Spectra Programming - Serial Bus Error

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Spectra Programming - Serial Bus Error

Post by AJP402 »

Hello Again,

Every time I try to read or write to my Spectra, I get Serial Bus Error - only everything is hooked up fine!! Power to the comp, power to the Rib, power to the Radio - new cable from Comp to Rib and new cable from Rib to Radio - what could the problem be!?!?! I'm bordering on desperation. If anyone has any suggestions or any idea on "quirks" that Spectras may face when it comes to this issue, please advise! Thank you - Andy
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Re: Spectra Programming - Serial Bus Error

Post by Jim202 »

The first question I would ask, have you ever been able to read the radio? If this is a new radio to you? If so, it might have a configuration issue of how it was configuered last. Like did it come from one of the government systems and at the last configuration have a DES box connected to it. Did it have a siren box that has been removed? Is it one of the HHCH mic units that needs a SIU box?

Give us some more info to try and help you.

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Post by elkbow »

I can tell you something right away that may be your problem....are you using a Motorola factory RIB? Spectra's are cranky on aftermarket ribs. Also, give us some more details, are you using a slow computer (what make, model, speed?). Are you using factory cables or aftermarket cables? Are you running from DOS and not from the Windows DOS?
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Post by John G »

This may seem stupid but it happened to me once the first time I used a program. Make sure you have selected the serial port you have the RIB connected to. . Does the radio work OK? Does the same computer , RIB, and cable, or at least computer and RIB , work on other radios? I have never had a problem with computer speed with Spectras but just had one with a MTSX2K and it acted just like the radio wasn't connected.
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Post by AJP402 »

Hello again,

Thank you for all the prompt responses. Here we go:

1) The computer I'm using is fairly slow, an old Gateway. I run the program in DOS.

2) I use a Polaris Rib, but did try an official Motorola RIB, no luck. The cables are "no-name"

3) I was able to Read from and Write to the computer just before this condition started. All of a sudden, "Serial Bus Error" - I didn't do anything different.

On my most recent attempt, it didn't said Serial Bus Error: Power Failure - but everything was powered. Would the draw from the car battery effect the programming if it could draw enough power for whatever reason? Should I pull the radio out and try a power supply?

Thanks for any and all assistance!!! - Andy P.
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Post by natedog224 »

First off FYI for others : If the radio came from a system that had an ASN box programmed in it would tell you "unable to read ASN" instead of a serial bus error when you read it.

Second : Since the problem wasn't there at first I would check your programming cable for a bad wire ect. Also if the connector has some screws lock them down at the rib end and at the spectra end if its a high power radio. I have seen this happen with my own cable before so it wouldnt surprise me.

Third : I had a rouge spectra blow a diode on my SmartRIB on the busy line making the RIB seem ok but actually be very dead. The radio even worked fine by itself oddly enough. Try another radio on the setup. Preferably a different type like a jedi handheld or something. Then try a different Spectra to determine wheter its a radio problem.
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Post by Monty »


If you do a search, you should be able to find
more information, but I will give you some following

Just because you were able to program your radio
once with your current set up does NOT mean it will
work everytime.

As a Motorola Tech, I am seeing these programming
errors almost on a day to day basis.

Anyhow, you " MUST " have a stable program platform,
and having the " Right " equipment is a step in the right

1. Although you may not want to hear it, Polaris Ribs are
pretty bad in my opinion. Yes, I have seen the exact same
thing ! where they worked fine on moment, and not the next.

Your problem could be as simple as " A LOW BATTERY "

Make sure you have a Fresh Battery !

Even though the Motorola Rib can get its power from the
Spectra, Clones do not have this feature. Play it safe, get
a Motorola Rib Box.....At least you will have the assurence
that is working. USe a Fresh Internal Battery AND External
Power !

Also , BEWARE of Clone Cables ! If you have a Clone Cable
where the wires are loose in and around the DB25 Shell, perhaps
one of your wires is broken ( or gets shorted ) which could
cause a MAJOR FAILURE in the radio.

Its not worth blowing your radio up over a cable that
was thrown together in 5 ~ 10 min.

There is few persons around that are making cheap and horrible
cables, and I have seen where these cables have blown up the
radio as well.

If your Cable looks the one in the photo, get rid of it !


Anyhow, getting past the Cable / Rib / Battery issue, you
should also make sure your COM Port is set up and working.

If you can find a Program called [ Whatport.Com ] you can install
it on your computer ( its free ) and you can tell if the RS-232 Port
is working.

Rare, but sometimes in the BIOS ( if the Bios battery gets weak )
the internal Bios settings may have changed.

Anyhow, other than perhaps corrupted Software ( which happens
from time to time ) you might want to re-install the Software
if you have confidence in your Rib and Cable.

Spectras ( other than the X9000 ) use FULL FEATURES of the RIb
Box, and not all computers have the exact same protocalls...Although Close, you will find a few memebers [ Will is one of them ] that have explored the RS-232 protocall issues pretty well......As a long term tech, I just stick with Proven Products to save me the headaches you are encountering.....And perhaps
a hefty service bill in the event your radio gets damaged either
by a Clone Cable or Rib....

Will has his ideas, and feels modifying the Ribs is a better approch !

With me, I sorta stay with the old school of thought especially
if it works ! Murphys Law sorta speak.

I would take a look at the Cable ( Inside ) a.s.a.p, as your probelm
could be there as well if the Motorola Rib U used was OK....

Hope I have been able to shed some light on your problem.


Also, MAKE SURE you are using DOS 6.22 ( AND DO NOT ) try
and use DOS under a Windows Application !

Forgot to mention that....Only Exception ? is you are deep into
the Operating Systems of all the Windows OS's and how to get
around them.

Need help on a Program Cable or (/\/\) Rib Box ?
Contact me anytime/All availible / Free Support Info !

mail to: MSisco9939@aol.com
PLease avoid PM's whenever possible. Box gets too full.
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Re: Spectra Programming - Serial Bus Error

Post by kb4vwa »

Is there a way to program a Spectra with Windows XP? I cannot remember if this possible, I get error when testing comports. no communication. I tried Molslo, etc, nothing.
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Re: Spectra Programming - Serial Bus Error

Post by Satelite »

I just looked up on my list of motorola programs and according to it astro spectra plus rvn4186t which contains rvn4181 and rvn4185 which is software programming version r06.00.00 and works with win98 = me= nt = 2000 = and also xp windows.

Theres also a spectra railroad program that is DOS only rvn4099 which is software programming version r04.05.01

Maybe check your software version see if its correct for windows xp

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Re: Spectra Programming - Serial Bus Error

Post by Jim202 »

I program Spectra radios all the time with a computer I have that runs DOS only for the Spectra and several other radios.

Do not try to run a DOS box under a computer running Windows. It probably won't function with the Spectra software very well. I use DOS only to program Motorola radios of this age.

The other suggestion I will pass along is to download a program called: CACHEOFF.COM. Do a search on the Internet and download it.

Put it in the same directory as each of your different radio software files. Then start the CACHEOFF.COM program before you start the radio program like the Spectra program RSS. It should help resolve some of the timing issues that crop up. I can vouch on this personally.

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Re: Spectra Programming - Serial Bus Error

Post by Jim202 »

I know this is a really old posting, but did you ever get your radio programmed?

If so, let the rest of the group know what you had to do to get the programmimg to work.

Another commement I will pass along, is that the DOS computer should have a clock speed of no more than about 900 MHz.

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