IoTGateway/BSP/Android/Gettingstarted/How to use I2C

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Test

Check i2c busses

  • Usage: i2cdetect [-y] [-a] [-q|-r] I2CBUS [FIRST LAST]
#i2cdetect -l
i2c-0   i2c             21a0000.i2c                             I2C adapter
i2c-1   i2c             21a4000.i2c                             I2C adapter
i2c-2   i2c             21a8000.i2c                             I2C adapter

Check devices on i2c-2 bus

#i2cdetect -y -r 2
     0  1  2  3  4  5  6  7  8  9  a  b  c  d  e  f
00:          -- -- -- -- -- -- -- -- -- -- -- -- --
10: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
20: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
30: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
40: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
50: UU UU -- -- -- -- -- -- -- -- -- -- -- -- -- --
60: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
70: -- -- -- -- -- -- UU --

Dump I2C device register content

  • Usage: i2cdump [-f] [-y] [-r first-last] I2CBUS ADDRESS [MODE [BANK [BANKREG]]]
# i2cdump -y -f 2 0x76
No size specified (using byte-data access)
     0  1  2  3  4  5  6  7  8  9  a  b  c  d  e  f    0123456789abcdef
00: 54 00 80 43 40 40 40 00 00 00 00 00 00 00 ff ff    T.?C@@@S........
10: 85 ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff    ?...............
20: 00 00 00 18 ff ff ff ff ff ff ff ff ff ff ff ff    ...?............
30: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff    ................
40: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff    ................
50: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff    ................
60: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff    ................
70: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff    ................
80: 54 00 80 43 40 40 40 53 00 00 00 00 00 00 ff ff    T.?C@@@S........
90: 85 ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff    ?...............
a0: 00 00 00 18 ff ff ff ff ff ff ff ff ff ff ff ff    ...?............
b0: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff    ................
c0: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff    ................
d0: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff    ................
e0: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff    ................
f0: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff    ................


Read a single byte

  • Usage: i2cget [-f] [-y] I2CBUS CHIP-ADDRESS [DATA-ADDRESS [MODE]]
# i2cget -f -y 2 0x76 7
0x00

Change its value and verify it

  • Usage: i2cset [-f] [-y] [-m MASK] [-r] I2CBUS CHIP-ADDRESS DATA-ADDRESS [VALUE] ... [MODE]
# i2cset -f -y 2 0x76 7 0x53
# i2cget -f -y 2 0x76 7
0x53