EM500 MiniMo® Programmable IoT Module


The EM500 is an ultra-compact Tibbo BASIC/C-programmable IoT Module with Ethernet and optional Wi-Fi* connectivity. The EM500 has one UART.

The first member of our MiniMo® family, the EM500 is designed to be used in tandem with a standard RJ45 magnetics jack. The combined footprint of the EM500 and a typical jack is only 28.5 x 18.5mm (1.12 x 0.73").

Compact dimensions, space-saving "vertical slice" form factor, low power consumption, and economical pricing make the module an excellent fit for miniature, cost-sensitive "connected" devices.

Module testing and evaluation can be performed with our EM500EV development system.

* Requires the WA2000 Wi-Fi add-on to be connected externally.

Here is How You Can Use the EM500

As a Serial-over-IP (SoI)

Serial-over-IP conversion is a large part of what we do, and there is an entire section of our website dedicated to serial converters (a.k.a. "serial device servers"). We offer a free open-source serial-over-IP (SoI) app that turns the EM500 into a full-featured serial-to-IP converter.

Build Your Own
IoT Solution

The EM500 is programmable in Tibbo BASIC and Tibbo C. Develop your very own IoT solution from scratch or take inspiration from our open-source applications and code samples published in the Code and Apps section.

Key Features

10/100 Base-T Ethernet port (no RJ45/magnetics)

Optional Wi-Fi connectivity
(with the WA2000 add-on)

1 UART, supports serial, Wiegand, and clock/data streams
8 general-purpose I/O lines (5V-tolerant)
512K flash for TiOS and application, support for external 1MB flash disk
208-byte EEPROM
Dual-function LED control (see "An Enlightening Idea" below)
Height and width of an RJ45 jack, thickness 6.5mm
3.3V power

Stands Up, Stands Out

Designed to be mounted vertically and fit behind a standard RJ45 jack, the EM500 reduces the required board space to minuscule 18.5 x 6.5mm (0.73 x 0.25"). The width and height of the EM500 are very close to those of a standard RJ45 jack.

An Enlightening Idea

How many LEDs does a typical RJ jack have? Two. How many LEDs Tibbo modules usually require? At least three – red and green status LEDs, plus one yellow Ethernet link LED.

Minimalist to the end, MiniMo makes do with just two LEDs of a typical RJ45 jack: module states are displayed using flashing patterns, while LED brightness indicates the Ethernet link state.



  • Powered by Tibbo OS (TiOS).
  • 10/100BaseT auto-MDIX Ethernet port (no magnetics).
  • Optional Wi-Fi interface (requires the WA2000 add-on module).
  • One serial port (CMOS):
    • Baudrates of up to 460,800bps;
    • None/even/odd/mark/space parity modes;
    • 7 or 8 bits/character;
    • Full-duplex mode with RTS/CTS and XON/XOFF flow control;
    • Half-duplex mode with direction control;
    • Encoding and decoding of Wiegand and clock/data streams.
  • 8 general-purpose I/O lines; 2 lines can work as interrupts.
  • 17.5KB SRAM for Tibbo BASIC/C variables and data.
  • 512KB flash memory for TiOS and application code.
  • Optional 1MB flash disk (requires an external SPI flash IC).
  • 208-byte EEPROM for data storage.
  • Three control lines for status LEDs:
    • Control lines for two external dual-function status LEDs;
    • A separate control line for the Ethernet link LED.
  • Reliable power-on/ brown-out reset circuit*.
  • Power: 260mA @ 3.3V (100Base-T mode).
  • "Vertical slice" form factor.
  • Dimensions (HxWxT): 16 x 18.5 x 6.5mm.
  • Operating temperature range: -40 ~ +70°C.
  • Firmware is upgradeable through the serial port or network.
  • Tibbo BASIC/C application can be debugged through the Ethernet LAN.
  • CE- and FCC- certified.

*Added in revision -01 of the module.

See also:


Create powerful, network-enabled applications in Tibbo BASIC and Tibbo C. Learn more...

Platform objects:

  • button — monitors the MD (setup) line.
  • fd — manages the flash memory file system and direct sector access.
  • io — handles I/O lines, ports, and interrupts.
  • net — controls the Ethernet port.
  • pat — "plays" patterns on up to five LED pairs.
  • ppp — accesses the Internet over a serial modem (4G/LTE, etc.).
  • pppoe — accesses the Internet over an ADSL modem.
  • romfile — facilitates access to resource files (fixed data).
  • ser — controls the serial port (UART, Wiegand, clock/data modes).
  • sock — socket comms (up to 16 UDP, TCP, and HTTP sessions).
  • stor — provides access to the EEPROM.
  • sys — in charge of general device functionality.
  • wln — handles the Wi-Fi interface.

Function Groups: 27 string functions, 8 date/time conversion functions, encryption/hash calculation functions (RC4, MD5, SHA-1), and more.

Variable Types: Signed and unsigned 8-bit, 16-bit, and 32-bit types; string type; user-defined arrays and structures.

Files and Documentation

TiOS Firmwaretios-em500w-3_60_06.bin — supports WA2000 add-on
SoI Firmwaresoi_application-4_30-(EM500EV).bin
Documentation EM500 Hardware Manual
EM500 Programming Platform
Serial-over-IP Solutions Manual
CE Certificateem500-em500ev-ce.pdf
FCC Certificateem500-em500ev-fcc.pdf