PM_I2C Issue

Robotics & Edge Computing Jetson & Embedded Systems Jetson TX2
1

Issue description :

We have connected a temperature sensor(part number : TE connectivity HPP845E131R5) at the PM_I2C bus in Jetson TX2. We are reading the temperature value from the sensor continuously at the rate of 1 reading per second. And while doing so we find that sometimes we get “arb lost in communicate to add 0x40” error in the range of +8.0 °C to +8.76 °C.

We were not able to probe the signals exactly at that moment when the failure occurs, as the temperature Window is small. We tried to change the I2C bus from PM_I2C to I2C_GP0, in that case we were not able to see the issue in that temp range, so can you please explain this behavior as of why this error occurs in the PM_I2C in the temp range, also please find the logs below for the PM_I2C test case.

Doubts:

There are multiple devices in the PM_I2C bus in the Jetson TX2 SOM, can this issue be due to multiple devices connected in the same bus
Can we use the PM_I2C bus in that temperature range or is there any limitation in doing so?

Note:

We checked PM_I2C with both 100KHZ and 400KHZ clock rates.

Temperature value is 11.02*C 
	Temperature value is 10.99*C 
	Temperature value is 10.97*C 
	Temperature value is 10.93*C 
	Temperature value is 10.93*C 
	Temperature value is 10.90*C 
	Temperature value is 10.85*C 
	Temperature value is 10.85*C 
	Temperature value is 10.81*C 
	Temperature value is 10.80*C 
	Temperature value is 10.77*C 
	Temperature value is 10.77*C 
	Temperature value is 10.72*C 
	Temperature value is 10.71*C 
	Temperature value is 10.70*C 
	Temperature value is 10.68*C 
	Temperature value is 10.66*C 
	Temperature value is 10.63*C 
	Temperature value is 10.62*C 
	Temperature value is 10.60*C 
	Temperature value is 10.57*C 
	Temperature value is 10.53*C 
	Temperature value is 10.51*C 
	Temperature value is 10.49*C 
	Temperature value is 10.46*C 
	Temperature value is 10.44*C 
	Temperature value is 10.41*C 
	Temperature value is 10.39*C 
	Temperature value is 10.34*C 
	Temperature value is 10.34*C 
	Temperature value is 10.30*C 
	Temperature value is 10.28*C 
	Temperature value is 10.28*C 
	Temperature value is 10.24*C 
	Temperature value is 10.20*C 
	Temperature value is 10.19*C 
	Temperature value is 10.14*C 
	Temperature value is 10.09*C 
	Temperature value is 10.09*C 
	Temperature value is 10.07*C 
	Temperature value is 10.04*C 
	Temperature value is 10.04*C 
	Temperature value is 10.00*C 
	Temperature value is 9.98*C 
	Temperature value is 9.95*C 
	Temperature value is 9.92*C 
	Temperature value is 9.88*C 
	Temperature value is 9.86*C 
	Temperature value is 9.84*C 
	Temperature value is 9.80*C 
	Temperature value is 9.77*C 
	Temperature value is 9.76*C 
	Temperature value is 9.71*C 
	Temperature value is 9.69*C 
	Temperature value is 9.67*C 
	Temperature value is 9.66*C 
	Temperature value is 9.61*C 
	Temperature value is 9.59*C 
	Temperature value is 9.54*C 
	Temperature value is 9.53*C 
	Temperature value is 9.53*C 
	Temperature value is 9.49*C 
	Temperature value is 9.49*C 
	Temperature value is 9.47*C 
	Temperature value is 9.47*C 
	Temperature value is 9.41*C 
	Temperature value is 9.41*C 
	Temperature value is 9.37*C 
	Temperature value is 9.35*C 
	Temperature value is 9.34*C 
	Temperature value is 9.32*C 
	Temperature value is 9.30*C 
	Temperature value is 9.27*C 
	Temperature value is 9.25*C 
	Temperature value is 9.21*C 
	Temperature value is 9.17*C 
	Temperature value is 9.16*C 
	Temperature value is 9.14*C 
	Temperature value is 9.15*C 
	Temperature value is 9.12*C 
	Temperature value is 9.11*C 
	Temperature value is 9.11*C 
	Temperature value is 9.08*C 
	Temperature value is 9.04*C 
	Temperature value is 9.02*C 
	Temperature value is 9.00*C 
	Temperature value is 8.98*C 
	Temperature value is 8.98*C 
	Temperature value is 8.95*C 
	Temperature value is 8.93*C 
	Temperature value is 8.87*C 
	Temperature value is 8.83*C 
	Temperature value is 8.81*C 
	Temperature value is 8.79*C 
	Temperature value is 8.77*C 
	Temperature value is 8.75*C 
	Temperature value is 8.75*C 
[ 1344.454757] tegra-i2c c250000.i2c: I2C_INT_STATUS - 0x2
[ 1344.460112] tegra-i2c c250000.i2c: i2c transfer timed out addr: 0x40
[ 1344.466961] i2c_read_reg:read reg error:reg=e3,val=0 receive ret=146
[ 1344.473376] Temperature sensor : i2c error
