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RAM Upgrade Options

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I finally took the top off the case of my 65XE and it's one of models which was essentially a 130XE without the second 64K of RAM. That was added later (some time in the early nineties).

 

post-21964-1233255381_thumb.jpg

 

There appear to be a couple of extra wires, etc, soldered in as well. I can't remember the specifics at all. I notice the second 64K of RAM is seated in IC sockets. Surely that's a good thing (to save me doing risky soldering). What's the easiest upgrade in this instance (to, say, 256K or 320K)?

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easiest one if you have already another 64k installed would be pull out those 1x64kbit devices and put there 1x256kbit ones

this would give you 320kb of ram total - should be enought

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easiest one if you have already another 64k installed would be pull out those 1x64kbit devices and put there 1x256kbit ones

this would give you 320kb of ram total - should be enought

Does anything else have to be done to give 320K?

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let me think

yyes, you need to add multiplexer to some pio portb lines, and connect its outpu to additional adress line of 1x256kbit chips

74ls157 if i recall correctly

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easiest one if you have already another 64k installed would be pull out those 1x64kbit devices and put there 1x256kbit ones

this would give you 320kb of ram total - should be enought

This sounds ideal; minimal soldering and a couple of extra parts. Is this a "recognized" upgrade method for which I could find full instructions?

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The 65XE 130XE/320K Upgrade!

 

by Scott Peterson

 

I have written the following documentation in such a manner that you can

use it to help you keep track of your progress as you assemble this memory

enhancement. Simply place a check in the space provided as you proceed. This

will allow you to readily follow your progress, and pick back up where you

left off if you should have to stop.

 

Once you have finished this upgrade you will then have in your possession an

Atari 65XE with 320K of total ram. This is broken down into chunks of 64K of

standard ram, and 265K of page mapped ram. This upgrade is 100% compatible

with the previous 130XE/320K upgrade and therefore will run all programs that

the earlier enhancement ran.

 

Disclaimer:

 

The Author nor this BBS claim any responsibility for any type of damages

incurred by do this modification

 

The equipment you will need is:

 

A: A medium sized Phillips head screwdriver.

 

B: A very small jeweler's screwdriver with flat blade.

 

C: Soldering wick (recommend Chem-Wik .100 inch size), or vacuum desoldering

pump.

 

D: Soldering station (like Weller model WTCP), or LOW wattage soldering

pencil of the 15-25 watt variety.

 

E: Small pair of needle-nosed pliers.

 

F: #30 gauge wire (Jameco #130 BE)

 

G: Wire stripping tool for #30 gauge wire ("Clip and Strip" Jameco #CAS-130).

 

H: Heat shrink tubing or black electrical tape (tubing preferred).

 

I. Small pair of wire snippers.

 

J: Optional: Small carpet sample or blanket.

 

The parts you will need are:

 

A: Z1-------> 74LS158

 

B: Z2-------> CO25953 (Custom chip by Atari)

 

C: Z3-Z10---> 256K Ram chips #41256-150 (8 required)

 

D: R1,R2----> 33 ohm 1/4 watt resistors (2 required)

 

And here we go.................

 

1.___Place carpet sample or small blanket on a clean, uncluttered workspace

that is well lighted.

 

2.___Situate all tools and parts on one side of your workspace.

 

3.___OPTIONAL: Get a fresh cup of coffee!

 

4.___Place 65XE face down on carpet. Remove all screws holding cabinet

together. Turn unit over. Remove top of cabinet and lay it in a safe place.

 

5.___Gently pull upward with fingertips on mylar extending from keyboard and

remove it from its connector. Place this keyboard assembly with the top of

the cabinet. Place screws in a small container so they won't be misplaced.

 

6.___Take needle-nosed pliers and turn all twist tabs on metal shield so it

may be easily removed. Remove all screws from outer edges of PC Board and

then place screws in your container, and the top and bottom shields along

with the bottom of the cabinet should be placed with the rest of the 65xe

cabinet.

 

7.___Place all ICs in front of you and proceed with the following:

 

a.___Bend up pin number 15 on all 8 of the 41256 rams. Then snip off the thin

part of the leg so all you have left of pin 15 is the "stub" or fat portion.

Do this on all 8 rams.

 

b.___Bend up all pins with the exception of 8 and 16 on the 74LS158. Leave

the legs on 8 and 16 long, and snip the thin part off all other pins on this

chip.

 

c.___Bend up all pins with the exception of 8 and 16 on the CO25953. Leave

the legs on 8 and 16 long, and snip the thin part off all other pins on this

chip.

