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MRC Prodigy Express

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MRC Prodigy Express
Posted by mdtell on Tuesday, August 25, 2009 10:18 PM

I just purchased an MRC Prodigy Express.  I note that I can only imput data into a cv in whole numbers; no decimals.  Some decoder cv's require imput with decimals.  Is there a way to do that with the Prodigy (eg. convert the decimals to whole numbers) and if so, how?

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Posted by mdtell on Wednesday, August 26, 2009 12:32 AM

Thanks.

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Posted by tstage on Wednesday, August 26, 2009 7:59 AM

mdtell,

As David pointed out, it sounds like what you are referring to is indexing.  When you see a "decimaled" CV, here's what the numbers are telling you: Ex. 56.4.30

  • 56 - The CV number you are altering
  • 4 - The primary index (CV49)
  • 30 - The secondary index (CV50)

Simply put: In order to change CV56 in programming mode, you must FIRST change CV49 to 4 then CV50 to 30.  Once you've done that you can then change CV56 to the value it needs to be in order to get the "effect" you're trying to achieve.

mdtell, I would encourage you to download and print out the current QSI manual (V4.4?) and place it in a 3-ring binder.  I find it much easier to peruse through this way and the margins are handy and wide enough for any notes you might want to jot down.

Hope that helps...

Tom

https://tstage9.wixsite.com/nyc-modeling

Time...It marches on...without ever turning around to see if anyone is even keeping in step.

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Posted by mdtell on Wednesday, August 26, 2009 10:21 AM

Tom, thanks.  Can you tell me how to change bit values for any given cv?

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Posted by jalajoie on Wednesday, August 26, 2009 10:48 AM

This is basic binary math and decimal conversion.

A byte has 8 bits numbered 7 - 6 - 5 - 4 - 3 - 2 - 1 - 0 from left to right.

Each bit has a decimal value of 128 - 64 - 32 - 16 - 8 - 4 - 2 - 1 also from left to right

I you want to turn a bit On you program that bit decimal value in the CV. If you want more than one bit On you add each individuals bits decimal values.

Example you want bit 0 and 1 to be On, you then program a value of 3 in the CV (Bit 0 has a value of 1 and bit one has a value of 2 then 2+1 = 3). If you also want bit 7 to be On then add 128 to the equation. Therefore 128+2+1=131 decimal or 10000011 in binary.

This is a very simplistic explanation I guess someone else more at ease with the English language will further clarify the matter.

Jack W.

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Posted by tstage on Wednesday, August 26, 2009 12:45 PM

mdtell
Tom, thanks.  Can you tell me how to change bit values for any given cv?

mdtell,

I think that's where you'll find that the QSI manual comes in quite handy.  The various "bit" settings are listed out for you to see and choose from.  Once you change the primary and secondary indexes, whatever value you enter for the main CV (value = numerical equivalent of the binary number, as described by Jack's post above) will determine what feature you end up employing.

Tom

https://tstage9.wixsite.com/nyc-modeling

Time...It marches on...without ever turning around to see if anyone is even keeping in step.

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Posted by mdtell on Wednesday, August 26, 2009 6:18 PM

Thanks Tom and Jack.  I think I am now on my way to understanding how the programming process works.

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