LCDInfo.com
http://forum.lcdinfo.com/

Question about 128X32-311 BUSY line
http://forum.lcdinfo.com/viewtopic.php?f=6&t=1473		 Page 1 of 1
Author:  beelzerob [ Mon Jan 30, 2006 22:06 ]
Post subject:  Question about 128X32-311 BUSY line
My Noritake 128X32-311 is on it's way....seems to be the perfect "starter" VFD. Thanks for the schematics posted in the forum, and I look forward to making it show stuff via LCDInfo.

The schematic shows the BUSY line as not connected. The spec sheets I've seen for this display, though, indicates that in order to have the fastest response time on the VFD (especially in flickerless mode), the BUSY line should be polled. I'm just curious why this isn't being done. Is polling that line over the parallel port not practical? Or does it not actually benefit you to do so? I know display update rate is one of the main criticisms of this display, and I would think polling the BUSY line would ensure the fastest rate.

Thanks for any illumination. :)

Oh, and for anyone who has wired this (which I'm in the process of doing)...Should I connect EVERY GND signal together? Whether logic pins or the GND wire from the molex connector...crimp them all together? Thanks!
Author:  coorz [ Mon Jan 30, 2006 22:20 ]
Post subject: 
Well the BUSY issue you'll have to ask Henri or Eelco (LiqUId-MP3) but i'm quite sure if they didn't implement it, they'd have good reason!
No need to hook up all ground pins (should, but i never do that).
Author:  beelzerob [ Mon Jan 30, 2006 23:21 ]
Post subject: 
coorz wrote:
Well the BUSY issue you'll have to ask Henri or Eelco (LiqUId-MP3) but i'm quite sure if they didn't implement it, they'd have good reason!
No need to hook up all ground pins (should, but i never do that).


Ok...hopefully Henri will pop in with an answer here, and I'll email Eelco about it. I'll plan to hook up all the grounds, just since it won't be hard to do.

You know, I swear...lcdstudio, lcdinfo and liquid mp3 should just MERGE. :wink: But that's my own personal opinion....

EDIT: Ummm...I couldn't find a user named Eelco at liquidmp3. :?
Author:  coorz [ Tue Jan 31, 2006 1:02 ]
Post subject: 
Eelco=Schijf :wink:
Author:  beelzerob [ Tue Jan 31, 2006 1:06 ]
Post subject: 
oh, ok. gotcha
Author:  Zee [ Tue Jan 31, 2006 1:36 ]
Post subject: 
On my Noritake 256x64 VFD there's no dedicated busy-line but the controller is faster than the LPT port in my PC so I don't have to worry about it.
Author:  beelzerob [ Tue Jan 31, 2006 2:10 ]
Post subject: 
Zee wrote:
On my Noritake 256x64 VFD there's no dedicated busy-line but the controller is faster than the LPT port in my PC so I don't have to worry about it.


Must be nice. :wink:

Well, Spock over at lcdstudio.com gave me some insight. I think it boils down to the idea that polling inputs is bad....it's basically a great way to eat up CPU. I'm guessing that's why wiring diagrams don't even bother with it. Why would I want to dedicate my entire PC to running this VFD? :lol:

I suppose in theory the BUSY line could be incorporated into the IRQ....but I think I've just exceeded what I feel I can do for my first VFD adventure.

Oh well, worth a try.
Author:  Henri [ Mon Feb 06, 2006 14:12 ]
Post subject: 
If I remember correctly polling the BUSY line was tested with this display but it was even slower that way. A lot slower.
Anyway polling in windows isn't really useful anyway because of the reasons mentioned.
Page 1 of 1 All times are UTC + 2 hours
Powered by phpBB® Forum Software © phpBB Group
http://www.phpbb.com/