 

d.___Take both 33 ohm resistors and snip the leads so their is 1/4 of an inch

of lead left on either end of each of these resistors.

 

e.___Place these chips to one side, and position the 65XE motherboard in

front of you. Locate IC numbers U9 through U16. You will find them running

along the left side of the motherboard. Take a piece of tape or a small black

magic marker and place a small mark next to the IC that is labeled U12. You

see the wisdom of doing so later on in this documentation.

 

8.___Proceed to piggy-back ICs Z3 thru Z10 inclusive on top of ICs U8 thru

U15 inclusive. Please take your time and be sure that each chip is facing

the same direction as the integrated circuit below it. Do a good job

soldering so not only will this upgrade work well but also will be pleasing

to the eyes when you show it off to your admiring friends!

 

9.___Cut 7 small pieces of #30 gauge wire, and use these to connect all 8 of

the pin 15s of the piggy-backed rams.

 

10.___Gently turn the 65Xe motherboard over exposing the underside to your

trusty soldering iron. Cut 7 more small pieces of #30 gauge wire and then

proceed to jumper all the pin 1s of the rams. Cut another piece of #30 gauge

wire approximately one foot long and solder it to pin one also and then run

it through a convenient hole in the motherboard. Turn the motherboard back

up with parts side once again smiling up at you.

 

11.___Grasp the 74LS158 and proceed to piggy-back it on top of an IC on the

motherboard labeled U24 which you will find at the front right of your

computer. Make sure it is facing the same direction as the chip you are

placing it on top of and proceed to solder pin 1 of the 74LS158 to pin one

of U24. Next solder pin 16 of the 74LS158 to pin 16 of U24.

 

12.___Grasp the CO25953 IC and proceed to piggy-back this gem on top of U2.

U2 can be found approximately in the dead center of your 65XE motherboard.

Again, please make sure both chips are facing the same direction. Remember,

a slow, sure job is often-time the fastest job overall! Proceed the solder

pin 1 of the CO25953 to pin 1 of U2. Next, solder pin 16 of CO25953 to pin

16 of U2.

 

13.___Grasp one of those 33 ohm resistors you have previously trimmed and

solder one end to pin 15 of Z3. Z3 you ask? Why that is the chip which has

been piggy-backed on top of U12. U12---you know that one! that's the chip

we so wisely marked before we started!

 

14.___Cut a short piece of wire and attach it to the free end of the resistor

you just connected to Z3 pin 15. Run the other end of this wire to the

CO25953 pin 10.

 

15.___Grasp the other 33 ohm resistor and solder it to the 74LS158 pin 4

(this is one of the ones you have previously piggy-backed.) Now take the long

piece of wire you had previously connected to all of the pin 1s of the rams

and solder this to the free of your resistor.

 

16.___Now take the metal bottom and place the motherboard back into this

protective housing.

 

17.___At the front of your computer on the lefthand side you will find R108.

Desolder the end of this resistor closest to the front end of the computer.

Solder a short wire to the new free end of this resistor, put heat shrink on

the connection, and connect the wire to pin 11 of the CO25953.

 

18.___Our next chore is to locate U6 which can be found near the center of

the front end of the motherboard. Please be careful as the traces on this pc

board are very delicate and will not be able to tolerate much abuse. Gently

desolder pins 23 and 24 of U6. The best way to do this is take your solder

wick, place it against the leg to be desoldered,and heat it until you see the

solder beginning to flow into the wick. Turn the motherboard over and make

sure all the solder is off of the pin on this side also. Repeat this step

with pin 24 also. Then take a small, flat-bladed jeweler's screwdriver and

use it to push the pins back and forth a bit. This will free up the pins and

allow you to remove them easily and not tear the living daylights out of the

board! Turn the motherboard back with the parts side up, and use that same

jeweler's screwdriver to pry pins 23 and 24 of U6 out of the board. Leave

them extended in a horizontal direction, snip the thin part of the leg off,

thus leaving the fat parts of these 2 legs for you to connect to later.

 

19.___Cut a small piece of wire, and strip either end. Connect one side of

this wire to the land where pin 23 of U6 used to be. Fasten the other end of

this wire to CO25953 pin 1.

 

20.___Cut a small piece of wire, and strip either end. Connect one side of

this wire to the land where pin 24 of U6 used to be. Fasten the other end of

this wire to CO25953 pin 2.

 

21.___OPTIONAL!:Get your second cup of coffee.

 

22.___Cut a short piece of wire, strip both ends, and connect one side to the

74LS158 pin 1, and the other side to U17 pin 30.

