If you are a licensed amateur radio operator using the GM950 for ham bands (144-148 MHz or 440 MHz), the community has preserved the CPS. Look for the Motorola CPS for Commercial Series (GM300, GM950, M10). The files are usually an ISO image (CD rips) labeled MOTOCPS_GM950.iso.
Crucial Note: Never try to use "Motorola Trunking" software or "MTSX" software on a GM950. You will corrupt the codeplug permanently.
Functional but ancient — works fine for hobbyists, frustrating for pros.
Recommendation:
Find GM950 CPS R01.01.00 from a trusted forum (e.g., Communications Support, P25.ca). Pair with a known good USB programming cable and a Windows XP virtual machine. Avoid “new” CD-ROM listings on eBay — they’re just burned copies of abandonware.
The most useful "new" feature for GM950 programming today is reliable USB-C programming + DOSBox automation — allowing a 2026 PC to program a 1990s radio without vintage hardware headaches.
Motorola GM950 is an legacy "N-series" mobile radio often used in professional and amateur radio contexts. While newer radios use modern Windows-based Customer Programming Software (CPS), the GM950 relies on older Radio Service Software (RSS), which was originally designed for DOS.
Programming this radio on contemporary computers requires specific hardware and software emulation to bridge the generational gap. Hardware Requirements
To establish a connection between the radio and a PC, you need: Programming Cable: A compatible cable, such as the RKN4081 Serial Cable Go to product viewer dialog for this item. or a modern USB equivalent like the MaxtonData RPC-MM-U
Radio Interface Box (RIB): Traditional setups use a physical RIB (e.g., Go to product viewer dialog for this item.
) to convert serial signals, though some modern USB cables have the RIB circuitry built-in.
Computer: A PC with a physical serial port is ideal, but a USB-to-serial adapter can work if configured correctly as COM1 in the Windows Device Manager. Software Ecosystem
The GM950 does not use standard modern Motorola CPS. Instead, it utilizes:
Radio Service Software (RSS): Versions like RSS R03.01.08 are typically required to read and write the "codeplug" (the radio's configuration file).
DOSBox Emulation: Because RSS is a 16-bit application, it cannot run directly on 64-bit Windows 10/11. Users often use DOSBox or a virtual machine running Windows 3.1/XP to provide a compatible environment. Programming Features
Once the software is running and connected, you can manage several key parameters: Motorola GM950 Serial Programming Cable RKN4081 DOS
For professionals who program multiple GM950s, nothing beats a dedicated, ancient laptop.
What you need:
Why this is "new"? It isn’t—but it’s reliable. Many shops still keep this "old new stock" hardware because it never fails. You can find these setups on eBay as "GM950 programming laptop" bundles.
Pros: 100% compatible, no emulation lag, direct serial control.
Cons: Heavy, slow battery life, transferring frequencies is tedious.
If you need to program one radio, buying software is overkill. Search for a "two-way radio shop near me." For $25-$50, they will load your frequencies using their legit, offline legacy computer. This is legally the only "new" solution that involves licensed software (they have perpetual licenses from decades ago).
The GM950 is part of Motorola’s "Maxtrac / GM300" logical family. The official software is Motorola GM950 RSS (Radio Service Software), version R04.00.00 or later. This software is not "Windows friendly." It requires:
Warning: USB timing issues may cause “Checksum error” or “Radio not responding”. Use FTDI adapter and disable USB power saving.