Alcor6L/PicoLisp/spi

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Overview[edit]

This module contains functions for accessing the SPI interfaces of the Alcor6L CPU.

Only master SPI mode is implemented in eLua (and Alcor6L).

Functions[edit]

spi-setup[edit]

Setup the SPI interface

(spi-setup id type clock cpol cpha databits)
  • id - the ID of the SPI interface.
  • type - SPI interface type, can be either spi.MASTER or spi.SLAVE. NOTE: currently, only master SPI mode is supported.
  • clock - the clock of the SPI interface.
  • cpol - the clock polarity (0 or 1).
  • cpha - the clock phase (0 or 1).
  • databits - the length of the SPI data word.

Returns:

  • clock - The actual clock set on the SPI interface. Depending on the hardware, this might have a different value than the clock parameter.

spi-sson[edit]

Select the SS line (Slave Select) of the SPI interface. This is only applicable for SPI interfaces with a dedicated SS pin.

(spi-sson id)
  • id - the ID of the SPI interface.

Returns: NIL.

spi-ssoff[edit]

Deselect the SS line (Slave Select) of the SPI interface. This is only applicable for SPI interfaces with a dedicated SS pin.

(spi-ssoff id)

Arguments:

  • id - the ID of the SPI interface.

Returns: NIL.

spi-write[edit]

Write one or more strings/numbers to the SPI interface.

(spi-write id any1 [any2] ... [anyn])
  • id - the ID of the SPI interface.
  • any1 - the first symbol/number/list to send.
  • any2 (optional) - the second symbol/number/list to send.
  • anyn (optional) - the n-th symbol/number/list to send.

Returns: The last value written/passed as an argument to spi-write.

spi-readwrite[edit]

Not implemented in PicoLisp yet. See Issues on github