All I can say is that is not normal so something is not right with your setup. Could be some software you have installed on all computers or could be the three computers are all similar makes?
The driver test should run first time every time and you should not get a difference in its results from first to second test.

Hood

My point is that the driver test is not acurate enough to make decissions with just for reference. If it drives the machine its working.
What is pulsing to fast supposed to mean? Is the computer to fast for the machine? That would be hard to believe since smoothstepper puts out 4MHZ and this driver only puts out at best 100khz.

Steve

My "Pulsing too Fast" was not really a pulsing too fast, that is just where it was when it would crash. It would just work for a couple seconds then stop and this usually left it displaying "pusing too fast", when in fact it was not pulsing at all anymore and died. Even if you fired up Mach3, it woud power up the machine for a second or two then go off, just like the drivertest was doing. I tried everything to make it work and it just did not work. I had no choice but to get a smoothstepper

Machinehead57
The driver test as you say is not a sure thing however I have yet to see a computer that has a perfect flat line not running Mach nicely.
The grey area is where you have some disturbances on the line, it may or may not run nicely. If the line is just a mess then it is almost certain it wont work nice.
Having the driver  test give you pulsing too fast errors then its safe to say you are going to have problems even if you do manage to get some sort of motion.

Regarding what the pulsing too fast means, you would really need to ask Art but my guess would be that it is unstable and thus the driver test sees a pulse there but has no idea what it actually is.
It will definitely run nowhere near the SS, Art has had it running faster than 100KHz if I recall but it was not stable enough for release.

The parallel port driver has its place, if you have a stepper based system and you get a nice clean line in the driver test then you will likely see no benefits from the Smoothstepper, if however you run servos with relatively high count encoders then I would say the SmoothStepper or one of the other external devices is a must.

Hood

Hood I have no problem with Mach I run 10 and 15 amp servos with 1000ppr encoders. I can leave a cut on any axis and come back to it with no real lap line on any of the axis so I know the machine and software is working good.
But I still have to launch the driver test 2 times to get a reading on it. When I do get a reading I keep a clean line up to the 100khz level. But with 4 axis it it slows everything down because there just isn't enough bandwidth in my computer and the parallel port to run it at that speed. It just doesn't display anything the first time up. At this time it really doesn't matter I'm just warning others that the driver test isn't good enough to make major decisions on to get other info to back it up.

Steve

If you get pulsing too fast and have to always run the driver test a second time to get a reading then that is indicative of issues with your computer, I would suggest you try some of the optimisation steps detailed on the downloads page.
Hood

dear Hood, I cannot locate this Win 7 optimisation/optimization in the download area of (Newfangled Solutions) Machsupport .. can I have the link please? maybe others have same problem!

this is it, its for xp but should be relevant to other OS's
ftp://machsupport.com/Extra%20Information/XP%20Optimization%20Guide.txt

Hood