commissioning of revision 2.0

[JochiSt]

This issue is about the commissioning of the first board of rev 2.0.

The firmware is prepared and should hopefully work out of the box.

[JochiSt]

Population changes

• C19 & C20 22p instead of 27p
• SGM8522XS instead of LT1492 (LT1490A) (but only for PWM filtering, for the others, the maximal supply voltage is too low)
• TMP101 instead of TMP100

[JochiSt]

Startup working:

I2C Bus Scanning

I2C bus #1
Scanning I2C bus:
.......................................................................0x48.............................................0x76.........

Two devices as expected found:

• 0x48 = TMP101
• 0x76 = BME688

[JochiSt]

When the EEPROM (24LC01) is inserted it is also recognised on I2C Bus 1

0x48.......0x50 0x51 0x52 0x53 0x54 0x55 0x56 0x57..............................0x76.........

This matches the address pattern used in the 24LC01. datasheet

[JochiSt]

Gain of I and U

Channel 0

Channel 1

Should be dominated by the low gain for low DAC settings and by the saturation for the high DAC settings.

[JochiSt]

Gain vs DAC settings. A bit better plot than before.

The resistance calculated from the data above.

Because the current / voltage resolution could be better, I'll decrease R50, R51, R52, R53 to increase the gain.

[JochiSt]

reading and writing the configuration works.

example setting TMP100 interval to 64

Getting the configuration from OFM
Board ID: 1
Intervals:
    CAN ADC    4
    Print UART 8
        I2C TMP100 1
        I2C BME680 255

PIDflags 0x0
PID 0
    T: 40.000000
    P: 0.000000
    I: 0.000000
    D: 0.000000

PID 1
    T: 40.000000
    P: 0.000000
    I: 0.000000
    D: 0.000000

Smoothing:
    SMOO     15
    SMOO_MAX 16

Here is the change done, the interval is set to 64. (Note: sometimes, this does not work on the first try. But this might be related to the CAN bus...)

Board ID: 1
Intervals:
    CAN ADC    4
    Print UART 8
        I2C TMP100 64
        I2C BME680 255

PIDflags 0x0
PID 0
    T: 40.000000
    P: 0.000000
    I: 0.000000
    D: 0.000000

PID 1
    T: 40.000000
    P: 0.000000
    I: 0.000000
    D: 0.000000

Smoothing:
    SMOO     15
    SMOO_MAX 16

[JochiSt]

After triggering the writing of the configuration into the EEPROM, the configuration is changed on reboot / power cycling.

[JochiSt]

internal PID working

Note: not tuned to any performance, but with a simple P of 0.9 this algorithm starts regulating the temperature.

The PID was enabled just for channel 1 (the lower plot in the image)

In between I have blown some air to the sensor, that's why the DAC settings goes up.

[JochiSt]

With this all major components of the board are working. (Except BME680, which I have not yet implemented).