[ 1345.549594] tegra-i2c c250000.i2c: arb lost in communicate to add 0x40
[ 1345.556749] i2c_read_reg:write reg error:reg=e3 sent ret = 245
[ 1345.562686] Temperature sensor : i2c error
[ 1348.670442] tegra-i2c c250000.i2c: I2C_INT_STATUS - 0x2
[ 1348.675742] tegra-i2c c250000.i2c: i2c transfer timed out addr: 0x40
[ 1348.682524] i2c_read_reg:read reg error:reg=e3,val=0 receive ret=146
[ 1348.689081] Temperature sensor : i2c error
[ 1349.788610] tegra-i2c c250000.i2c: arb lost in communicate to add 0x40
[ 1349.795796] i2c_read_reg:write reg error:reg=e3 sent ret = 245
[ 1349.803533] Temperature sensor : i2c error
[ 1352.918500] tegra-i2c c250000.i2c: I2C_INT_STATUS - 0x2
[ 1352.923799] tegra-i2c c250000.i2c: i2c transfer timed out addr: 0x40
[ 1352.930567] i2c_read_reg:read reg error:reg=e3,val=0 receive ret=146
[ 1352.937016] Temperature sensor : i2c error
[ 1353.988475] tegra-i2c c250000.i2c: arb lost in communicate to add 0x40
[ 1353.995496] i2c_read_reg:write reg error:reg=e3 sent ret = 245
[ 1354.001467] Temperature sensor : i2c error
[ 1357.123371] tegra-i2c c250000.i2c: I2C_INT_STATUS - 0x2
[ 1357.128978] tegra-i2c c250000.i2c: i2c transfer timed out addr: 0x40
[ 1357.135867] i2c_read_reg:read reg error:reg=e3,val=0 receive ret=146
[ 1357.142383] Temperature sensor : i2c error
[ 1358.200399] tegra-i2c c250000.i2c: arb lost in communicate to add 0x40
[ 1358.207492] i2c_read_reg:write reg error:reg=e3 sent ret = 245
[ 1358.213488] Temperature sensor : i2c error
[ 1361.358972] tegra-i2c c250000.i2c: I2C_INT_STATUS - 0x2
[ 1361.364326] tegra-i2c c250000.i2c: i2c transfer timed out addr: 0x40
[ 1361.373908] i2c_read_reg:read reg error:reg=e3,val=0 receive ret=146
[ 1361.380508] Temperature sensor : i2c error
[ 1362.474286] tegra-i2c c250000.i2c: arb lost in communicate to add 0x40
[ 1362.481301] i2c_read_reg:write reg error:reg=e3 sent ret = 245
[ 1362.487281] Temperature sensor : i2c error
[ 1365.604013] tegra-i2c c250000.i2c: I2C_INT_STATUS - 0x2
[ 1365.609310] tegra-i2c c250000.i2c: i2c transfer timed out addr: 0x40
[ 1365.615949] i2c_read_reg:read reg error:reg=e3,val=0 receive ret=146
[ 1365.622371] Temperature sensor : i2c error
[ 1366.672183] tegra-i2c c250000.i2c: arb lost in communicate to add 0x40
[ 1366.679235] i2c_read_reg:write reg error:reg=e3 sent ret = 245
[ 1366.685282] Temperature sensor : i2c error
[ 1369.814492] tegra-i2c c250000.i2c: I2C_INT_STATUS - 0x2
[ 1369.819836] tegra-i2c c250000.i2c: i2c transfer timed out addr: 0x40
[ 1369.829317] i2c_read_reg:read reg error:reg=e3,val=0 receive ret=146
[ 1369.836054] Temperature sensor : i2c error
[ 1370.930558] tegra-i2c c250000.i2c: arb lost in communicate to add 0x40
[ 1370.937624] i2c_read_reg:write reg error:reg=e3 sent ret = 245
[ 1370.943853] Temperature sensor : i2c error
[ 1374.072127] tegra-i2c c250000.i2c: I2C_INT_STATUS - 0x2
[ 1374.077431] tegra-i2c c250000.i2c: i2c transfer timed out addr: 0x40
[ 1374.084244] i2c_read_reg:read reg error:reg=e3,val=0 receive ret=146
[ 1374.090696] Temperature sensor : i2c error
[ 1375.146358] tegra-i2c c250000.i2c: arb lost in communicate to add 0x40
[ 1375.153368] i2c_read_reg:write reg error:reg=e3 sent ret = 245
[ 1375.159382] Temperature sensor : i2c error
	Temperature value is 8.01*C 
	Temperature value is 7.99*C 
	Temperature value is 7.96*C 
	Temperature value is 7.93*C 
	Temperature value is 7.92*C 
	Temperature value is 7.90*C 
	Temperature value is 7.89*C 
	Temperature value is 7.87*C 
	Temperature value is 7.85*C 
	Temperature value is 7.84*C 
	Temperature value is 7.83*C 
	Temperature value is 7.81*C 
	Temperature value is 7.78*C 
	Temperature value is 7.76*C 
	Temperature value is 7.76*C 
	Temperature value is 7.74*C 
	Temperature value is 7.71*C 
	Temperature value is 7.65*C 
	Temperature value is 7.64*C 
	Temperature value is 7.63*C 
	Temperature value is 7.60*C 
	Temperature value is 7.59*C 
	Temperature value is 7.56*C 
	Temperature value is 7.57*C 
	Temperature value is 7.56*C 
	Temperature value is 7.54*C 
	Temperature value is 7.50*C 
	Temperature value is 7.48*C 
	Temperature value is 7.45*C 
	Temperature value is 7.42*C 
	Temperature value is 7.40*C 
	Temperature value is 7.40*C 
	Temperature value is 7.38*C 
	Temperature value is 7.37*C 
	Temperature value is 7.35*C 
	Temperature value is 7.33*C 
	Temperature value is 7.29*C 
	Temperature value is 7.27*C

