Alcor6L/eLua/spi

This module contains functions for accessing the SPI interfaces of the eLua CPU. Only master SPI mode is implemented in eLua. Functions spi.setup Setup the SPI interface clock = 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 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: nothing. spi.ssoff 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: nothing. spi.write Write one or more strings/numbers to the SPI interface. spi.write( id, data1, [data2], ..., [datan] ) id - the ID of the SPI interface. data1 - the first string/number to send. data2 (optional) - the second string/number to send. datan (optional) - the n-th string/number to send. Returns: nothing. spi.readwrite Write one or more strings/numbers to the SPI interface and return the data read from the same interface. data = spi.readwrite( id, data1, [data2], ..., [datan] ) id - the ID of the SPI interface. data1 - the first string/number to send. data2 (optional) - the second string/number to send. datan (optional) - the n-th string/number to send. Returns: data - An array with all the data read from the SPI interface.