tonja jorenby

BUS_PORT aka the memory mapped $B5xx addresses W/ CS'

Discussion created by tonja jorenby on Feb 23, 2006
Latest reply on Feb 24, 2006 by Jim Willette
 I would like to use this external device expansion BUS_PORT as it is called in the various manuals that I have for the MC68HC11.  The problem is, I can't find any hard data on how to do so!  My most pressing question is, do I need to set the direction of the data pins (D0-7) everytime before I write to my address block, and if so, how/where?
 Do I need to use the R/W pin that's on that bus? (if so, how?)  And, if I write all my addresses for my external device to the same CS' address block, is the CS' going to pulse every time I change address?  Anybody found an AppNote on this, because I sure didn't and it wasn't for lack of trying.....TJ