 

23.___Cut a short piece of wire, strip both ends, and connect one side to the

74LS158 pin 2, and the other side to U23 pin 15.

 

24.___Cut another short piece of wire, strip both ends, and connect one side

of this wire to the 74LS158 pin 3, and the other end goes to U23 pin 16.

 

25.___Cut another short piece of wire, strip both ends, and connect one side

to the 74LS158 pin 15, and the other end to pin 8 of the same chip.(74LS158)

 

26.___Cut yet another short piece of wire, strip both ends, and connect end

of the wire to CO25953 pin 6, and the other end to U6 pin 35.

 

27.___Cut another short piece of wire, strip both ends once again, and

connect one side to CO25953 pin 7, and the other end to pin 8 of the same

chip. (CO25953)

 

28.___Cut another short piece of wire, strip both ends once again, and

connect one side to CO25953 pin 9, and the other to U17 pin 26.

 

29.___Connect one end of this wire to CO25953 pin 12, and the other side to

U6 pin 23.

 

30.___Cut a short piece of wire, strip both ends, and connect one side to

CO25953 pin 13, and the other end goes to U6 pin 24.

 

31.___Cut a short piece of wire, strip both ends, and connect one end to

CO25953 pin 14, and the other end goes to the same chip pin 16.(CO25953)

 

32.___Cut yet another short piece of wire, strip both ends, and connect one

end to CO25953 pin 15, and the other end goes to U6 pin 5.

 

33.___Cut another short piece of wire, connect one end to CO25953 pin 3, and

the other end goes to U23 pin 12.

 

34.___Cut another short piece of wire, strip both ends, connect one end to

CO25953 pin 4, and the other end goes to U23 pin 13.

 

35.___Cut one final piece of wire strip both ends, connect one side to

CO25953 pin 5, and the other end goes to U23 pin 14.

 

36.___Check all your wiring, and rearrange it to be pleasing to the eye as

well as functional.

 

37.___Get your SpartaDos 3.2 that has the RD.COM file on it, say a prayer and

load 'er up! If it boots you probably are ok! If not, don't panic, simply go

back through section step by step, you will find it is probably some little

error or oversight.

 

38.___While you have your computer open it would be a good idea to solder the

joystick jacks, the monitor, I/O and power supply ports also. It may save

you a bit of aggravation later on!

 

39.___Reassemble your upgraded computer by placing the top metal cover back

over the motherboard. Turn all twist tabs and then insert the appropriate

screws. Gently plug the keyboard back in, position it in its slots in the

cabinets, and then place the cabinet top on. Turn over and insert all screws.

While you have it out, why not use a bit of cleaner on it to make it sharp!

If you don't have SpartaDos, then Run, don't walk to your favorite computer

store and get it!

 

For you programming types, here are the control numbers for location 54017

(PORTB).

 

#####################################

 

Bank # Control # Hex #

 

#####################################

 

Bank 1 ------->131----->83

Bank 2 ------->135----->87

Bank 3 ------->139----->8B

Bank 4 ------->143----->8F

Bank 5 ------->163----->A3

Bank 6 ------->167----->A7

Bank 7 ------->171----->AB

Bank 8 ------->175----->AF

Bank 9 ------->195----->C3

Bank 10 ------->199----->C7

Bank 11 ------->203----->CB

Bank 12 ------->207----->CF

Bank 13 ------->227----->E3<--|

Bank 14 ------->231----->E7<--|130XE

Bank 15 ------->235----->EB<--|Banks

Bank 16 ------->239----->EF<--|

 

#####################################

 

It is recommended to use SpartaDos 3.2, but you can also use MYDOS 4.1

or higher, and also Topdos 1.5 and higher with the 320k series of upgrades.

 

Enjoy your 320K 65XE!

 

Scott Peterson

Edited by Guitarman

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Mmmm...this applies to a 130XE as well?

 

The 65XE 130XE/320K Upgrade!

 

by Scott Peterson

 

I have written the following documentation in such a manner that you can

use it to help you keep track of your progress as you assemble this memory

enhancement. Simply place a check in the space provided as you proceed. This

will allow you to readily follow your progress, and pick back up where you

left off if you should have to stop.

 

Once you have finished this upgrade you will then have in your possession an

Atari 65XE with 320K of total ram. This is broken down into chunks of 64K of

standard ram, and 265K of page mapped ram. This upgrade is 100% compatible

with the previous 130XE/320K upgrade and therefore will run all programs that

the earlier enhancement ran.

