Programming a voice processor
 with a PC
NOTE: on this website, "voice processor,"
 voice processing system," and "VPS"
 mean the same thing.
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KX-TVA series Voice Processors

The KX-TVA50 and KX-TVA200 are usually programmed by a PC connected to the VPS with a USB cable. You can also connect your VPS to your Local Area Network, and program from any PC on the LAN that has the software loaded, or use a modem to program from a remote PC with a modem.

TVA VPSs CAN'T be programmed from a phone, but some adjustments can be done from a phone after the initial setup, even remotely. You need Windows software, which is supplied at no charge by Panasonic. It's on the CD-ROM that contains the manuals, packed with the VPS.

You'll also need USB drivers, which were not on the earliest KX-TVA CD-ROMS, but can be downloaded from

KX-TVS series Voice Processors
AbleComm's ProCables are great for programming and backing up Panasonic KX-TVS voice processors. CLICK to order
The KX-TVS series Voice Processors are programmed from a PC. They CAN'T be programmed from a phone, but some adjustments can be done from a phone after the initial setup, even remotely.

They do NOT need special software. You can use almost any general purpose PC communications software, such as Windows HyperTerminal, to access the software embedded in the voice processor. There's also a great Windows program. CLICK for info and free demo download of Voice Mail Master.

The installation manuals have diagrams for making a cable to connect a PC to the unit's serial port. It's easier to use an AbleComm ProCable or ProConnector Kit, or a serial cable and null-modem adapter from Radio Shack. The KX-TVS50, 75, 80, 90 and 95 have 9-pin connectors; the others have 25-pin connectors.

You can also use a Mac, with a basic Mac communications program.

If you can't connect:
  1. Make sure to set Flow Control to OFF or NONE.
  2. Make sure you have selected the proper serial port.
  3. Be wary of adapters that go from 9 pins to 25 pins and gender changers -- the fewer connections you have, the better your chances of successful connections.
  4. Try both 9,600 and 19,200 speeds.
  5. On Voice Processing Systems with rotary switches, shut power off, turn rotary switch from zero to one, turn power back on, turn rotary switch back to zero. (Thanks to Panasonic tech wizard Denton for this life-saver.)
  6. On Voice Processing Systems with DIP switches instead of rotary switches, shut off the power, move the "DIP" switches to right, left, left, left, turn the power back on, and move the switches to left, left, left, left. (Thanks to Frank at Panasonic for this.)                                           
  7. On Panasonic phone system control units, do a system clear and reset. (You will lose all programming and return to default settings.)
  8. Try another computer (really).

AbleComm's ProCables have been tested with all the Panasonic phone systems and voice processing systems we sell, using HyperTerminal, Programmator and VoiceMail Master. They are priced about $4 less than an equivalent cable and adapter from Radio Shack and about $13 less than the "wholesale" price charged by another company. CLICK to order online, or call 1 888 ABLE 999.
With AbleComm's new ProConnector Kit, you can program your phone system or voice processor up to about 60 feet away from the phone equipment closet (maybe even more feet -- we're not sure of the limit). The ProConnector-25 kit consists of specially wired adapters to convert from DB25 and DB9 to 8-pin ("RJ45") jacks. Our ProConnector-9 kit adapts two female DB9 connectors to RJ45, for use with the KX-TD308, KX-TA624 and KX-TVS50. You can use an RJ45 patch cord, or connect to data jacks and patch panels (568B wiring pattern.) CLICK to order online, or call 1 888 ABLE 999.

nulmodem.gif (7745 bytes)

There are many ways to construct a null-modem adapter or null-modem cable, and this situation drives us NUTS.

  • The Radio Shack #26-1496 25-pin null-modem adapter ($5.99, similar to photo at left) works fine with Panasonic phone system control units 99% of the time, and works fine with Panasonic voice processing systems 89% of the time. Use model 26-264 for the KX-TD308, and the smaller voice processing systems that have 9-pin connectors.

  • The Belkin null-modem adapter, available at Staples and many computer stores, such as CompUSA, works fine with the voice processing systems 99% of the time, but NOT with phone system control units. 

  • And to make things even worse, the Belkin adapter seems to work fine with HyperTerminal, but NOT with Voice Mail Master.

We are very pleased to share with you a wiring plan for making your own programming cable, developed by Debra Canfield. Debbie's design will allow you to use 8-pin "RJ-45" connectors, so you can program from a PC located many feet from the phone equipment, using normal 4-pair wire instead of a thick serial cable. Thanks very much, Debbie.
The following chart shows the 25 pin phone system or voice processor connector on the left and a 9 pin PC connector on the right.
SD 2 2 RD
RD 3 3 TD
SG 7 5 GND
DTR 20 6 DSR

This works with Windows HyperTerminal and Flow Control of None. Other settings are as described in the manuals or in the software.

In my case, I didn't really make a "cable." I configured modular RS232 to RJ45 connectors with the necessary pin configuration and attached the two with a 4 pair patch cord.

Once I had it tested and working that way, I changed it to what I really wanted. That is: In the wiring closet in our new addition where the telephone/voice systems are located, I attached modular RS232 connections to the telephone and voice systems. To those I attach an RJ45 to 4 pair 110 patch cord that I attach to a 110 block that is connected to a 110 block in my old wiring closet in the other part of the building. 

In the old wiring closet I used a 4-pair 110 patch cord to connect the new closet connection to a 110 block connected to an RJ45 outlet by my desk. At my desk I attached an 4 pair RJ45 cable from the RJ45 outlet to the modular connector in the back of my PC. Actually, I have one of the RJ45 outlets by my desk connected through to the telephone system and another to the voice system, so I just move the cord to whichever one I want to communicate with. This works great, but all people need to know is the pin configuration above. Then they can adapt it to their own situation.

By the way, I imagine you realize that the maximum length of the cable (stated at 6.5 feet in the telephone system manual) is nonsense. My total "cable length" is over 300 feet and includes 7 connections. Debra Canfield

If you are a masochist with a lot of time to kill and want to experiment, the charts below include the wiring recommendations from various sources.

VoiceMail Master      
Male DB25 Female DB25 Female DB9  
2 3 2  
3 2 3  
6 20 4  
7 7 5  
20 5, 6, 8 1, 6, 8  


Radio Shack      
Male DB25 Female DB25 Male DB9 Female DB9
1 1 4 1
2 3 3 2
3 2 2 3
4 5 6 & 1 4
5 4 5 5
6 & 8 20 4 6
20 6 & 8 8 7
7 7 7 8


Panasonic VPS      
Male DB25 Female DB25    
1 1    
2 3    
3 2    
6 20    
7 7    
20 5, 6, 8    




2004, 2005 AbleComm, Inc. All rights reserved. updated 3 JULY 05


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