Difference between revisions of "I2C DAC"

From BitWizard WIKI
Jump to: navigation, search
(general info)
(using the board)
Line 20: Line 20:
 
  -y    don't ask confirmation
 
  -y    don't ask confirmation
 
  1    number of the I2C bus (0 on older raspberry pi's)
 
  1    number of the I2C bus (0 on older raspberry pi's)
  0x60  address of the DAC, use 0x61 for the other DAC.  
+
  0x60  address of the DAC, use 0x61 (or 0x62 and 0x63) for the other DAC.  
 
  0x40  configuration: normal.  
 
  0x40  configuration: normal.  
 
  0xff  high 8 bits of the value
 
  0xff  high 8 bits of the value
 
  0xf0  lower four bits of the value (in the high nibble)
 
  0xf0  lower four bits of the value (in the high nibble)

Revision as of 18:08, 21 March 2014

general info

Based on the MCP4726 chip from Microchip.
http://ww1.microchip.com/downloads/en/DeviceDoc/22272C.pdf

I2C address:
1100 000 and 1100 001 OR
1100 010 and 1100 011
You can order both versions. The addresses of your board can be found on the bottom side.

physical dimensions

  • Board outline: 25x25mm
  • Mounting hole diameter: 3mm
  • Mounting hole pitch: 19x19mm (3mm from board edge)

using the board

Set a voltage:

sudo i2cset -y 1 0x60 0x40 0xff 0xf0 i
                             ^^   ^     < Voltage bits

explanation of the arguments:

-y    don't ask confirmation
1     number of the I2C bus (0 on older raspberry pi's)
0x60  address of the DAC, use 0x61 (or 0x62 and 0x63) for the other DAC. 
0x40  configuration: normal. 
0xff  high 8 bits of the value
0xf0  lower four bits of the value (in the high nibble)