The spi command

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Synopsis

spi subcommand ?arg ...?

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Description

The spi command lets you manipulate the Raspberry Pi spi interfaces. The legal values of subcommand are listed below. Note that you can abbreviate the subcommands.

spi open device

Open the spi port. This command returns a channel identifier that may be used in future invocations of the standard Tcl I/O commands like read, puts, and close.

spi transfer channelId data

Perform full duplex communication. This command transmits the specified data. At the same time it receives an equal amount of data, which is returned to the caller.

Configuration options

The chan configure command can be used to query and set several configuration options for spi channels:

-bpw bits

Set the number of bits per word.

-delay usecs

Specify the delay between two words.

-mode mode

Control the clock polarity and phase.

-speed speed

Modify the connection speed.