Are the first 256 CVs traditionally used considered page 0 or page 1?
I see documentation for some decoders that indicates page 1 for CVs above 256 (like CV 1.257).
When you are editing CV 256 or less (the basic ones referenced in documentation) should you be setting CV32 to 0 or 1?
Is the page ignored when you reference a CV less than 257?
Are you referencing paged mode programming (which isn;t this at all) or the concept of paging as a method of handlign indexec CVs for systems that can set a CV over 255?
The NMRA seems to freely mix up 0 based and 1 based counting. Since there is no CV0, the range has to be 1-255, 256 requires 9 bits to represent. ANd then is 0 skipped every time thereafter as well? IE, from an engineering/programming/how basically every digital computer works, you'd have 0.1-0.255, then 1.0 would be the equivalent of 256. Or do they use 1.1?
All this cobbling on is what happens when the use far exceeds the capabilities of whate exited when the original specifications were designed. Back in the day, there were no sound decoders, and even with a 28 step speed table (possibly a reason why there was no 128 step speed table is because it would use too many CVs) and multiple effects across 4 or 6 function outputs, it was nowhere near using 255 CVs. 255 CVs should be enough for anyone (just like 640K RAM should be enough for any computer, now a $2 microcontroller chip has more.)
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
Thanks Randy. I am talking about indexed CVs. I understand Paged Index CVs are for 257-511 (so 1-256 and 512-1024 are normal CVs).
Can I assume that when you read/write to CVs 1-256 or 512-1024 that the value of CV 31 and 32 doesn't matter? And that the page index is only relevent when you are working with CVs 257-511?
Index CV's don't matter for 1-255. CV 256 is MIA for reasons that Randy explained.
They do for 257-512. I don't know what happens with CV's above 512, I understand they are for accessory decoders.
I've never seen CV's discussed here in terms of being on Page 0 or 1 nor the need to know that bit of data. Where are you getting that information?
Henry
COB Potomac & Northern
Shenandoah Valley