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This module provides an interface to the MCP3008 analog to digital converter with SPI interface.
It uses HiPi::Device::SPI as a backend
Returns a new instance of the HiPi::Interface::MCP3008 class. Optional key => values pairs in %params and their defaults: The parameters are all passed through to HiPi::Device::SPI devicename => '/dev/spidev0.0', speed => SPI_SPEED_MHZ_1, bitsperword => 8, delay => 0, You probably want to specify the devicename explicitly depending on which cable select pin you have connected the MCP3008 For SPI0_CEO_N my $adc = HiPi::Interface::MCP3008->new( devicename => '/dev/spidev0.0', ); For SPI0_CE1_N my $adc = HiPi::Interface::MCP3008->new( devicename => '/dev/spidev0.1', ); See Raspberry Pi GPIO Pin layout for pin locations.
$mode is the seven bit mask described as the configure bits in the MCP3008 datasheet that determines the channel and read mode for the returned value. For convenience the module exports the following constants that you can pass as a value for $mode MCP3008_S0 # single-ended CH0 MCP3008_S1 # single-ended CH1 MCP3008_S2 # single-ended CH2 MCP3008_S3 # single-ended CH3 MCP3008_S4 # single-ended CH4 MCP3008_S5 # single-ended CH5 MCP3008_S6 # single-ended CH6 MCP3008_S7 # single-ended CH7 MCP3008_DIFF_0_1 # differential +CH0 -CH1 MCP3008_DIFF_1_0 # differential -CH0 +CH1 MCP3008_DIFF_2_3 # differential +CH2 -CH3 MCP3008_DIFF_3_2 # differential -CH2 +CH3 MCP3008_DIFF_4_5 # differential +CH4 -CH5 MCP3008_DIFF_5_4 # differential -CH4 +CH5 MCP3008_DIFF_6_7 # differential +CH6 -CH7 MCP3008_DIFF_7_6 # differential -CH6 +CH7 You can import these constants into your namespace with use HiPi::Interface::MCP3008 qw( :mcp );