NEXUS EC200A-EU Modem

Basic Overview #

Meet a compact, rugged modem built for M2M and IoT projects where reliability, performance, and ease-of-integration matter — now available with built-in Python support for fast prototyping and flexible device logic.

Features #

Cellular performance: LTE Cat 4 — up to 150 Mbps downlink / 50 Mbps uplink (3GPP Rel.9). Backward compatible with UMTS/HSPA+ and GSM/GPRS/EDGE for broad global coverage and reliable fallback in remote areas.
Global variants: Available in CN / EU / AU band variants to match regional frequency plans.
Hardware compatibility: Compact, unified form factor compatible with Quectel EC25/EC21/EC20-CE/EG25-G/EC200U and UC200T families for easy migration and design reuse.
MIMO support: Improves throughput and link reliability for demanding data applications.
Durable design: Laser-engraved housing — better heat dissipation, a durable label, and a premium metallic finish suited to industrial use.
Over‑the‑air updates: Supports Delta Firmware OTA (DFOTA) for efficient field upgrades.

Function Description #

NEXUS EC200A-EU Modem pin diagram — **Pinout of the NEXUS EC200A-EU Modem**

NO.	Name	Silkscreen	Comment
1	USER_KEY	S1	Scheduling capability
2	Ethernet	J1	Ethernet connector
3	DRX_ANHT	SMA2_DIV	Sma connector
4	SIM Card	SimCard	Simcard case
5	USB_type_C/POWER+5	USB1	Power and data
6	MAIN_ANT	SMA1_MAIN	Sma connector
7	USB_V	J3	USB debug
8	USB_N	J5	USB debug
9	USB_P	J6	USB debug
10	POWER	LED1	LED indicator
11	STATUS	LED2	LED indicator
12	NET MODE	LED3	LED indicator
13	NET STATUS	LED4	LED indicator
14	GND	H2	ground
15	DBG_RX / DBG_TX	H2	Debug port
16	USB_BOOT	H0	programming mode
17	USB_BOOT	S3	programming mode
18	YT8512H	U1	FAST ETHERNET TRANSCEIVER

Functional Indication LEDs

POWER: Indicates that the evaluation board is powered on and receiving stable voltage.
STATUS: Indicates the module’s operation status.
NET MODE: Indicates the current registered network type
NET STATUS: Indicates the module’s network activity status.

Board Dimensions #

NEXUS EC200A-EU Modem dimensions — **Dimensions of the NEXUS EC200A-EU Modem : 94.20 * 57.95 mm**

What is QuecPython? #

QuecPython is a new platform from Quectel that uses MicroPython and allows programming Quectel’s IoT modules in Python. Its main goal is to help complete projects faster. Below is a list of modules that support this platform, which you can review:

**Region and network mode compatibility of QuecPython cellular modules**

Among the good features of this platform, one can point to support for various Quectel modules, diverse pre-built drivers, support for various communication protocols, and more. Additionally, like previous platforms, it has complete and comprehensive documentation. You can review more information about QuecPython from here.

Setting Up QuecPython #

To get started, we need to select a module and proceed with it. We are using the EC200A module and the Quectel EC200A module evaluation board, both of which you can purchase from the EICUT store. After that, it is necessary to download the driver for the EC200A module. To do this, go to the module’s information page on the QuecPython website, and from the downloads section, download the latest version of the driver and then install it.

Quectel EC200A-EU download page — **QuecPython USB driver download section**

The next step is to install the QPYcom software, which you should download from this link. This software is used for updating the module’s firmware, debugging, transferring files to the module, and more. Below is an image of the software’s interface:

🔗QPYcom software

Download from QPY

Now, using this software, we need to program the QuecPython firmware onto the module. To do this, go back to the EC200A module page on the website and download the module’s firmware.

Screenshot of Quectel EC200U series download page — **Download Quectel EC200U firmware**

Now, open the QPYcom software and go to the Download tab, then follow the steps below. Note that to select the firmware, you must first extract the downloaded firmware file from its compressed state and then select the file with the .blf extension. Also, after clicking the Download FW button, you need to reset the module for the download to start.