Temperature value is 5.01*C 
	Temperature value is 5.03*C 
	Temperature value is 5.05*C 
	Temperature value is 5.07*C 
	Temperature value is 5.09*C 
	Temperature value is 5.11*C 
	Temperature value is 5.13*C 
	Temperature value is 5.16*C 
	Temperature value is 5.18*C 
	Temperature value is 5.21*C 
	Temperature value is 5.22*C 
	Temperature value is 5.24*C 
	Temperature value is 5.28*C 
	Temperature value is 5.30*C 
	Temperature value is 5.32*C 
	Temperature value is 5.35*C 
	Temperature value is 5.36*C 
	Temperature value is 5.38*C 
	Temperature value is 5.42*C 
	Temperature value is 5.43*C 
	Temperature value is 5.47*C 
	Temperature value is 5.48*C 
	Temperature value is 5.51*C 
	Temperature value is 5.51*C 
	Temperature value is 5.54*C 
	Temperature value is 5.57*C 
	Temperature value is 5.57*C 
	Temperature value is 5.61*C 
	Temperature value is 5.62*C 
	Temperature value is 5.65*C 
	Temperature value is 5.67*C 
	Temperature value is 5.68*C 
	Temperature value is 5.70*C 
	Temperature value is 5.72*C 
	Temperature value is 5.75*C 
	Temperature value is 5.77*C 
	Temperature value is 5.79*C 
	Temperature value is 5.81*C 
	Temperature value is 5.82*C 
	Temperature value is 5.85*C 
	Temperature value is 5.89*C 
	Temperature value is 5.90*C 
	Temperature value is 5.92*C 
	Temperature value is 5.94*C 
	Temperature value is 5.96*C 
	Temperature value is 5.98*C 
	Temperature value is 5.99*C 
	Temperature value is 6.02*C 
	Temperature value is 6.05*C 
	Temperature value is 6.06*C 
	Temperature value is 6.09*C 
	Temperature value is 6.11*C 
	Temperature value is 6.14*C 
	Temperature value is 6.14*C 
	Temperature value is 6.16*C 
	Temperature value is 6.19*C 
	Temperature value is 6.21*C 
	Temperature value is 6.23*C 
	Temperature value is 6.26*C 
	Temperature value is 6.27*C 
	Temperature value is 6.28*C 
	Temperature value is 6.31*C 
	Temperature value is 6.33*C 
	Temperature value is 6.36*C 
	Temperature value is 6.38*C 
	Temperature value is 6.41*C 
	Temperature value is 6.41*C 
	Temperature value is 6.42*C 
	Temperature value is 6.45*C 
	Temperature value is 6.45*C 
	Temperature value is 6.48*C 
	Temperature value is 6.50*C 
	Temperature value is 6.51*C 
	Temperature value is 6.54*C 
	Temperature value is 6.56*C 
	Temperature value is 6.58*C 
	Temperature value is 6.60*C 
	Temperature value is 6.61*C 
	Temperature value is 6.64*C 
	Temperature value is 6.67*C 
	Temperature value is 6.69*C 
	Temperature value is 6.69*C 
	Temperature value is 6.72*C 
	Temperature value is 6.73*C 
	Temperature value is 6.76*C 
	Temperature value is 6.79*C 
	Temperature value is 6.81*C 
	Temperature value is 6.83*C 
	Temperature value is 6.85*C 
	Temperature value is 6.86*C 
	Temperature value is 6.89*C 
	Temperature value is 6.90*C 
	Temperature value is 6.93*C 
	Temperature value is 6.95*C 
	Temperature value is 6.97*C 
	Temperature value is 6.98*C 
	Temperature value is 7.00*C 
	Temperature value is 7.01*C 
	Temperature value is 7.03*C 
	Temperature value is 7.03*C 
	Temperature value is 7.07*C 
	Temperature value is 7.10*C 
	Temperature value is 7.12*C 
	Temperature value is 7.14*C 
	Temperature value is 7.15*C 
	Temperature value is 7.17*C 
	Temperature value is 7.19*C 
	Temperature value is 7.19*C 
	Temperature value is 7.22*C 
	Temperature value is 7.25*C 
	Temperature value is 7.26*C 
