OpenGD77 CPS
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OpenGD77 CPS BETA
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Codeplug Overview

0
Channels
0
Zones
0
Contacts
0
TG Lists
0
Satellites

Quick Actions

My Saved Codeplugs

No saved codeplugs

Log in to save and access your codeplugs from any device

General Settings

Displayed on radio boot screen (max 8 chars)

Channels

# Name Type RX Freq TX Freq CC/Tone TS Contact Power Actions

No channels yet

Contacts / Talk Groups

Name ID Type TS Override Actions

No contacts yet

TG Lists (RX Groups)

# Name Contacts Contact List Actions

No TG lists yet

Zones

# Name Channels Channel List Actions

No zones yet

VFO A/B Settings

VFO A

CTCSS (e.g. 88.5) or DCS (D023N, D023I)
CTCSS (e.g. 88.5) or DCS (D023N, D023I)
'Disabled' or 1-10
0 = Disabled, 15-495 in 15s steps

VFO B

CTCSS (e.g. 88.5) or DCS (D023N, D023I)
CTCSS (e.g. 88.5) or DCS (D023N, D023I)
'Disabled' or 1-10
0 = Disabled, 15-495 in 15s steps

DMR ID Database

Current Database

Database is cached on our server and updated daily. Select countries to filter, or leave as "Worldwide" to load all.

0 IDs Loaded
Never Last Updated

Storage Options

Configure data format for writing to radio. Records include callsign, name, city, and country (compressed).

Store more IDs by using voice prompt flash region (MK22 radios only)
0 Max Contacts
0 Bytes/Record
DMR ID Callsign Name City Country Actions

APRS Configuration

Name SSID Via Path Icon Comment Actions

No APRS configurations

DTMF

DTMF Settings

DTMF Self ID (0-9, A-D, *, #)

DTMF Contacts

Name Code Actions

No DTMF contacts

Satellite Frequencies

Satellite tracking for OpenGD77 radios.

Configure satellite frequencies, CTCSS tones, and update TLE (Two-Line Element) orbital data for amateur radio satellites.

Supports: AO-91, AO-123, IO-86, ISS, LilacSat, POEM 4, PO-101, SO-50, SO-124, SONATE-2, UmKA-1, and custom satellites.

Cat # Name RX1 (MHz) TX1 (MHz) CTCSS Arm CTCSS RX2 (MHz) TX2 (MHz) RX3 (MHz) APRS TLE Actions

No satellites configured

Click "Load Defaults" to add common amateur radio satellites

UK Repeaters

Callsign Name/QTH Type TX Freq RX Freq CTCSS/CC Locator Status

Loading UK repeaters...

DMR Repeaters

Callsign City Country TX Freq RX Freq CC Network Status

Loading DMR repeaters...

World Repeater Map

Operational Not Operational DMR Repeater

Click on the map to set a centre point for the import radius. Only repeaters within the selected radius will be imported. Duplicates are automatically skipped.

Import CSV

Channels

Import channels from CSV file

Contacts

Import contacts/TGs from CSV

Zones

Import zones from CSV file

TG Lists

Import TG lists from CSV

CHIRP / Frequency JSON

Import from CHIRP CSV or frequency JSON (DMR & NFM only)

RadioReference Import

Login to RadioReference

Enter your RadioReference.com account credentials. Your credentials are sent securely to the server for API access but are never stored.

Scan Lists

Name Channels Priority Ch1 Priority Ch2 Actions

No scan lists

Shared Library

Community Codeplug Library

Browse and download codeplugs shared by the OpenGD77 community. Preview codeplugs before copying them to see channels, zones, and contacts.

Loading shared codeplugs...

My Codeplugs

Your Saved Codeplugs

Your personal codeplug library stored on the server. Access your codeplugs from any device by logging in.

Loading your codeplugs...

Boot Settings

Display Options

Choose what displays on boot

Security

6-digit numeric password

Boot Image

128x64 pixels, 1-bit


Boot Melody

Comma-separated note/duration pairs. Format: note1,duration1,note2,duration2,... (0,0 ends the melody)

Band Limits

VHF Band

UHF Band

Band limits define the allowed frequency ranges for transmission. Values are in MHz.

Theme Editor

OpenGD77 supports separate day and night themes. Edit each independently.

Core Colors

Boot Screen

Menu Colors

Notifications

Channel/VFO Screen

Signal Bars

Satellite/GPS

Live Preview

Theme Library

Loading themes...

Radio Tools

Screen Grab

Download a screenshot from the radio display.

Voice Prompts

Select from library or upload your own voice prompts.

Backup Flash

Create a full backup of the radio flash memory.

