Current Events

The ee203 RTCM provides a self-calibration facility to maintain its performance over temperature and voltage variations. The simplified block diagram below shows the on-board current sink that can sink a calibrated amount of current from the DUT terminal. The current sink is accurate to 2%, and has selectable values of 100 mA, 1 mA, 10 uA, and off. The [C]alibration command uses the current sink to generate two data points and then interpolates (and extrapolates) from those points in normal operation. The ee203 has two sensing ranges, one above and one below 1 mA. This two point calibration operation is...

The ee203 has an integral bootloader to allow field updates of the firmware. Updates are performed by dragging a firmware image onto a USB flash drive. For performance reasons the flash drive does not appear when the bootloader is not active. The ee203 has two operating modes: bootloader and application. Bootloader mode allows the firmware to be updated, and application mode is the normal RTCM functionality. On power-up, when the USB cable is connected to the PC, the voltage at the SUPPLY terminal is sampled. If the voltage is less than 1.5V, the bootloader is launched, otherwise the application is...