	Temperature value is 7.28*C 
	Temperature value is 7.29*C 
	Temperature value is 7.31*C 
	Temperature value is 7.32*C 
	Temperature value is 7.35*C 
	Temperature value is 7.37*C 
	Temperature value is 7.38*C 
	Temperature value is 7.40*C 
	Temperature value is 7.42*C 
	Temperature value is 7.43*C 
	Temperature value is 7.45*C 
	Temperature value is 7.48*C 
	Temperature value is 7.48*C 
	Temperature value is 7.52*C 
	Temperature value is 7.53*C 
	Temperature value is 7.55*C 
	Temperature value is 7.57*C 
	Temperature value is 7.59*C 
	Temperature value is 7.59*C 
	Temperature value is 7.62*C 
	Temperature value is 7.64*C 
	Temperature value is 7.67*C 
	Temperature value is 7.68*C 
	Temperature value is 7.70*C 
	Temperature value is 7.71*C 
	Temperature value is 7.73*C 
	Temperature value is 7.75*C 
	Temperature value is 7.75*C 
	Temperature value is 7.76*C 
	Temperature value is 7.79*C 
	Temperature value is 7.79*C 
	Temperature value is 7.83*C 
	Temperature value is 7.84*C 
	Temperature value is 7.87*C 
	Temperature value is 7.88*C 
	Temperature value is 7.90*C 
	Temperature value is 7.91*C 
	Temperature value is 7.93*C 
	Temperature value is 7.94*C 
	Temperature value is 7.97*C 
	Temperature value is 7.98*C 
	Temperature value is 8.01*C 
	Temperature value is 8.01*C 
	Temperature value is 8.02*C 
	Temperature value is 8.05*C 
	Temperature value is 8.05*C 
[ 3042.246526] tegra-i2c c250000.i2c: I2C_INT_STATUS - 0x2
[ 3042.251895] tegra-i2c c250000.i2c: i2c transfer timed out addr: 0x40
[ 3042.258739] i2c_read_reg:read reg error:reg=e3,val=0 receive ret=146
[ 3042.265301] Temperature sensor : i2c error
[ 3043.337897] tegra-i2c c250000.i2c: arb lost in communicate to add 0x40
[ 3043.345035] i2c_read_reg:write reg error:reg=e3 sent ret = 245
[ 3043.350950] Temperature sensor : i2c error
[ 3046.478015] tegra-i2c c250000.i2c: I2C_INT_STATUS - 0x2
[ 3046.483487] tegra-i2c c250000.i2c: i2c transfer timed out addr: 0x40
[ 3046.492010] i2c_read_reg:read reg error:reg=e3,val=0 receive ret=146
[ 3046.498647] Temperature sensor : i2c error
[ 3047.554482] tegra-i2c c250000.i2c: arb lost in communicate to add 0x40
[ 3047.561494] i2c_read_reg:write reg error:reg=e3 sent ret = 245
[ 3047.567510] Temperature sensor : i2c error
[ 3050.674300] tegra-i2c c250000.i2c: I2C_INT_STATUS - 0x2
[ 3050.679602] tegra-i2c c250000.i2c: i2c transfer timed out addr: 0x40
[ 3050.686372] i2c_read_reg:read reg error:reg=e3,val=0 receive ret=146
[ 3050.692842] Temperature sensor : i2c error
[ 3051.772455] tegra-i2c c250000.i2c: arb lost in communicate to add 0x40
[ 3051.779715] i2c_read_reg:write reg error:reg=e3 sent ret = 245
[ 3051.787680] Temperature sensor : i2c error
[ 3054.915288] tegra-i2c c250000.i2c: I2C_INT_STATUS - 0x2
[ 3054.920694] tegra-i2c c250000.i2c: i2c transfer timed out addr: 0x40
[ 3054.927540] i2c_read_reg:read reg error:reg=e3,val=0 receive ret=146
[ 3054.934035] Temperature sensor : i2c error
[ 3056.026899] tegra-i2c c250000.i2c: arb lost in communicate to add 0x40
[ 3056.037026] i2c_read_reg:write reg error:reg=e3 sent ret = 245
[ 3056.043420] Temperature sensor : i2c error
[ 3059.171739] tegra-i2c c250000.i2c: I2C_INT_STATUS - 0x2
[ 3059.177128] tegra-i2c c250000.i2c: i2c transfer timed out addr: 0x40
[ 3059.183931] i2c_read_reg:read reg error:reg=e3,val=0 receive ret=146