Restore Flash

Restore flash memory from a backup file.

Backup Registers

Backup secure registers from the radio.

Calibration

Backup or restore radio calibration data.

Firmware Update

Update OpenGD77 firmware on your radio.

Put your radio into DFU mode before uploading firmware:

  • MK22 (GD-77, DM-1801, RD-5R): Press and hold SK1 + SK2 while turning on
  • STM32 (MD-UV380, MD-9600, MD-2017, DM-1701): Hold PTT + top side key while turning on

Warning: Incorrect firmware can brick your radio. Only use official OpenGD77 firmware files.

MK22 Radio Firmware

GD-77, DM-1801, RD-5R, GD-77S

Select firmware version or upload your own file for MK22-based radios.

Language pack will be uploaded after firmware
Using built-in donor file: GD-77_V4.3.6.sgl
Official Radioddity firmware for DMR codec support

STM32 Radio Firmware

MD-UV380, MD-9600, MD-2017, DM-1701

Select firmware version or upload your own file for STM32-based radios.

Language pack will be uploaded after firmware
Using built-in donor file: MD9600-CSV(2571V5)-V26.45.bin
Original TYT firmware for DMR codec support

CPS User Guide

Everything you need to know to get started with the OpenGD77 CPS

Welcome to OpenGD77 CPS!

The OpenGD77 CPS (Code Plug Studio) is a free, web-based tool that lets you program your radio directly from your browser. No downloads or installations required!

Works in your browser - no software to install
Compatible with Chrome, Edge, and Brave browsers
Supports MK22 radios (GD-77, DM-1801, RD-5R) and STM32 radios (MD-UV380, MD-9600)
Save and share your codeplugs with the community

What's in This Guide

Getting Started Connecting Your Radio Interface Overview Working with Channels Organizing Zones Contacts & Talkgroups Importing Data Saving Your Work Troubleshooting

Getting Started

Before you can program your radio, you'll need a few things:

A Compatible Browser Google Chrome, Microsoft Edge, or Brave. (Firefox and Safari don't support USB connections.)
A USB Cable The cable that came with your radio, or any compatible USB cable.
Your Radio with OpenGD77 Firmware Your radio must have OpenGD77 firmware installed. Check the Firmware Update section if you need to install it.
WinUSB Driver (Windows Only) Windows users need to install a special driver. See the USB Setup guide for instructions.

Connecting Your Radio

Follow these simple steps to connect your radio to the CPS:

1
Select Your Radio Type

Use the dropdown at the top of the screen to choose your radio type:

  • MK22 - For GD-77, DM-1801, and RD-5R radios
  • STM32 - For MD-UV380, MD-9600, and similar radios
2
Connect the USB Cable

Plug your radio into your computer using the USB cable. Make sure the radio is turned ON.

3
Click the Connect Button

Click the Connect button in the top toolbar.

4
Select Your Device

A popup will appear showing available USB devices. Select your radio from the list and click Connect.

5
You're Connected!

The status indicator at the top will turn green when connected. You can now read from or write to your radio!

Tip: If your radio doesn't appear, see the USB Setup guide for troubleshooting steps.

Interface Overview

The CPS is organized into three main areas:

Sidebar (Left)

Navigate between different sections of your codeplug. Click any item to open that section.

Toolbar (Top)

Contains your most-used actions:

  • Connect - Connect to your radio
  • Read - Read the codeplug from your radio
  • Write - Write the codeplug to your radio
  • Open - Open a codeplug file from your computer
  • Save - Save your codeplug as a JSON file
  • Export - Export as G77 binary file
Main Content (Center)

This is where you'll edit your channels, zones, contacts, and other settings. The content changes based on which section you select from the sidebar.

Working with Channels

Channels are the heart of your codeplug. Each channel stores a frequency, name, and other settings for a repeater or simplex frequency.

Adding a New Channel

  1. Go to the Channels section in the sidebar
  2. Click the Add Channel button
  3. Fill in the channel details:
    • Name - A friendly name (up to 16 characters)
    • RX Frequency - The frequency to receive on
    • TX Frequency - The frequency to transmit on (same as RX for simplex)
    • Mode - FM for analog, DMR for digital
  4. Click Save to add the channel

Editing a Channel

  1. Click on any channel in the list to select it
  2. Edit the fields you want to change
  3. Your changes are saved automatically

DMR Channel Settings

When you set a channel to DMR mode, additional options appear:

  • Color Code - Must match the repeater (usually 1)
  • Time Slot - TS1 or TS2, as required by the repeater
  • Contact - The default talkgroup or contact for this channel
  • TG List - A list of talkgroups you can access on this channel
Tip: You can quickly import channels from repeater databases using the Import section!

