Introduction to EG91X Evaluation Board

Supported Module List

• EG915U

Feature List

Basic Overview

The QuecPython_EG91X series C1-P02 evaluation board is a compact and portable "pocket-sized" board designed specifically for QuecPython.

The main equipped modules are the EG915U series LTE Cat 1 wireless communication modules, which are also compatible with Quectel's EG91 series, EG95 series, BG95 series, and BG96 modules in terms of packaging. This allows for seamless switching between 2G and 4G networks to meet the application requirements of different industries.

The evaluation board has a built-in Type-C interface, making it convenient for development. Developers only need a USB Type-C cable to easily use the evaluation board.

Additionally, the evaluation board is compatible with the expansion board of Raspberry Pi Zero, which can be directly used on the evaluation board.

Evaluation Board Resources

Function Description

The main component and interface placement of the evaluation board is shown in the following figure:

Evaluation board dimensions:

The main pin placement of the evaluation board is shown in the following figure:

Note
For more information about the evaluation board, please visit https://python.quectel.com/en/resource-download?cid=252.

Evaluation Board Configuration

The detailed assignment of the peripheral interfaces on the evaluation board is as follows:

The evaluation board has 5 functional indication LEDs, as follows:

• P21: Power indication LED.
• PSM: Module Pin 1, PSM indication LED.
• SCK1: SIM1 detection indication LED, lights up when SIM1 is inserted.
• SCK2: SIM2 detection indication LED, lights up when SIM2 is inserted.
• PWR: Power indication LED.

The positions of the above indication LEDs refer to the silkscreen on the top of the evaluation board mentioned in the previous text (the side where the module is located is the top).

Evaluation Board Interfaces

Pin Assignment of 10-Pin Header

• 1 & 2: Auto turn on
• 3 & 4: Provide power externally when connected and test power consumption when disconnected
• 5 & 6: Connect DCDC to power the module
• 7 & 8: Enable SD power supply
• 9 & 10: Enable GNSS active power supply

When testing power consumption, make sure to switch off the USB power supply switch (USB_ON/OFF) on the back of the evaluation board.

Singular-pin Assignment of 40-Pin Header

Quick Start Guide

Hardware Preparation

• Step 1: Required Items

  • Development board
  • USB-C cable (A-to-C)
  • Windows 10 PC
  • Nano-SIM card
  • 4G antenna

• Step 2: Antenna & SIM Installation

  • Attach the provided antenna to the MAIN antenna port.
  • Insert the SIM card into the Nano-SIM slot.

• Step 3: Connect the Board

  • Power the board via USB-C.

• Step 4: Power On

  • Press and hold PWK until the power indicator light on the mainboard (labeled as POW) lights up.
  • If you short-circuited PWK_ON, there's no need to press PWK; the board will power on automatically.

  If the PWR indicator is constantly on, the EVB is successfully turned on.

Driver Installation

1. Download the QuecPython USB Driver from QuecPython Official Drivers.
2. Extract and run setup.exe or setup.bat.
3. Verify installation in Device Manager (look for "Quectel USB" ports). Ignore unrelated devices like "Mobile ECM Network Adapter."

Tool Installation

1. QPYcom: Download from QuecPython Tools. Extract and use directly.
2. VSCode Plugin: Search for "QuecPython" in the Visual Studio Code marketplace.

Firmware Burning

1. Firmware Download: Get the latest QuecPython firmware from QuecPython Firmware Page.

2. Burning Steps:

   • Open QPYcom, select the USB REPL port, and create a new project.

   • Choose the .bin firmware file

   • Set mode to "Download FW" and click Download.

REPL Debugging

1. Connect via QPYcom and open the REPL interface.
2. Test with print("Hello World!").

First Script Development

Writing a Script

Create helloworld.py:

print("Hello World!")

File Transfer

• Method 1: Drag-and-drop files via QPYcom’s GUI.

