The PR1 is a very popular Digitrax product, and is used not only by Digitrax system users, but all DCC users. As an offline service mode programmer, it is not system related, it does not even connect to the system. All it needs is a computer, power source, and a piece of track.
Most people generally do not have problems
getting the PR1 to work properly. But there are those few who do.
That
is what this page is for, to help those who are having a problem with PR1.
I always recommend using 2 - 9 volt batteries in series with a PR1 for anyone who is
having problems getting their PR1 to work. It removes 2 of the possible
variables. The PR1 is sensitive to AC ripple and voltage, there is no ripple with
batteries, it is as pure DC as it is going to get. And the voltage is just
about right.
For those who need to know, the AC ripple needs to be less then 0.1V under full
load.
For best results use the PR1 with a voltage supply of about 16 - 18 Vdc. If the
voltage is significantly lower or higher than the specified range, the PR1 may
not be able to correctly READ the programmed values. However, programming
[WRITE] functions will work properly in a voltage range from about 12 to 20 Vdc.
There is nothing at all wrong with using an AC to DC converter, wall wart, etc.
But if someone is having a problem getting the PR1 to work, then the best place
to start is go with two fresh 9 Volt batteries in series, this removes the variables of how
much ripple is in the supply, and what voltage is it supplying.
I use a Radio Shack adapter model #273-1652D 500mA at 12vdc with a 1000uf
35v Electrolytic Capacitor across the output. This supply puts out 17Vdc with no
load, with the full load of the PR1 it still outputs 16.5 Vdc.
Note this supply
will not allow the PR1 to read properly without the capacitor across the output.
I also use 2 - 9 volt batteries in series with the PR1 I keep with my lap top, as it is as
portable as it can get. And the batteries I usually use with it are over a year
old before they even get hooked to my PR1. They are the ones from my throttles
and smoke detectors that I change every year. There is very little drain from
the PR1, not the no load voltage from the wall wart to full PR1 load above. I
guess I will have to check the idle current of the PR1, but the full max is less
then 200mA and that is only when the decoder is
ACK'ing and sinking current, in the form of pulses.
If one just un-plugs the CC2 cable from the rear of
the PR1, the batteries are effectively disconnected. Of course one can also add
a switch or just un-plug the batteries, but removing the CC2 cable is just as
effective.
As far as battery life, that is a hard call. I find pending how much programming
I am doing, I can get from 6 months to a year on them. Remember these batteries
are already past their useful life in throttles and smoke detectors, so I look
at them as free any ways.
Again, there is nothing wrong with using an converter, wall wart, what ever.
But not a good choice for someone who is having problems, the best choice here
is the 9V batteries in series. Then once the problems have been figured out, if you so
choose, by all means go with a converter. But at least now if the PR1 stops
working properly, you know it is either a ripple problem or voltage problem as it
works with the 16+ Volts of the batteries pure DC.
Most modern day computers and laptops only have a 9 pin DB9 serial port, the PR1
is a standard 25 pin DB25 device. So you may need an adapter. If so you
need to make sure you get the proper adapter. You use a DB9(female) to
DB25(male) adapter. But you need to make sure this is a comm. or serial adapter.
Gender changers and mouse adapters, etc do not work. Also note the proper
adapters are sold in two styles, those with a cable connecting the DB9 to a DB25
on the other end of the cable, as well as a single solid device with a DB9 and
DB25 as a one piece unit. I would recommend the one piece unit. It has been
found that the cable type can cause problems. I ran in to this on my laptop. The
cable type will not work with it and the PR1, but the solid type does. But also
on the same note, that cable one will work on all my desktop systems. If you do
have to go with one with a cable get one with as short of cable as possible.
Now for those who may want to build their own adapter or may be check the one
they have for proper pin out.
Use this to build your own, or use an Ohm meter or continuity tester to check
the pin out from one side to the other to verify you have a proper adapter.
Ok at this point, with a proper power source as above, connect the + or positive to the PR1's CC2 cables Red wire, and the - or negative to the CC2 cables Black wire. We can connect the PR1 to one of the computers com ports [RS232 port] without or with an proper serial adapter as above, if needed. Make sure the PR1 is fully connected to the port or adapter.
Now all that should be left is to load the software if you have not already done so. The PR1 comes complete with software, but it is always a good idea as with any software to check for new updates. You can always find the latest versions of each software at:
PR1DOS -> http://www.sljkrr.com/
PR1WIN -> http://www.digitoys-systems.com/
These links are direct to the authors sites, John Kabat for PR1DOS and Hans Tanner for PR1WIN. You will always find the most current versions at these sites. And while you are there to get the latest version of either software. It might be a good idea to drop each an email, thanking them for the great work they are doing. A little appreciation never hurts.
