Power, Reset, and Control Lines

Power

The WM2000 should be powered from a stabilized DC power supply with a nominal output voltage of 3.3V (±5% tolerance). This power should be applied to the VCC pin (#24).

The current consumption of the WM2000 is approximately 150mA with Wi-Fi enabled and scanning. The burst current might (infrequently) reach 500mA. Therefore, providing an adequate power supply is very important — a poorly built circuit could affect the WM2000's operation.

For correct device operation, the VCCB line should always be connected.

Reset

The WM2000 has a reliable power-on reset circuit but no brownout detection circuit. Therefore, an external reset circuit is not required but is recommended, especially in applications where proper brownout behavior is desired.

Pulling this line LOW will trigger a reset of the device.

To take advantage of the internal power-on reset, leave the RST pin unconnected. You can also wire in an external reset button.

MD Line

The function of the MD line is described in Setup (MD) Button (Line).

On the WM2000, the line can be used to:

• Enter the Monitor/Loader (M/L)
• Force-boot into APP0 even if the module is configured to select APP1
• Access the BLE console
• Restore Device Configuration Block (DCB) parameters to their factory defaults

HM Line

The use of the HM (hardware monitor) line is reserved as the last-resort method to recover a "bricked" module. This line is needed for re-flashing the device's bootloader.

This line is active HIGH and is pulled LOW internally, so no additional components are required for normal operation. We recommend that you leave this line unconnected.

To re-flash the bootloader, pull this line HIGH (by connecting it to VCC) before the module is turned on or released from reset.

For more information on rescuing your WM2000, contact Tibbo Support.