Date   : Sat, 08 Mar 2008 16:23:24 +0100 (GMT)
From   : johan@... (Johan Heuseveldt)
Subject: TUBE chip, accessing 'Parasite' side

Hi,


Sorry, I forget about 'Q'...

On Sat 08 Mar, Johan Heuseveldt wrote:
> On Sat 08 Mar, Jonathan Graham Harston wrote:
> > > Message-ID: <Marcel-1.53-0304133311-b49xSBG@...>
> > Johan Heuseveldt wrote:

> > > (I do use BS to switch RAM for vector access)
> >  
> > I only have a 6809 programming sheet, I don't know what the
> > hardware signals do (other than the ususal ones - NMI, R/W, etc.)
> > What does BS, BA, Q, BREQ do?

[DMA/BREQ, BA, BS, but forget Q]

Q is 1/4 of an E cycle in advance on E. That is, in the middle of the first
half of E - being low - there is the rising edge of Q.

When Q rises, address lines are stable. It is also handy for generating CAS
and RAS signals for dynamic RAM, as I've seen so far.


Greetings,
Johan

-- 
Johan Heuseveldt <johan@...              >
  aka  waarland

  The best place is a Riscy place
 
The Mona Lisa was framed.