[ 3059.190347] Temperature sensor : i2c error
[ 3060.269166] tegra-i2c c250000.i2c: arb lost in communicate to add 0x40
[ 3060.276253] i2c_read_reg:write reg error:reg=e3 sent ret = 245
[ 3060.282272] Temperature sensor : i2c error
[ 3063.382899] tegra-i2c c250000.i2c: I2C_INT_STATUS - 0x2
[ 3063.388272] tegra-i2c c250000.i2c: i2c transfer timed out addr: 0x40
[ 3063.395167] i2c_read_reg:read reg error:reg=e3,val=0 receive ret=146
[ 3063.401586] Temperature sensor : i2c error
[ 3064.467083] tegra-i2c c250000.i2c: arb lost in communicate to add 0x40
[ 3064.474269] i2c_read_reg:write reg error:reg=e3 sent ret = 245
[ 3064.480304] Temperature sensor : i2c error
[ 3067.586455] tegra-i2c c250000.i2c: I2C_INT_STATUS - 0x2
[ 3067.591761] tegra-i2c c250000.i2c: i2c transfer timed out addr: 0x40
[ 3067.598532] i2c_read_reg:read reg error:reg=e3,val=0 receive ret=146
[ 3067.605006] Temperature sensor : i2c error
[ 3068.686284] tegra-i2c c250000.i2c: arb lost in communicate to add 0x40
[ 3068.693390] i2c_read_reg:write reg error:reg=e3 sent ret = 245
[ 3068.699420] Temperature sensor : i2c error
[ 3071.828755] tegra-i2c c250000.i2c: I2C_INT_STATUS - 0x2
[ 3071.834051] tegra-i2c c250000.i2c: i2c transfer timed out addr: 0x40
[ 3071.840741] i2c_read_reg:read reg error:reg=e3,val=0 receive ret=146
[ 3071.847197] Temperature sensor : i2c error
[ 3072.906557] tegra-i2c c250000.i2c: arb lost in communicate to add 0x40
[ 3072.916800] i2c_read_reg:write reg error:reg=e3 sent ret = 245
[ 3072.922808] Temperature sensor : i2c error
[ 3076.038792] tegra-i2c c250000.i2c: I2C_INT_STATUS - 0x2
[ 3076.044116] tegra-i2c c250000.i2c: i2c transfer timed out addr: 0x40
[ 3076.050905] i2c_read_reg:read reg error:reg=e3,val=0 receive ret=146
[ 3076.057307] Temperature sensor : i2c error
[ 3077.118060] tegra-i2c c250000.i2c: arb lost in communicate to add 0x40
[ 3077.125181] i2c_read_reg:write reg error:reg=e3 sent ret = 245
[ 3077.131440] Temperature sensor : i2c error
	Temperature value is 8.75*C 
	Temperature value is 8.78*C 
	Temperature value is 8.80*C 
	Temperature value is 8.81*C 
	Temperature value is 8.82*C 
	Temperature value is 8.86*C 
	Temperature value is 8.87*C 
	Temperature value is 8.88*C 
	Temperature value is 8.91*C 
	Temperature value is 8.93*C 
	Temperature value is 8.94*C 
	Temperature value is 8.97*C 
	Temperature value is 8.98*C 
	Temperature value is 9.01*C 
	Temperature value is 9.03*C 
	Temperature value is 9.04*C 
	Temperature value is 9.06*C 
	Temperature value is 9.08*C 
	Temperature value is 9.10*C 
	Temperature value is 9.14*C 
	Temperature value is 9.15*C 
	Temperature value is 9.18*C 
	Temperature value is 9.19*C 
	Temperature value is 9.22*C 
	Temperature value is 9.24*C 
	Temperature value is 9.27*C 
	Temperature value is 9.29*C 
	Temperature value is 9.31*C 
	Temperature value is 9.33*C 
	Temperature value is 9.36*C 
	Temperature value is 9.37*C 
	Temperature value is 9.39*C 
	Temperature value is 9.41*C 
	Temperature value is 9.42*C 
	Temperature value is 9.46*C 
	Temperature value is 9.48*C 
	Temperature value is 9.49*C 
	Temperature value is 9.51*C 
	Temperature value is 9.53*C 
	Temperature value is 9.55*C 
	Temperature value is 9.57*C 
	Temperature value is 9.59*C 
	Temperature value is 9.61*C 
	Temperature value is 9.62*C 
	Temperature value is 9.64*C 