Screenshot of QPYcom V3.1.2 — **QPYcom steps for EC200U firmware flashing**

After the download is complete, go to the REPL tab and follow the steps below. Note that in the COM Port section, you should select the Quectel USB REPL Port, whose number may vary depending on your system.

QPYcom Serial Port Connection for Quectel Module — **Connect to Quectel module in QPYcom**

After opening the port, in the gray terminal environment, we can enter our Python commands. By pressing Enter, the commands are executed by the module, and the output is displayed to us. To start, we use Hello World.

QuecPython REPL Hello World on EC200A — **Output**

Now, let’s move on to controlling the status of one of the LEDs on the board that is connected to the NET_STATUS pin. To do this, first check the EC200A Hardware Design document to see which pin number NET_STATUS corresponds to on the module. Here, it is connected to pin 6.

Quectel EC200U module pinout diagram — **NET_STATUS (pin 6): GPIO output for network registration status**

Now, within this link, we examine that pin 6 of the module is recognized as which GPIO, which here is GPIO46.

Screenshot of Quectel EC200A pinout — **EC200A GPIO pinout**

Now, using the code snippet provided lower down on the same page, namely this one.

Screenshot of QuecPython documentation — **QuecPython GPIO control**

We wrote this code to be able to manually change the NET_STATUS state.

QuecPython Code #

from machine import Pin
gpio1 = Pin(Pin.GPIO46, Pin.OUT, Pin.PULL_DISABLE, 0)
gpio1.write(1)
sleep 1
gpio1.write(0)

from machine import Pin

gpio1 = Pin(Pin.GPIO46, Pin.OUT, Pin.PULL_DISABLE, 0)

gpio1.write(1)

sleep 1

gpio1.write(0)

FAQ #

What is the NEXUS EC200A-EU Development Board?

A powerful open-development board built around the Quectel EC200A-EU LTE Cat.4 module — supports 150 Mbps DL / 50 Mbps UL, QuecPython scripting, Ethernet LAN, diversity antenna, and full industrial-grade connectivity.

What are the main features of the EC200A-EU module?

• LTE Cat.4: 150 Mbps DL / 50 Mbps UL
• Global fallback: UMTS/HSPA+ + GSM/EDGE
• Built-in QuecPython support for rapid IoT scripting
• DFOTA over-the-air firmware updates
• Dual SMA antennas + diversity for better signal reliability

What connectivity options does the board provide?

• Ethernet LAN via YT8512H transceiver
• USB Type-C for power + data/debug
• Three SMA connectors: MAIN ANT, DIV ANT, GNSS ANT
• Nano SIM slot
• Debug UART pins (USB_BOOT, DBG_TX/RX)

What do the four status LEDs indicate?

• POWER: Board powered on
• STATUS: Module running
• NET MODE: Current network type (LTE/UMTS/GSM)
• NET STATUS: Network registration & data activity

How do I program QuecPython firmware?

Download firmware (.blf) from Quectel → use QPYcom software → select COM port → Download FW tab → press reset → wait for completion → switch to REPL tab for Python scripting.

Can I control GPIO pins with QuecPython?

Yes — example: control NET_STATUS LED (GPIO46) with:
from machine import Pin gpio = Pin(Pin.GPIO46, Pin.OUT) gpio.write(1) # LED ON

What is the board size?

Compact industrial design: 94.20 × 57.95 mm — rugged laser-engraved metallic housing for excellent heat dissipation and durability.

How do I enter USB download mode for firmware updates?

Press and hold USB_BOOT button (S3) while powering on or resetting → module enters DFU mode for QFlash or QuecPython firmware flashing.

Does it support Ethernet internet sharing?

Yes — built-in YT8512H Fast Ethernet transceiver + RJ45 port allows the board to act as a 4G-to-Ethernet router or share cellular internet via QuecPython scripts.