QUESTION: Why can't I use the MyIDE-XE Internal Interface in my 800XL?
          Is there a way to "work around" This?
 
KEN WRITES:
Regarding the 800xl: If you take the top case cover, keyboard, and rf shield off 
of an 800xl, and look at the CPU, its the second 40-pin chip from the right, all 
the way in the front of the machine. If you notice, the case is only about 1.25" 
thick in this area. The keyboard is backed by a steel plate and set at an angle, 
considerably lower than the top of the case. If you put a lump of modeling clay 
on top of the CPU, and assemble the case, and then take it back apart, you will 
notice that even with the RF shield left out, it smashes the clay to about 3/16 
of an inch. This is the amount of clearance available above the CPU socket in an 
800xl. There is no way to mount an interface board there.
 
So if you have an 800XL, be sure and order the new MyIDE-800XL Internal 
Interface. It plugs into the OS ROM socket in the 800XL, which is all the way in 
the back of the machine, where there is plenty of clearance. 
 
 
QUESTION: Why can't I use the MyIDE-XE Internal Interface with my 1200XL?
          Is there a way to "work around" this?
 
KEN WRITES:
Regarding the 1200XL: This is a really cool machine, and has plenty of room for 
the MyIDE-XE board above its CPU location. It also has 100% socketed chips from 
the factory. What it does NOT have is a 16k OS ROM. There are 2 ways to get 
around this:
 
Option A) split the OS ROM image into two parts and burn them to two 8k (2764) 
EPROMS, and change the motherboard jumpers accordingly. Once you have these 
special ROMS installed, the MyIDE-XE will work fine.
 
Option B) The 1200XL actually HAS facilties on the motherboard (extra holes) to 
mount the larger (28pin) 16K ROM SOCKETS. If you are willing to desolder and 
replace the ROM sockets and replace your 1200XL MMU chip with an 800XL MMU chip, 
You can simply "drop in" the standard 16k 28pin (27128) EPROM that is used for 
the MyIDE OS image in the 800xl or 130xe.
 
 
The following is taken from an article by Bob Woolley, describing this 
modification:
 
First thing you may find is that the
1200XL ROMs are 24 pin devices and the new ROM is a 28 pin package. No
problem. All of the 1200XL main boards have 28 pin sites for the ROMs.
All you need to do is pull the 24 pin socket at U13 and solder in a 28
pin unit. One more address line (A13) is needed, so remove the W6 jumper
and solder a wire from pin 23 of the CPU chip (U21) to the top pad of W6.
Now, plug the 800XL OS ROM into U13. The 16K ROM select is just as
simple. Take a look inside your 1200XL. See the chip that has 20 pins
(U14)? That is your MMU. It is the main difference between a 1200XL and
an 800XL. Same number of little pins, same number of inputs and outputs
.....? But the 800XL IC has the 16K select for the OS ROM. So, lets jump
right in and swap the MMU with the 800XL part (CO61618). Fits just fine,
doesn't it?? Pull out all the jumpers except W11, W12 and W9 and you have
a ROM select line that will select the address range from $C000 to $FFFF
in a single ROM, like the 800XL.
 
QUESTION: Which Interface board should I order for my XE Game System?
 
KEN WRITES:
The XEGS has PLENTY of room inside it. Both Internal Interface kits work fine 
with it. The MyIDE-XE board plugs into the CPU socket and requires one 
additional wire connection to pin 14 of the 74LS138 IC on the motherbaord. The 
MyIDE-800XL plugs into the OS ROM socket and requires 3 wires: 1 to pin 14 of 
the 74LS138, and 2 wires to pins 36 and 39 of the CPU.
 
Regardless of which kit you decide to use, be sure and specify that it's going 
into an XEGS if you order the Boot ROM. The XEGS Boot ROM is a 32k ROM instead 
of the 16k ROM used in the other XE and XL series computers. 
 
 
QUESTION: Why did you originally design the internal interface board for the XE 
          machines rather than the XL? Is there an advantage to the XE 
          architecture over the 800XL or 1200XL? 
 
KEN WRITES:
 
First of all, I have recently designed a new MyIDE-800XL board specifically for 
the 800XL. It is now available from Mr.ATARI.
 
The MyIDE-XE Interface board was desiged to make the cleanest possible 
installation in a 65xe, 130xe, or 800xe machine with the fewest possible solder 
connections. The 130xe uses the same 16k OS ROM as the 800xl, and has plenty of 
room above the CPU location on the motherboard for the interface board to 
reside.
 
Regarding the 130xe: This really is the ultimate evolution of ATARI 8-bit 
machines. The 130xe has the ability for the ANTIC chip to adress banks of 
extended RAM independantly of the CPU. In otherwords, you can be manipulating 
one bank of RAM with the CPU, and having ANTIC look at a different bank of 
extended RAM for its display list and/or bitmap data. This is an AWESOME feature 
from a coding standpoint and makes a huge difference when you are trying to make 
the machine do serious graphics applications, and are running into resource 
limits. This is called ANTIC EXTENDED VIDEO mode, and you cannot upgrade an 
800xl to do it, without adding several extra chips from a 130xe(in addition to 
those required for a memory upgrade), which noone offers an easy upgrade to do. 
The downside, in many peoples' oppinions, is that the XE series (manufactured 
later, in the years when Jack Tramiel had aquired ATARI and was "cost cutting" 
the whole operation) was made rather cheaply. The factory RAM chips are slow, 
often mismatched, and error-prone. The motherboards, while of equal quality to 
most previous ATARI boards, are notorious for MANY cold solder joints and bad 
conections. This problem is further compounded by the fact that the vast 
majority of XE machines had all chips and ICs soldered in, rather than socketed. 
Also, the keyboards often have a very "mushy" and cheap feel to them. 
 
