====== Micro-Manager 1.4 and Filter Wheel ======

This Technical note is to document the known issue when connecting micro-manager(MM) with ASI's filter wheel and work around for it. 

On Startup MicroManager does the following:

  * First MM does is to issue serial command <wrap cmd> VB 6 </wrap> to set the controller in verbose mode 6, where <wrap reply> 0> </wrap> or <wrap reply> 1> </wrap> prompt isn't given.
  * Next it selects the filter wheel being added <wrap cmd> FW0 </wrap> or <wrap cmd> FW1 </wrap>
  * Then queries the firmware version with <wrap cmd> VN </wrap> command.
  * Next sets spin mode to 0 with <wrap cmd> SF0 </wrap> command
  * Then queries the controller for number of filter positions with <wrap cmd> NF </wrap> command
  * Next queries the spin mode again with <wrap cmd> SF </wrap> to make sure spin mode is idle.
  * Then queries the status of the controller with busy command <wrap cmd> ? </wrap>. If the controller replies with <wrap reply> 0 </wrap> indicating controller isn't busy, then MM issues <wrap cmd> MP 0 </wrap> command to move wheel to position 0.
  * Often the reply to <wrap cmd> ? </wrap> isn't as clean as a <wrap reply> 0 </wrap>. Then MM issues <wrap cmd> SF0 </wrap> again , followed by Home <wrap cmd> HO </wrap> command. Then it polls busy <wrap cmd> ? </wrap> command every 20 milliseconds until it gets a <wrap reply> 0 </wrap> as reply. Does it at least a 100 times. If it never gets <wrap reply> 0 </wrap> as a reply, then it gives up gives "Filter wheel doesn't appear to be connected" error# 10030. 
  * Some times Home <wrap cmd> HO </wrap> command causes another error. <wrap cmd> HO </wrap> command replies with an echo <wrap reply> HO </wrap>. Because of legacy this command isn't terminated and a time out is used by MM to wait for the reply to come. If the reply is delayed and the timer runs out and doesn't get the reply for <wrap cmd> HO </wrap> , MM gives a "Unrecognized serial answer from ASI device" error# 10009 instead. 
  * __The fix__, on startup of controller, before connecting to MM, press the NEXT button a couple of times, this clear up any <wrap reply> 11 </wrap> errors. So when MM queries with busy <wrap cmd> ? </wrap> command, it gets the <wrap reply> 0 </wrap> reply right away and it avoids the whole <wrap cmd> HO </wrap> command issue. 




{{tag>fw1000 tech_note}}