• Method 2: Use the "Download Script" feature in QPYcom.

Running Scripts

Execute via REPL:

import example
example.exec("/usr/helloworld.py")

Stopping Program Execution

How to stop a running program. The following methods are provided according to the type of the running script file:

Low Power Consumption Testing Guide

The EG915U module supports multiple operating modes, each with distinct power consumption characteristics. The common operating modes are as follows:

ACTIVE: The module is engaged in LTE data transmission, GSM calls, or executing RTOS logic. Power consumption varies significantly depending on specific tasks and network communication standards, as both CPU power usage and RF power levels differ across scenarios.

IDLE: The module is in an idle state with hardware fully powered and RTOS running, but no active threads. It resumes operation immediately upon task initiation or incoming network activity. ECX00U series modules reduce clock frequency in IDLE mode, entering a light sleep state (disabling high-speed clocks while keeping the CPU active).

Sleep: Sleep mode requires the module to be idle with autosleep enabled. In this mode, RTOS pauses, clock frequency slows, and peripheral controllers (UART, SPI, etc.) are powered down, retaining only essential interrupt controllers to minimize power consumption.

PSM: PSM (Power Saving Mode) is a 3GPP-defined low-power mode where the module periodically wakes to perform tasks and remains in PSM sleep otherwise. During PSM sleep, behavior and power consumption resemble a powered-off state.

Power Off: The module is fully powered down, with baseband chips and peripheral controllers disabled (PMIC remains active). It can be awakened via Powerkey or RTC alarm.

Test Preparation

• Step 1: Hardware Setup

  Prepare the following components before starting:

  1. Development Board
  2. USB Cable (USB-A to USB-TypeC)
  3. PC (Windows 10)
  4. SIM Card
  5. 4G Antenna
  6. Power Monitor Mini

• Step 2: Antenna & SIM Card Installation

  Install the provided antenna into the MAIN antenna socket and insert the SIM card into the development board's SIM slot.

• Step 3: Board Connection

  Connect the development board's Type-C port to the PC using a USB Type-C cable. Attach the power monitor's positive lead to MODULE_EN's Vbat (refer to BG95 User Guide) and the negative lead to the module's GND. Connection diagram:

  

  Important!
  Remove all jumper caps during measurements to avoid external interference.

Power Consumption Measurement

Power-Off Current

With the board connected via USB Type-C, power off the module by disabling USB_VBus (set USB switch to "off" on the board's rear). Measure the current while the module is inactive (output pins pulled low/floating). Average current remains stable at microampere levels.

Idle Current

After power-off measurement, press and hold Powerkey to boot the module (default: IDLE mode). The module remains idle with RTOS running but no active threads, ready to resume instantly for tasks or calls.

Sleep Current

With autosleep enabled during idle, the module enters sleep mode by deactivating non-essential IP cores (peripherals/interrupts) and reducing clock frequency.

1. Re-enable USB_VBus.

2. Open QPYcom Tool and execute:

   import pm
   pm.autosleep(1)  # Enable autosleep
   

   

3. Disable USB_VBus again (switch to "off").
   API Reference | Details

4. Sleep current shows periodic spikes:

   

PSM Current

To enable PSM:

1. Request PSM from the base station (via ATTACH/TA_UPDATER with timer parameters).
   • Note: Base station determines final timer values.
2. Once ACT timer expires in IDLE, the module shuts down CPU/RF (partial power-off), retaining wake-up sources (ACT/TAU timers, PSM_INT).

Steps:

1. Enable USB_VBus.

2. In QPYcom:

   pm.set_psm_time(tau_uint,tau_time,act_uint,act_time)   # Configure PSM
   

   

3. Disable USB_VBus.
   PSM Guide | API

PSM baseline current (µA-level, similar to power-off):

Notes:

• Confirm carrier support for PSM and configure compatible network standards (this test uses catM).
• Additional guidance.