 

Disclaimer:

 

The Author nor this BBS claim any responsibility for any type of damages

incurred by do this modification

 

The equipment you will need is:

 

A: A medium sized Phillips head screwdriver.

 

B: A very small jeweler's screwdriver with flat blade.

 

C: Soldering wick (recommend Chem-Wik .100 inch size), or vacuum desoldering

pump.

 

D: Soldering station (like Weller model WTCP), or LOW wattage soldering

pencil of the 15-25 watt variety.

 

E: Small pair of needle-nosed pliers.

 

F: #30 gauge wire (Jameco #130 BE)

 

G: Wire stripping tool for #30 gauge wire ("Clip and Strip" Jameco #CAS-130).

 

H: Heat shrink tubing or black electrical tape (tubing preferred).

 

I. Small pair of wire snippers.

 

J: Optional: Small carpet sample or blanket.

 

The parts you will need are:

 

A: Z1-------> 74LS158

 

B: Z2-------> CO25953 (Custom chip by Atari)

 

C: Z3-Z10---> 256K Ram chips #41256-150 (8 required)

 

D: R1,R2----> 33 ohm 1/4 watt resistors (2 required)

 

And here we go.................

 

1.___Place carpet sample or small blanket on a clean, uncluttered workspace

that is well lighted.

 

2.___Situate all tools and parts on one side of your workspace.

 

3.___OPTIONAL: Get a fresh cup of coffee!

 

4.___Place 65XE face down on carpet. Remove all screws holding cabinet

together. Turn unit over. Remove top of cabinet and lay it in a safe place.

 

5.___Gently pull upward with fingertips on mylar extending from keyboard and

remove it from its connector. Place this keyboard assembly with the top of

the cabinet. Place screws in a small container so they won't be misplaced.

 

6.___Take needle-nosed pliers and turn all twist tabs on metal shield so it

may be easily removed. Remove all screws from outer edges of PC Board and

then place screws in your container, and the top and bottom shields along

with the bottom of the cabinet should be placed with the rest of the 65xe

cabinet.

 

7.___Place all ICs in front of you and proceed with the following:

 

a.___Bend up pin number 15 on all 8 of the 41256 rams. Then snip off the thin

part of the leg so all you have left of pin 15 is the "stub" or fat portion.

Do this on all 8 rams.

 

b.___Bend up all pins with the exception of 8 and 16 on the 74LS158. Leave

the legs on 8 and 16 long, and snip the thin part off all other pins on this

chip.

 

c.___Bend up all pins with the exception of 8 and 16 on the CO25953. Leave

the legs on 8 and 16 long, and snip the thin part off all other pins on this

chip.

 

d.___Take both 33 ohm resistors and snip the leads so their is 1/4 of an inch

of lead left on either end of each of these resistors.

 

e.___Place these chips to one side, and position the 65XE motherboard in

front of you. Locate IC numbers U9 through U16. You will find them running

along the left side of the motherboard. Take a piece of tape or a small black

magic marker and place a small mark next to the IC that is labeled U12. You

see the wisdom of doing so later on in this documentation.

 

8.___Proceed to piggy-back ICs Z3 thru Z10 inclusive on top of ICs U8 thru

U15 inclusive. Please take your time and be sure that each chip is facing

the same direction as the integrated circuit below it. Do a good job

soldering so not only will this upgrade work well but also will be pleasing

to the eyes when you show it off to your admiring friends!

 

9.___Cut 7 small pieces of #30 gauge wire, and use these to connect all 8 of

the pin 15s of the piggy-backed rams.

 

10.___Gently turn the 65Xe motherboard over exposing the underside to your

trusty soldering iron. Cut 7 more small pieces of #30 gauge wire and then

proceed to jumper all the pin 1s of the rams. Cut another piece of #30 gauge

wire approximately one foot long and solder it to pin one also and then run

it through a convenient hole in the motherboard. Turn the motherboard back

up with parts side once again smiling up at you.

 

11.___Grasp the 74LS158 and proceed to piggy-back it on top of an IC on the

motherboard labeled U24 which you will find at the front right of your

computer. Make sure it is facing the same direction as the chip you are

placing it on top of and proceed to solder pin 1 of the 74LS158 to pin one

of U24. Next solder pin 16 of the 74LS158 to pin 16 of U24.

 

12.___Grasp the CO25953 IC and proceed to piggy-back this gem on top of U2.

U2 can be found approximately in the dead center of your 65XE motherboard.