Once you have the current version of the software loaded in to the computer, all you should have to do is run the program and you should be all set. Each software should be able to find which port the PR1 is connected to, and the defaults should be all you need to get started using the PR1. If need be you can go into the software's config. sections and make sure it sees the proper comport, and fine tune the software to your system. Read the software's documentation and help screens on how to do this.
But if at this point you can not get the PR1 to work,
we need to do some research and see if we can find out why it is not working
properly. So we read on.
First make sure your programming track and loco wheels are clean as possible. It is very important to make sure the pickup path from track to decoder is conductive as possible. Remember we are working in a pulsed environment, and every pulse counts, that is current limited to protect the decoder, and keep it from running off the track during programming.
If you are going to try and read decoder CV values, make sure there is a suitable load on the decoders motor outputs, see Notes below.
Remember a service mode programmer, such as the PR1,
is current limited to protect the decoder. As such if there is any load across
the programmer output besides the decoder, it can easily load the output to the
point the programmer can not see the decoders ACK pulses. This will usually show
as the programmer can WRITE to the decoder, but can not, or not reliably READ
decoder CV values. Though with enough load it may not even be able to write to
the decoder. Thus it is not a good idea to have more then one decoder on the
programming track at a time. And any loads such a lights, etc that are across
the rails should be disconnected when programming the decoder.
We should also note not all decoders are created equal. Most decoders
depend on the DCC packets from the command station to set the status of
function, On/Off. But some decoders such as NCE for example actually store this
status internally in the decoder. With these type decoders, you need to make
sure you turn off all functions before placing on the programming track, other
wise any loads on these function will also show as a load across the programming
track.
If you have a laptop, make sure there are no PC cards inserted into the PCMCIA slots. Also with a laptop or desktop, if you are using power savers, be sure they are not watching the comports. It is also a good idea with a laptop to make sure it is not on battery power, use your mains adapter here.
With a multitasking OS such as WIN 95 and 98 it is always a good idea to make sure there are no programs running in the background that are hooking to the comports. Pressing CNRL/ALT/DEL will bring up the close program window. Here you can select all the programs that are running in the background and stop them from running. Note here they will resume again as soon as the system is rebooted. Close all tasks except for 'Explorer'. If this gets the PR1 working properly for you, then you can try closing each task one at a time to find the offending one.
Next is we can be having problems with FIFO this simply means First In First Out. What it really is, a buffer and it can introduce a a variable time delay of up to almost 10ms. This delay can simply confuse the software and makes proper readings almost impossible. Or in other words, computer thinks it is at a place in time, and the decoder really is at another. Thus if we are having problems with the PR1, it is a good idea to try it with FIFO Off.
The easy way to turn off FIFO with Win3.x is add the following in the system.ini file: [386Enh section] add COMxFIFO=off, where x=your com port number. This will disable the FIFO buffer on the stated comport.
For Win95/98. Right click My Computer then
properties, then Device Manager, look down the list for Ports [COMM & LPT]
then open and double click on Communications Port [Com x] 'x' is the port number
you are going to use. Then click on on the Port Setting Tab then Advanced,
uncheck 'Use FIFO'.
There is always the possibility that your system is not communicating properly with it's own comports. This will usually be indicated by the Red slash on the PR1WIN PR1 icon. If the computer can not talk to the port, the software can not see the PR1 is connected. But at the same time, please note, even if the PR1 icon and/or the Loco Icon is slashed out, try the PR1 anyways. It is possible for the PR1 for the PR1 to still work. But if not then read on.
A computer can have up to 4 or more com ports. But again today's systems only come with generally 1 external port. So the choice is pretty easy.<g> But we need to make sure that the system has this port properly setup and working. Follow the directions for the OS that you are using to do this.
DOS and Windows 3.x:
We need to run a program called MSD.EXE, this is the Microsoft System
Diagnostics. At the C:\DOS> or C:\Windows> prompt (or subdirectory where
MSD.EXE is stored) type MSD and press <Enter>. MSD will now examine your
system and display a configuration screen. To check the status and addresses of
the COM ports in your system, press the underlined letter 'C'. MSD will display
a screen showing all the port status, such as what is being used, what is N/A,
Port addresses, Baud Rate, Data Bits, Stop Bits, UART type, etc.
At this point just make a note of which com ports have an address assigned to them, these will be the ones available to the system and the same that you can connect the PR1 to.
Windows 95/98:
With Win95/98 this is pretty easy to do, just right click My Computer then
properties, then Device Manager, look down the list for Ports [COMM & LPT]
then open and double click on Communications Port [Com x] 'x' is the port number
you are going to use. The first thing you should see is under Device Status, and
that is 'This Device is Working Properly' if not you have some work to do with
Windows to get it working properly. Once you have the port 'This Device is
Working Properly' now click on the Port
Setting Tab. Pending on the system used and the default settings you should see
something like. Bits per second = 115200, make sure it is at least set to 19,200
or higher. Also the rest should be down the line, 8, None, 1, and either none or
xon/xoff.