Organizing Zones

Zones are folders for your channels. They help you organize channels into logical groups - for example, by location, band, or use case.

Creating a Zone

  1. Go to the Zones section in the sidebar
  2. Click Add Zone
  3. Give your zone a name (e.g., "London Repeaters", "2m Simplex", "DMR Nets")
  4. Add channels to the zone by selecting them from the list

Why Use Zones?

  • Quick Access - Switch between groups of related channels easily on your radio
  • Organization - Keep hundreds of channels manageable
  • Favorites - Create a zone with your most-used channels for quick access
Tip: You can add the same channel to multiple zones. Create a "Favorites" zone with your most-used channels from all areas!

Contacts & Talkgroups

Contacts are used for DMR (digital) communication. They can be individual DMR users or Talkgroups (group calls).

Types of Contacts

Talkgroups (TG)

Group conversations - like a radio "chat room" that multiple people can join. Most DMR activity uses talkgroups.

Private Contacts

Individual DMR users you can call directly using their DMR ID.

TG Lists

A TG List is a collection of talkgroups you can access on a channel. When you assign a TG List to a channel, you can switch between those talkgroups while on that channel.

Importing Talkgroups

You can import talkgroup lists directly from various DMR networks using the Import TGs button in the TG Lists section. Supported networks include:

  • TGIF - TGIF Network talkgroups
  • Brandmeister - Brandmeister network talkgroups
  • System X - System X talkgroups
  • FreeDMR - FreeDMR Worldwide and UK talkgroups
  • DMR+ - DMR+ network talkgroups
  • ADN Systems - ADN Systems talkgroups
  • FreeSTAR IPSC2 - FreeSTAR IPSC2 talkgroups
  • QuadNet - QuadNet talkgroups

Common Talkgroups

Here are some popular worldwide talkgroups:

  • 91 - Worldwide
  • 235 - UK nationwide
  • 310 - USA Tac 310
  • 9 - Local area
Tip: You can download the DMR ID database in the DMR ID Database section to see callsigns on your radio when you receive calls!

Importing Data

Save time by importing data from various sources:

UK Repeaters

Import repeater data directly from the RSGB database. Select your area and import local repeaters with one click.

DMR Repeaters

Search and import DMR repeaters from the Brandmeister network. Includes talkgroups and settings.

Repeater Map

Visual map showing repeaters near you. Click on any marker to view details and add it to your codeplug.

Import CSV

Import channels, contacts, or zones from CSV spreadsheet files. Useful for migrating from other CPS software.

Shared Library

Browse codeplugs shared by other users. Find pre-configured setups for your area or radio.

Saving Your Work

There are several ways to save your codeplug:

Save Options

Write to Radio

Send your codeplug directly to your connected radio. This is the most common way to save your work.

Button:
Save as JSON

Save a JSON file to your computer. This is a text-based format that's easy to backup and share.

Button:
Export as G77

Export a G77 binary file. This format is compatible with the original desktop CPS software.

Button:
Save to Cloud

If you're logged in, you can save your codeplug to the cloud and access it from any device.

Via: My Codeplugs
Important: Changes are not saved automatically! Make sure to save your work before closing the browser.

VFO A/B Settings

VFO (Variable Frequency Oscillator) mode lets you manually tune to any frequency without using preset channels.

What is VFO Mode?

Your radio has two VFOs: VFO A and VFO B. Think of them as two scratch pads where you can dial in any frequency on the fly.

When to Use VFO

  • Trying out a new frequency before saving it as a channel
  • Scanning across a band to find activity
  • Quick QSOs without setting up a permanent channel

Setting Up VFO Defaults

In the VFO A/B section, you can configure the default settings for each VFO:

  • Frequency - The starting frequency
  • Mode - FM or DMR
  • Power - Transmit power level
  • Step Size - How much the frequency changes when you turn the dial

APRS Settings

APRS (Automatic Packet Reporting System) lets your radio send your location and other data over the air.

Setting Up APRS

  1. Go to the APRS section in the sidebar
  2. Enable APRS and enter your callsign with SSID (e.g., M0ABC-7)
  3. Set your symbol (usually a handheld radio icon for portable operation)
  4. Configure the beacon interval (how often your position is sent)
  5. Optionally add a status text

Common SSID Numbers

  • -7 - Handheld
  • -9 - Mobile
  • -1 - Home station

General Settings

The General Settings section contains important radio-wide options:

Key Settings Explained

  • DMR ID - Your unique digital ID number (required for DMR operation)
  • Callsign - Your amateur radio callsign
  • Radio Name - Displayed on your radio's screen
  • Timeout Timer - Automatically stops transmitting after a set time
  • Scan Mode - How the radio behaves when scanning
  • Squelch Level - Adjusts sensitivity to weak signals
Tip: If you don't have a DMR ID yet, you can get one for free at radioid.net

Boot Settings

Customize what appears on your radio's screen when it starts up:

  • Boot Screen Text - Custom text shown at startup (usually your callsign)
  • Boot Image - Some radios support a custom boot image
  • Boot Sound - Enable or disable the startup sound
  • Intro Screen Duration - How long the boot screen is displayed

Theme Editor

Personalize your radio's display with custom colors and themes!

