[Search for users] [Overall Top Noters] [List of all Conferences] [Download this site]

Conference 7.286::keyboard_design

Title:New Keyboard Issues
Notice:Relocated to Marlboro
Moderator:HANNAH::SICHEL
Created:Thu Mar 27 1986
Last Modified:Thu Jun 05 1997
Last Successful Update:Fri Jun 06 1997
Number of topics:264
Total number of notes:1339

262.0. "PS/2 and 4 pin modular electrical compatibility?" by MQOOA::LEDOUX (Vincent [email protected]) Tue Mar 25 1997 07:08

    Can a LK411 (PS/2) be modified to have a RJ type
    connector (4 pin modular �la LK401)?
    
    The problem is a fairly long story.
    
    The older model (rev E) had an option that we were
    selling blank keycaps.  One customer of us was selling
    VAX 4000 with these "homemade" keycaps.  Now a design
    problem in the keyboard caused the rev E to be replaced
    by rev J and a new manufacturer.  The "old" LK401 was
    totaly purged from our logistics.  The new keyboard
    does not have the same physical keys and no blank keycap
    option.
    
    The customer can still get "older" LK411 with the same
    old keys, but all of them is PS/2 and will not fit
    on a 4 pin modular.
    
    So my question remains, is the PS/2 and 4 pin modular
    electrical specs the same?  Would a cable replacement
    work?
    
    Thanks,
    
    Vince.
    
T.RTitleUserPersonal
Name
DateLines
262.12970::SCHMIDTSee http://atlant2.zko.dec.com/Tue Mar 25 1997 20:1311
Vince:

  The signalling protocol and power levels are completely
  different. The LK201 series (and the compatible LK401
  keyboards) used 12v power and 4800 bit/second RS232
  signalling. The PC keyboards use 5v power and a custom
  TTL protocol.

  There's no compatibility between these.

                                   Atlant
262.2Nope...XDELTA::HOFFMANSteve, OpenVMS EngineeringWed Mar 26 1997 10:534
   The RJ-series LKs are completely different from the DIN-series LKs: more
   than just the connector and the conductors is involved in the changeover
   between the "DIGITAL classic" and "New DIGITAL" keyboard interfaces.
262.3MQOOA::LEDOUXVincent [email protected]Thu Mar 27 1997 08:488
    Thanks guys,
    
    Really appreciated,
    
    We'll try to find an other solution.
    
    
    Vince.