When I get a 130xe, the first thing I do is desolder every single chip and IC on 
the board. I throw away all of the RAM. I then install sockets for every single 
chip and IC, replace all the electrolytic capictors (theres only about 6 of 
them), replace the RAM with 120ns or faster, resolder every single joint on the 
board, and install the "ST FEEL" replacement spring kit in the keyboard. After 
doing all this, the 130XE is truly the best of the 8-bit line in every way, in 
my opinion. 
 
 
QUESTION: Do I absolutely NEED the 2.5" notebook drive adaptor shown in the
          MyIDE-XE Installation guide?
 
KEN WRITES:
Regarding the 2.5" notebook drive adaptor: You only need this if the drive 
you plan to use is a NOTEBOOK hardrive. They use a smaller row of header pins 
(.060" spacing vs .100" spacing on the desktop drive) for the IDE bus 
connection.

This header also includes 4 extra pins on the notebook drive because power and 
ground is fed through them, rather than through a separate 4 pin connector as is 
the case with a desktop drive.? The adaptor is cheap and commonly available for 
a few dollars from most computer parts vendors. 
 
If you decide not to use the notebook adaptor, you will have to use a DESKTOP 
drive. But you will have several problems with this: a) you wont fit it inside a 
130xe or 800xl without massively modifying the casework. b) you will BURN OUT 
your ATARI power supply if you try to power a desktop drive off of it. c) even 
if you mount the drive externally and power it separately, you've still got the 
problem of getting the bus-cable out of the case in some fashion that looks 
halfway decent.
 
Notebook drives are small, quiet, and draw less than .5 amps of current at 5 
volts. Desktop drives require both 12 volt and 5 volt power inputs, and draw 
anywhere from 1.2 amps, on up depending on the model and generation of drive 
technology.? The best atari power supplies are only 1.5 amps, and not designed 
to handle this additional load.
 
 
QUESTION: I have heard that some people are using CF cards instead of hard
          drives. What is this all about?

KEN WRITES:
The third option (not shown in the XE installation guide) is to get another type 
of adaptor: A CF (compact flash media) to IDE adaptor. This adaptor is about the 
same size as the notebook adaptor and is also commonly available. This allows 
you to use a CF card instead of a drive. CF cards (used in many digital cameras 
and other portable devices) are very small and have almost negligable power 
requirements. They are also based on solid-state non-volatile flash memory and 
are not prone to the mechanical failures and heat related issues commonly 
associated with the eventual failure of hardisks. CF cards can be found in 
storage sizes ranging from 8mb to 1gb.
 
 
QUESTION: I am having trouble deciding on which drive or CF card to use. 
          How much storage do I actually need?
 
KEN WRITES:
When selecting a drive or CF card keep this in mind: anything larger than about 
500megs in my oppinion, is somewhat of a waste.? The most you can do is have 8 
16meg partitions of Mydos or Spartados. Ok Thats 128megs. The rest of the drive 
is left over for bootable disk images. Every piece of commercal software EVER 
RELEASED for the 8-bit atari (games, applications, everything) fits in less than 
200megs. Mr. Atari has done some work on streaming video data directly from the 
hardisk, and this is one possible application for all the extra space, but if 
what you want is a hardisk system to use in the traditional manner associated 
with filesystem based I/O, 512megs is a good practical size, and often Ive found 
notebook drives of less than 1gb for sale very CHEAP from surplus vendors.
 
QUESTION: What are the benefits and/or disadvantages of the TRANSCEND(tm)
          direct-IDE flash modules?
 
KEN WRITES:
From what I have seen, these things are great. They are a "one-shot" solution to 
internal storage media mounting/power isues where the 8-bit ATARI and MyIDE are 
concerned. If you buy one, be sure to get the version that plugs into the 
standard desktop type IDE connector (.100" pin spacing, 40 pin.) The only issue 
with the thing at all, is that it requires power at pin 20 of the IDE connector. 
All new MyIDE-XE and MyIDE-800XL kits being sold now have a jumper(J2) to enable 
+5v power at pin 20. I did this specifically for compatability with the 
TRANSCEND module (and other devices that may require +5v at pin 20.) If you have 
an older MyIDE-XE (purchased prior to 6/06,) You can solder a wire on the 
underside of the MyIDE-XE board from pin 20 of the 74LS245 to pin 20 of the IDE 
header. Or you could go from pin 8 of the CPU to pin 20 of the IDE header. 
Either way, you are supplying +5v to pin 20 of the IDE header. DON'T DO THIS 
UNLESS YOU ARE SURE YOU UNDERSTAND THE PIN-OUT OF THE DEVICES ON THE BOARD. IF 
YOU FRY SOMETHING, IT ISN'T MY FAULT! 
 
The other issue is that to plug a TRANSCEND directly into the MyIDE-XE, the 
TRANSCEND would stick straight up, creating case-clearance problems. In order to 
accomidate this, I have started using Right-angled IDE headers on all new 
MyIDE-XE and MyIDE-800XL boards. This allows the TRANSCEND to lay flat, and 
everything works fine. 
 
If you have an older MyIDE-XE (purchased prior to 6/06,) you can get an IDE 
extender cable. This is an IDE cable that has a male conector on one end, and a 
female connector on the other end. These cables can be found in the parts & 
accessories section of most computer parts retailers. Get the shortest one you 
can. Plug the female end of the cable into the MyIDE-XE, and the male end into 
the TRANSCEND module, and then you can mount (or simply lay) the TRANSCEND 
module wherever you have room for it in the case.