You can use each software to help track down where
the problem might be. As example if PR1DOS works properly, but
PR1WIN will not, you can assume you have a problem with your Windows port
settings. If there is a problem with the PR1 or Computer ports, the PR1DOS would
not work either. If neither works, then there is either a problem with both
Windows and DOS port settings, or more then likely it is a case of the computer
ports them self being almost RS232 ports.
This simply means you have tried all the above and the PR1 still will not work at all or properly.
There always is the possible of the PR1 being faulty. You can check this by swapping it with a known good one. Or just asking your dealer for another. The odds against the PR1 being faulty is slim, getting two faulty ones is even slimmer.
If swapping the PR1 out does not do it, then at this point we have boiled everything down to the possible fact that the computer's comports will not support the PR1. Most computers will not have a problem here. But there are some that have on mother board ports that are not quite up to specs for RS232 communications, or as I like to call them, 'Almost RS232 Ports'. This simply means that the PR1 is dependent on port specs of voltage and current, and these ports are not able to supply these requirements. They may well work fine with a powered device such as a modem, or a non-dependent device such as a mouse. And still not work with a PR1 which depends on the port meeting RS232 specs. It is simply that they build the ports on the mother board, they have control of how it will be circuited into the mother board, so they take a few cost cutting short cuts here and there.
So now you have a few choices to make. The best answer here is to buy and install a port card. These Mfg have no idea what their cards will be plugged into so they more or less have to follow the standards to assure compatibility from system to system. And as a result you have a proper port to use with the PR1. I have a system that will not even boot up with a non-powered RS232 device connected to a port. This same system with a SIIG port card works fine with the PR1 or MS100, even a mouse. With a SIIG dual port card I have 4 usable ports. As long as your O/S and Bios will support high IRQ's you can easily get 4 working ports this way. This is how I have my layout computer working. The reason I run all 4 ports are mouse, modem, PR1, and MS100. I do some beta testing and this config will work out any PR1 or MS100 software out there.
The other choice is to build an PR1 alternate, one that does not depend on the RS232 specs. Currently there are two choices here that I know of. they are DIY, or Do It Your Self. The reason they will usually work are they are designed to be separated from the computer port and supplied by their own power source, so they get a bit more complex then the PR1 is. If interested take a look at:
Bob Backway's design at:
http://www.geocities.com/OzDCC/decprog.htm
Or Wayne Roderick design at:
http://www.ida.net/users/tetonsl/railroad/DCCpr1.htm
Both a little different in design, but work to solve the problem of computer almost RS232 ports one uses resistive isolation the other a TTL to RS232 driver. Both require they be powered form an separate power source. And as a result a little more complex then the simple design of the PR1, but are an alternate for those who may need it.
A third alternative is the SPROG
II like it's predecessor SPROG is a computer
based programmer for DCC decoders. Born out of the frustration felt by many
trying to use the PR-1 and inspired by the MERG
standalone programmer, SPROG II is supported on a range of hardware platforms
and operating systems by DecoderPro.
If you have any questions or feel there is something
else to add here, please 
At this time the PR1DOS software works with DOS,
pending the system speed may or may not work in a DOS window. If the system is
to slow, you will need DOS mode, that is exit Windows and reboot to DOS [command
mode]. If the system is fast enough, then simply using a DOS window inside
Windows will work. One of the major differences here is, when used in a
DOS window, the ports are still under the control of Windows so the Windows
settings are still enforced. When you boot to DOS mode, the ports are under
control of DOS settings and they may be different then the Windows settings.
PR1WIN, is
a 16bit application, and will not currently work with Windows NT nor 2000. But
should work with Win 3x/95/98 and some versions of Millennium. There is a beta
version of PR1WIN 32bit version at:
http://www.digitoys-europe.com/betatestprogram.php3
There is a PR1WIN FAQ Page at: http://www.digitoys-systems.com/PR1_FAQ_e.htm
You need a load on the decoders motor outputs to be able to read the programmed CV values. This is simply because the decoder uses the motor output to sink current as the ACK pulse to acknowledge that the programmers value request is a match to that stored in the decoders CV. This load is generally the loco motor the decoder is installed in. But in cases where the decoder is not installed, or used with a non-motor application. Then a suitable load must be placed across the decoders motor output leads, the Orange and Gray wires. A 100 to 120 Ohm 2 Watt resistor will make a suitable load for this application. You can freely remove the resistor after you are done reading decoder values if you like.