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interfaces:slicepi [2015/01/12 07:11] – [Power] darroninterfaces:slicepi [2024/07/10 12:30] (current) – external edit 127.0.0.1
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 <wrap right> <wrap right>
 {{:interfaces:rpipio.jpg?200}} {{:interfaces:rpipio.jpg?200}}
 +\\ \\
 +{{:interfaces:slipi.jpg?200}}
 </wrap> </wrap>
  
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 === RPi I2C === === RPi I2C ===
-Enable I2C on the RPi as root.+ 
 +== Without device tree ==
 <code> <code>
 sed -i 's/^blacklist/#blacklist/g' /etc/modprobe.d/raspi-blacklist.conf sed -i 's/^blacklist/#blacklist/g' /etc/modprobe.d/raspi-blacklist.conf
-echo 'SUBSYSTEM=="i2c-dev", MODE="0666"' >> /etc/udev/rules.d/10-local.rules+</code> 
 + 
 +== With device tree == 
 +<code> 
 +echo "device_tree_param=i2c1=on" >> /boot/config.txt 
 +</code> 
 + 
 +== With and without device tree == 
 +<code> 
 +echo 'SUBSYSTEM=="i2c-dev", MODE:="0666"' >> /etc/udev/rules.d/10-local.rules
 echo "options i2c_bcm2708 baudrate=400000" >> /etc/modprobe.d/modprobe.conf echo "options i2c_bcm2708 baudrate=400000" >> /etc/modprobe.d/modprobe.conf
 echo 'i2c-dev' >> /etc/modules echo 'i2c-dev' >> /etc/modules
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 </code> </code>
  
-For the MCP23017 a baudrate of 900000 has been tested and appears to work +For the MCP23017 a baudrate of 900000 has been tested and appears to work satisfactorily. You should experiment with this value.
-satisfactorily. You should experiment with this value.+
  
 === I/O === === I/O ===
-^RPi version ^I2C device ^Default MCP Address|+^RPi revision ^I2C device ^Default MCP Address|
 | 1 |/dev/i2c-0 |0x20| | 1 |/dev/i2c-0 |0x20|
 | 2 |/dev/i2c-1 |0x20| | 2 |/dev/i2c-1 |0x20|
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 Separate data I/O connections (only supported option) Separate data I/O connections (only supported option)
 +
 +==Wiring==
  
 <code> <code>
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    - Not used by all LVP compatible devices.     - Not used by all LVP compatible devices. 
  
 +==Config==
 +<code>
 +VPP=0     # A0
 +PGC=1     # A1
 +PGDO=2    # A2
 +PGDI=3    # A3
 +PGM=-1
 +DEVICE=MCP230XX
 +IFACE=/dev/i2c-1
 +ADDR=0x20
 +SLEEP=0
 +#VPP_RUN + PGD_IN_PULLUP
 +BITRULES=0x1010
 +</code>
 +===Resources===
 +
 +{{downloads:Slice_Pi.pdf|Assembly manual}}