Date   : Sun, 12 Jul 2009 21:19:41 +0100
From   : afra@... (Phill Harvey-Smith)
Subject: Atom Questions

Sorry brain dead idiotic list policies strike again !
this was MEANT to go to the list !

Ian Wolstenholme wrote:
 > I've been playing with my Atoms.  They all work but one of them has a
 > faulty 6502 and one of them I can't tune in properly to the TV.
 >
 > Just a few questions have sprung to mind:
 >
 > 1. To upgrade them all to 12K RAM, I need 10 x 2114 RAM chips.  Has
 > anyone got any?

Yep you would need 2114s unless you have an add on ram board.

 > 3. What would happen if I put in a 2MHz (or more) 6502?

Should work fine, I have run one of my machines with a WD65C12, though 
you do have to add a pull-up to pin 36 if you do this, as the WD chip 
needs this pin pulled up, it's not used on the original 6502, so 
shouldn't be a problem with that either.

You could of course use the 6502 out of a BBC or Electron without problems.

 > 5. What is the correct connector for the Acorn expansion bus?  Is it a
 > male or female connector?

Male.

 > 6. How can I find out what optional ROMs are connected to the Atom
 > without taking them out and reading them in an EPROM programmer? Is
 > there an equivalent of *ROMS or *HELP?

Have a look at the Atom memory map and peek the relevant sections.

 > 7. Can I get colour graphics without any extra hardware?  The manual
 > seems to suggest I can, with a special plotting routine or using the 
COLOUR
 > command on the Floating Point ROM.  One of my Atoms has the FP ROM but
 > it's the one I can't tune in properly, so it's possible that it's 
doing colour but I can't see it.  I thought there was a separate colour 
board though.

Nope you need an extra Colour board, the standard Atom will only output 
monochrome video.

Does your TV have composite input ? if so there are 2 pins on the 
expansion video connector that can be used to feed this direct to the 
TV, and bypass the modulator.

Cheers.

Phill.

-- 
Phill Harvey-Smith, Programmer, Hardware hacker, and general eccentric !

"You can twist perceptions, but reality won't budge" -- Rush.