip.

cs_pin:

Single value, type: string name of a digital_outputs: device. Defaults to empty.

This output is used to chip select the SPI chip. It usually also triggers the parallel read of the chip.

miso_pin:

Single value, type: string name of a switches: device. Defaults to empty.

This input is read serially to determine the state of your inputs.

Optional settings

The following sections are optional in the spi_bit_bang: section of your config. (If you don't include them, the default will be used).

bit_time:

Single value, type: time string (secs) (Instructions for entering time strings). Default: 50ms

How long should the platform wait until reading the miso_pin. Depending on your platform it might need a while to settle. Especially if your platform is connected via USB. If your inputs are local (i.e. on a RPi) this might be very short compared.

clock_time:

Single value, type: time string (ms) (Instructions for entering time strings). Default: 1ms

How long should the clock pulse be? 1ms is the lower limit for most platforms and more than long enough for any chip so this should be good.

debug:

Single value, type: boolean (true/false). Default: false

Set to true to get more debug output.

inputs:

Single value, type: integer. Default: 8

How many inputs should the platform read? Reading less inputs will result in faster updates.

Related How To guides

• How to use SPI Bit Bang in MPF
• Using the Stern Spike Trough