Programmable Boards and Modules
This information pertains to Tibbo's programmable IoT boards (EM1001 and EM2001) and embedded modules (EM500, EM510, EM1000, EM1202, EM1206, EM2000, and WM2000).
Updating these devices via a serial port can be tricky, as they don't have proper RS232 ports, but only "TTL/CMOS-level" UART(s). There is an easy solution for Tibbo modules that have not been embedded in a host device: Such modules can be upgraded using their evaluation (EV) boards. We offer EV boards for every model of our programmable modules. Unfortunately, there are no EV boards for our programmable boards.
Below is a step-by-step guide to wiring a board or module for a serial upgrade.
Only two lines are required: TX and RX. Since Tibbo boards and modules have TTL/CMOS-level UARTs, an RS232 transceiver (MAX232 or similar) is necessary to connect the device's TX and RX lines to your PC's COM port (or a USB-to-serial adapter). To begin the update, boot into the Monitor/Loader by powering on the device while pulling the MD line LOW. For example, you can connect a push button between the MD line and the ground. You will also need a power source that provides regulated 3.3V power.
The EM1001, EM2001, EM2000, and WM2000 have built-in green, red, and yellow status LEDs. For other devices, you can connect the LEDs externally.
The above diagram illustrates how to wire the EM1000 module for a serial upgrade, but a similar arrangement can be used for other boards and modules.