	Temperature value is 9.66*C 
	Temperature value is 9.69*C 
	Temperature value is 9.69*C 
	Temperature value is 9.72*C 
	Temperature value is 9.75*C 
	Temperature value is 9.77*C 
	Temperature value is 9.79*C 
	Temperature value is 9.80*C 
	Temperature value is 9.82*C 
	Temperature value is 9.84*C 
	Temperature value is 9.86*C 
	Temperature value is 9.89*C 
	Temperature value is 9.91*C 
	Temperature value is 9.93*C 
	Temperature value is 9.95*C 
	Temperature value is 9.97*C 
	Temperature value is 10.00*C 
	Temperature value is 10.01*C 
	Temperature value is 10.06*C 
	Temperature value is 10.06*C 
	Temperature value is 10.08*C 
	Temperature value is 10.11*C 
	Temperature value is 10.13*C 
	Temperature value is 10.16*C 
	Temperature value is 10.20*C 
	Temperature value is 10.22*C 
	Temperature value is 10.23*C 
	Temperature value is 10.25*C 
	Temperature value is 10.26*C 
	Temperature value is 10.29*C 
	Temperature value is 10.31*C 
	Temperature value is 10.34*C 
	Temperature value is 10.36*C 
	Temperature value is 10.38*C 
	Temperature value is 10.41*C 
	Temperature value is 10.43*C 
	Temperature value is 10.45*C 
	Temperature value is 10.48*C 
	Temperature value is 10.50*C 
	Temperature value is 10.51*C 
	Temperature value is 10.54*C 
	Temperature value is 10.55*C 
	Temperature value is 10.57*C 
	Temperature value is 10.60*C 
	Temperature value is 10.62*C 
	Temperature value is 10.65*C 
	Temperature value is 10.66*C 
	Temperature value is 10.68*C 
	Temperature value is 10.70*C 
	Temperature value is 10.72*C 
	Temperature value is 10.75*C 
	Temperature value is 10.77*C 
	Temperature value is 10.79*C 
	Temperature value is 10.82*C 
	Temperature value is 10.84*C 
	Temperature value is 10.86*C 
	Temperature value is 10.87*C 
	Temperature value is 10.90*C 
	Temperature value is 10.94*C 
	Temperature value is 10.95*C 
	Temperature value is 10.97*C 
	Temperature value is 10.99*C 
	Temperature value is 11.02*C 
	Temperature value is 11.03*C 
	Temperature value is 11.05*C 
	Temperature value is 11.09*C 
	Temperature value is 11.10*C 
	Temperature value is 11.12*C 
	Temperature value is 11.14*C 
	Temperature value is 11.16*C 
	Temperature value is 11.18*C 
	Temperature value is 11.20*C 
	Temperature value is 11.23*C 
	Temperature value is 11.25*C 
	Temperature value is 11.28*C 
	Temperature value is 11.29*C 
	Temperature value is 11.32*C 
	Temperature value is 11.34*C 
	Temperature value is 11.37*C 
	Temperature value is 11.39*C 
	Temperature value is 11.41*C 
	Temperature value is 11.43*C 
	Temperature value is 11.45*C 
	Temperature value is 11.46*C 
	Temperature value is 11.48*C 
	Temperature value is 11.53*C 
	Temperature value is 11.55*C 
	Temperature value is 11.57*C 
	Temperature value is 11.60*C 
	Temperature value is 11.60*C 
	Temperature value is 11.62*C 
	Temperature value is 11.66*C 
	Temperature value is 11.67*C 
	Temperature value is 11.70*C 
	Temperature value is 11.73*C 
	Temperature value is 11.75*C 
	Temperature value is 11.76*C 
	Temperature value is 11.78*C 
	Temperature value is 11.82*C 
	Temperature value is 11.83*C 
	Temperature value is 11.86*C 
	Temperature value is 11.88*C 
	Temperature value is 11.90*C 
	Temperature value is 11.91*C 
	Temperature value is 11.93*C 
	Temperature value is 11.96*C 
	Temperature value is 11.98*C 
	Temperature value is 12.01*C