What You Can Customize

  • Background colors
  • Text colors
  • Menu highlighting
  • Battery indicator colors

Using Pre-made Themes

The Theme Editor includes several pre-made themes you can apply with one click. Choose from dark, light, colorful, and retro styles.

Troubleshooting

Having problems? Here are solutions to common issues:

Radio won't connect
  • Make sure the radio is turned on
  • Try a different USB cable
  • Windows users: Install the WinUSB driver (see USB Setup)
  • Make sure you're using Chrome, Edge, or Brave browser
Read/Write fails halfway through
  • Don't touch the radio or cable during transfer
  • Try a shorter or higher quality USB cable
  • Restart both the radio and browser
Browser doesn't show USB popup
  • Only Chrome, Edge, and Brave support WebUSB
  • Firefox and Safari won't work - switch browsers
  • Make sure you're not in private/incognito mode
Channels don't work on the radio
  • Double-check your frequencies are correct
  • For DMR: verify the Color Code and Time Slot
  • Make sure you have a contact/TG assigned to DMR channels
  • Check that the channel is added to a zone
DMR contacts not showing callsigns
  • Download the DMR ID database (in the DMR ID Database section)
  • Make sure you write it to the radio after downloading
Still stuck? Click the Feedback & Bugs button in the sidebar to report an issue or ask for help!

Quick Reference

Handy tips for power users:

Pro Tips

  • Backup regularly - Save your codeplug to a file before making major changes
  • Use zones wisely - Group channels by location or purpose for easier navigation
  • Test before committing - Read your radio's codeplug first to make sure connection works
  • Cloud save - Log in to save your codeplugs to the cloud and access them anywhere

USB Setup Guide

About USB Connections

The OpenGD77 CPS uses WebUSB to communicate directly with your radio from the browser. On Windows, you need to install the WinUSB driver using a tool called Zadig so that the browser can access the radio's USB interface.

This is only required on Windows. Linux and macOS typically work without additional driver setup.

Download Zadig

  1. Visit https://zadig.akeo.ie/
  2. Download the latest version of Zadig
  3. Run the downloaded executable — no installation is required
Zadig Options menu showing List All Devices

Install WinUSB Driver

  1. Connect your radio to your computer via USB and turn it on
  2. Open Zadig
  3. Go to Options → List All Devices
  4. Select your radio from the dropdown list (look for OpenGD77 or similar)
  5. Ensure the target driver on the right is set to WinUSB
  6. Click Replace Driver (or Install Driver if no driver is currently installed)
  7. Wait for the installation to complete — you should see a success message
Zadig showing the target device selected with WinUSB driver
Zadig showing driver installation success

Connect in CPS

  1. After installing the WinUSB driver, click the Connect button in the CPS header
  2. Your browser will show a popup asking you to select a USB device
  3. Select your radio from the list and click Connect
  4. The radio status indicator should change to show the radio is connected
Chrome WebUSB dialogue showing device selection

Reverting to the Original Driver

If you need to use the radio with other software (such as the original desktop CPS), you can switch back to the original driver using Zadig:

  1. Open Zadig
  2. Go to Options → List All Devices
  3. Select your radio from the dropdown list
  4. Change the target driver to USB Serial (CDC)
  5. Click Replace Driver

You can use the same process to switch back to WinUSB when you want to use the web CPS again.

Zadig showing USB Serial (CDC) driver selection for reverting

Troubleshooting Tips

  • Radio not appearing in Zadig? Make sure the radio is turned on and connected via USB. Try a different USB cable or port.
  • Browser not showing the USB popup? Ensure you are using a WebUSB-compatible browser such as Google Chrome or Microsoft Edge. Firefox and Safari do not support WebUSB.
  • Connection fails after selecting the device? Try unplugging the radio, waiting a few seconds, and reconnecting. Then click Connect again.
  • Wrong driver installed? Open Zadig again, select the device, and ensure WinUSB is selected as the target driver, then click Replace Driver.

OpenGD77 User Guide

Comprehensive documentation for OpenGD77 firmware

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