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50 lines
2.0 KiB
50 lines
2.0 KiB
Kernel driver adc128d818 |
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Supported chips: |
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* Texas Instruments ADC818D818 |
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Prefix: 'adc818d818' |
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Addresses scanned: I2C 0x1d, 0x1e, 0x1f, 0x2d, 0x2e, 0x2f |
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Datasheet: Publicly available at the TI website https://www.ti.com/ |
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Author: Guenter Roeck |
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Description |
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----------- |
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This driver implements support for the Texas Instruments ADC128D818. |
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It is described as 'ADC System Monitor with Temperature Sensor'. |
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The ADC128D818 implements one temperature sensor and seven voltage sensors. |
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Temperatures are measured in degrees Celsius. There is one set of limits. |
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When the HOT Temperature Limit is crossed, this will cause an alarm that will |
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be reasserted until the temperature drops below the HOT Hysteresis. |
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Measurements are guaranteed between -55 and +125 degrees. The temperature |
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measurement has a resolution of 0.5 degrees; the limits have a resolution |
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of 1 degree. |
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Voltage sensors (also known as IN sensors) report their values in volts. |
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An alarm is triggered if the voltage has crossed a programmable minimum |
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or maximum limit. Note that minimum in this case always means 'closest to |
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zero'; this is important for negative voltage measurements. All voltage |
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inputs can measure voltages between 0 and 2.55 volts, with a resolution |
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of 0.625 mV. |
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If an alarm triggers, it will remain triggered until the hardware register |
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is read at least once. This means that the cause for the alarm may |
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already have disappeared by the time the alarm is read. The driver |
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caches the alarm status for each sensor until it is at least reported |
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once, to ensure that alarms are reported to user space. |
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The ADC128D818 only updates its values approximately once per second; |
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reading it more often will do no harm, but will return 'old' values. |
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In addition to the scanned address list, the chip can also be configured for |
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addresses 0x35 to 0x37. Those addresses are not scanned. You have to instantiate |
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the driver explicitly if the chip is configured for any of those addresses in |
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your system.
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