PM_I2C test result.txt (205 KB)

2

It is not suggested to use PM I2C for this kind of frequently reading device, as there are several thermal senors on it and eeprom in module on it. If want to deeply investigate it, the waveform checking is necessary, that will show what happen on the lines when issue come out.

3

We have tested the sensor and the probed the I2C signal during the failure case and this is the result of the testing, we probed the last 3 bytes of temp data that the sensor has sent and after that the SDA line is pulled low.

The SDA line is pulled low for 4 seconds due to which no I2C communication can be made to the humidity sensor and we get a “arb lost in communicate to add 0x40” error.

The below image shows the pass condition of the sensor temperature reading cycle during 40 and 7 degree Celsius

Pass case during 40 degree Celsius:
Refer: 40DC.png

Pass case during 7 degree celcius:
Refer: 7DC.png

In both the abpve cases the SDA line and SCL line return to high state after the last ACK from the slave.

The failure occurs only during the temp range of 8-8.75 degree celcius:
Refer: 8_8.75.png

The SDA line is pulled low after the last ACK from the humidity sensor and this line stays low for 4 seconds and after 4 seconds the master toggels the SCL line and the SDA line is released from the low state and return to high
Refer: master_toggle.png

After this the SDA and SCL are both in the high state and the communication starts again and the SDA line is again pulled low after the last ACK signal whenever it is in the 8-8.75 degree celcius temp range.
7DC.png
8_8.75.png
40DC.png
master_toggle.png

4

Hi, still, it is not suggested to use PM I2C for this kind of frequently reading device

5

we even polled the temperature sensor at the rate of 1 reading per minute.
If we hold the temperature in the temperature range 8-8.75 degree celcius then we are getting continuous failure errors.

This issue seems to occur in the temperature range 8-8.75 degree celcius and not due to frequent polling.

6

Can you try using other I2C to do this test? If this issue occur in the temperature range, it should be nothing to do with I2C.

7

Hi, we have tried using I2C_GP0 bus as we already mentioned in the first post. This issue doesn’t occur in that temperature range.

8

Hi, it is better to capture the waveform to check the signal quality and if it is possible the waveform of reading temperature (8-8.75C) has any conflict to other devices on bus.