Highly Liquid Forum facebook twitter google plus rss feed
  #1  
Old 05-26-2015, 02:25 PM
kosopet kosopet is offline
Junior Member
 
Join Date: Apr 2015
Posts: 18
Default Yamaha cs70m umr2

I am trying to decide is it possible or not to make umr2 adaptation for yamaha cs70m synthesizer. It has also matrix keyboard, but according to its service instructions i am not shure that it is just common matrix keyboard engine with select and data lines. I include schematics of its keyboard matrix and info about keyboard scanning realization from service manual. I need advice about possible or not to make umr2 adaptation for cs70m. When i try to look with scope to select lines, i cant see any solid signals, i can see only some tiny impulses.
Attached Images
 
Attached Images
File Type: pdf Yamaha CS-70M Servicing Guide 2 of 2 ( 11 x 17 - Double Sided ).PDF (234.7 KB, 502 views)
Reply With Quote
  #2  
Old 06-04-2015, 09:45 PM
John's Avatar
John John is offline
Moderator
 
Join Date: Jan 2009
Posts: 3,007
Default

Hi Kosopet,

This looks similar to the switch matrix on the CS40m in your other thread.

Active-high select on KB0..KB09, and data on N1..N7. I'm not quite sure what the voltage levels are, however.
Reply With Quote
  #3  
Old 06-06-2015, 03:06 PM
kosopet kosopet is offline
Junior Member
 
Join Date: Apr 2015
Posts: 18
Default

In the attached pdf there is short description of keyboard scanning circuitry. Is that info consistent with common keyboard matrix engine, desribed on this forum?
Reply With Quote
  #4  
Old 06-06-2015, 04:49 PM
John's Avatar
John John is offline
Moderator
 
Join Date: Jan 2009
Posts: 3,007
Default

Quote:
Originally Posted by kosopet View Post
In the attached pdf there is short description of keyboard scanning circuitry. Is that info consistent with common keyboard matrix engine, desribed on this forum?
Yes, it is a typical keyboard switch matrix.

The part that might be confusing are the buffer ICs on both sides (select and data).

Assuming the voltage levels are acceptable, the UMR2 would be connected directly to the switch matrix as usual.
Reply With Quote
  #5  
Old 06-07-2015, 10:15 AM
kosopet kosopet is offline
Junior Member
 
Join Date: Apr 2015
Posts: 18
Default

Ok, the only thing which worry me is that the scope picture looks very differend from cs40m. I'll make scope photos of select and data lines soon.
Reply With Quote
Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT. The time now is 10:31 PM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2017, vBulletin Solutions, Inc.