Sign in to follow this  
Guest kenamt

IOCARD - Stepper Motor

Recommended Posts

Hello AllIam planning on changing from FSBUS to IOCARD and have a few questions to all out there that use IOCARD. 1. How is the refresh speed? This is why Iam changing since FSBUS updates to slow to drive motors for gauges.2. I am planning on stepper motor to drive engine gauges. Is there a home sensor needed to drive the gauges to at start-up?3. The .dat files to show how to config the software does not show a stepper motor. Does anyone have one running to show that?4. I am planning on using stepper motors since it uses only 4 outputs and servo will take 8 outputs. How smooth is the stepper driving? Is the rotation smooth or jumpie?Thanks to all and look forward to hear from other IOCARD builders.Ken Trager

Share this post


Link to post
Share on other sites
Help AVSIM continue to serve you!
Please donate today!

>Hello All>>Iam planning on changing from FSBUS to IOCARD and have a few>questions to all out there that use IOCARD. >>1. How is the refresh speed? This is why Iam changing since>FSBUS updates to slow to drive motors for gauges.By the way, in FSBUS the update frequency for things is defined in the fsif.ini - you can make stuff faster by changing the value after copying the line to "myfsif.ini" and changing the ID field to something starting from 1 and growing them in sequence like on the fsif.ini, just 1,2,3,...n.Many things have a default polling value that is quite slow, like flap indicator, just make the polling value small.//Tuomas

Share this post


Link to post
Share on other sites

IOcard poolling is user defined.USB IOCard use a default time for poolling of 0.75msYou have a example of Flaps indicator using servo-motor in www.opencockpits.comYou need 8 outputs for servo-controller with a resolution of 1-254 values.

Share this post


Link to post
Share on other sites

The USB interface is faster then FSBUS. IOCARD drive stepper motor and I never did get the servo to work with FSBUS.I am still planning on using stepper motors for my King Air engine gauges. I will try to update my refresh speed in FSBUS but since I have the cards for IO system I am going to try that too.The big question is still unanswered - - - - - Will I have to use a home sensor with the stepper motors.Thanks all

Share this post


Link to post
Share on other sites

Hi,first of all, i have no problem with the fact that you want to change. That's up to you.I would like to clearify the often discussed speed.Yes, USB is faster. But this is not the bottleneck. The interval of polling flightsim for values is the critical thing.The best solution would be, if microsoft builds in an event driven system. This would get best response time by minimum cpu action.When polling, fsbus could do it permanent, which gets really great speed, but the required cpu time gets lost for fs. Lower frame rates etc. My design goal is:Make the polling interval as long as possible. Therefor the interval parameter can be defined by each parameter individual. When turning rotaries, a very fast response is required for displays. I send the turns directly to display to update directly and in parallel, i send it to fs. The next polling will get the real fs value and that will probably update the display to the real fs value.During the phase of building my cockpit, i will test the optimal intervals by myself and that will be a compromise.The current problem with the servo is its fast move. I made a new software parameter into the new stepper controller, which defines the speed of movement which results in smooth needle movements, even in long intervals. Maybe i will add this functionality to servo controller. (Later)regards

Share this post


Link to post
Share on other sites

>USB IOCard use a default time for poolling of 0.75msThe PIC16C745 is a low-speed USB chip and the top transfer rate is 8 bytes @ 10ms. Are you sure it's not 75ms instead of 0.75ms? -Leo

Share this post


Link to post
Share on other sites

>The current problem with the servo is its fast move. I made a>new software parameter into the new stepper controller, which>defines the speed of movement which results in smooth needle>movements, even in long intervals. >Maybe i will add this functionality to servo controller.>(Later)Yes, this would be a good idea. We currently had to increase the servo read interval, so that the flap indicator we built does a bit smoother movement. If it just had a "slow pace" set from FSBUS, all it would need is one value - the destination - and it would move smoothly with a defined speed that would be possible to match the speed of the flap extension, thus no extra work for the CPU, just let FSBUS handle it on the PICs.I agree your approach has a good thought in it. You can make FSBUS "fast" too - just crank the "fs read interval" in the preferences. It does faster stuff then - but also eats your CPU.//Tuomas

Share this post


Link to post
Share on other sites

>>USB IOCard use a default time for poolling of 0.75ms>>The PIC16C745 is a low-speed USB chip and the top transfer>rate is 8 bytes @ 10ms. Are you sure it's not 75ms instead of>0.75ms? No.Time for polling is different. Polling is 0.75ms. But if any changes, i send buffer of changes directley to computer.Critical time is for receive changes, not for receive information.

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
Sign in to follow this