MP200 units may display a clock notification if the supercapacitor has been fully discharged.

What the Notification Means

The MP200 has a real-time clock (RTC) circuit that allows it to “know” the time of day. This clock requires persistent power if it is to continue keeping time. The MP200 includes a supercapacitor that stores charge while the device is powered on, and continues to power the clock when the unit is shut down. When fully charged, the supercapacitor will keep the clock running for about a week. If the unit has been powered down for more than a week, the supercapacitor will be fully discharged, and the clock will stop.

The MP200 runs various self-check operations to ensure the device is functioning properly. When first powered on, the device checks to see if the real-time clock is functioning and also checks to confirm operation of the I2C communication bus through which the microprocessor exchanges information with the clock. If the supercapacitor has been fully discharged, both of these tests will fail. This is normal and expected behavior. Users will see this sequence:

1. The first time the MP200 device is powered up with a depleted supercapacitor, the device will report a pair of errors: E10004, RTC I2C error, and E10030, RTC not detected.
2. After the unit has been powered for five to ten minutes, these error messages will not be repeated if the device is re-started, but a new warning will appear: W10200, RTC Low Battery.
3. If the unit has been powered on for 3o minutes before the power is cycled again, there will be no new warnings or errors related to the RTC and I2C bus.

How to clear errors/warning from the OLED

1. Open a graph window.
2. Choose “MP200 > MP200 Info…”
3. Select the “Log” tab.
4. Press the “Delete” button in the OLED content box.
5. When prompted, confirm you want to delete the errors/warning from the OLED.

Note: The errors/warning will remain in the LOG file irrespective of whether they have been deleted from the OLED screen.

If the device is powered off for more than a week (less if the unit has not been powered on long enough to fully charge the supercapacitor), the above sequence will repeat. This is NOT an indication that there is anything wrong with the device.

The RTC can be synchronized to a network time (SNTP) server or to the host computer. Options for synchronizing the clock are available through the “Clock Settings” tab of the MP200 Info window. When the supercapacitor has been fully discharged, though, the clock is temporarily inaccessible. This is also normal behavior. SNTP synchronization is available when the MP200 is connected directly to an Ethernet network, while synchronizing to computer requires the device to be connected via Ethernet cable (with or without ETHUSB) to a host computer.