Again, please make sure both chips are facing the same direction. Remember,

a slow, sure job is often-time the fastest job overall! Proceed the solder

pin 1 of the CO25953 to pin 1 of U2. Next, solder pin 16 of CO25953 to pin

16 of U2.

 

13.___Grasp one of those 33 ohm resistors you have previously trimmed and

solder one end to pin 15 of Z3. Z3 you ask? Why that is the chip which has

been piggy-backed on top of U12. U12---you know that one! that's the chip

we so wisely marked before we started!

 

14.___Cut a short piece of wire and attach it to the free end of the resistor

you just connected to Z3 pin 15. Run the other end of this wire to the

CO25953 pin 10.

 

15.___Grasp the other 33 ohm resistor and solder it to the 74LS158 pin 4

(this is one of the ones you have previously piggy-backed.) Now take the long

piece of wire you had previously connected to all of the pin 1s of the rams

and solder this to the free of your resistor.

 

16.___Now take the metal bottom and place the motherboard back into this

protective housing.

 

17.___At the front of your computer on the lefthand side you will find R108.

Desolder the end of this resistor closest to the front end of the computer.

Solder a short wire to the new free end of this resistor, put heat shrink on

the connection, and connect the wire to pin 11 of the CO25953.

 

18.___Our next chore is to locate U6 which can be found near the center of

the front end of the motherboard. Please be careful as the traces on this pc

board are very delicate and will not be able to tolerate much abuse. Gently

desolder pins 23 and 24 of U6. The best way to do this is take your solder

wick, place it against the leg to be desoldered,and heat it until you see the

solder beginning to flow into the wick. Turn the motherboard over and make

sure all the solder is off of the pin on this side also. Repeat this step

with pin 24 also. Then take a small, flat-bladed jeweler's screwdriver and

use it to push the pins back and forth a bit. This will free up the pins and

allow you to remove them easily and not tear the living daylights out of the

board! Turn the motherboard back with the parts side up, and use that same

jeweler's screwdriver to pry pins 23 and 24 of U6 out of the board. Leave

them extended in a horizontal direction, snip the thin part of the leg off,

thus leaving the fat parts of these 2 legs for you to connect to later.

 

19.___Cut a small piece of wire, and strip either end. Connect one side of

this wire to the land where pin 23 of U6 used to be. Fasten the other end of

this wire to CO25953 pin 1.

 

20.___Cut a small piece of wire, and strip either end. Connect one side of

this wire to the land where pin 24 of U6 used to be. Fasten the other end of

this wire to CO25953 pin 2.

 

21.___OPTIONAL!:Get your second cup of coffee.

 

22.___Cut a short piece of wire, strip both ends, and connect one side to the

74LS158 pin 1, and the other side to U17 pin 30.

 

23.___Cut a short piece of wire, strip both ends, and connect one side to the

74LS158 pin 2, and the other side to U23 pin 15.

 

24.___Cut another short piece of wire, strip both ends, and connect one side

of this wire to the 74LS158 pin 3, and the other end goes to U23 pin 16.

 

25.___Cut another short piece of wire, strip both ends, and connect one side

to the 74LS158 pin 15, and the other end to pin 8 of the same chip.(74LS158)

 

26.___Cut yet another short piece of wire, strip both ends, and connect end

of the wire to CO25953 pin 6, and the other end to U6 pin 35.

 

27.___Cut another short piece of wire, strip both ends once again, and

connect one side to CO25953 pin 7, and the other end to pin 8 of the same

chip. (CO25953)

 

28.___Cut another short piece of wire, strip both ends once again, and

connect one side to CO25953 pin 9, and the other to U17 pin 26.

 

29.___Connect one end of this wire to CO25953 pin 12, and the other side to

U6 pin 23.

 

30.___Cut a short piece of wire, strip both ends, and connect one side to

CO25953 pin 13, and the other end goes to U6 pin 24.

 

31.___Cut a short piece of wire, strip both ends, and connect one end to

CO25953 pin 14, and the other end goes to the same chip pin 16.(CO25953)

 

32.___Cut yet another short piece of wire, strip both ends, and connect one

end to CO25953 pin 15, and the other end goes to U6 pin 5.

 

33.___Cut another short piece of wire, connect one end to CO25953 pin 3, and

the other end goes to U23 pin 12.

 

34.___Cut another short piece of wire, strip both ends, connect one end to

CO25953 pin 4, and the other end goes to U23 pin 13.

 

35.___Cut one final piece of wire strip both ends, connect one side to

CO25953 pin 5, and the other end goes to U23 pin 14.

 

36.___Check all your wiring, and rearrange it to be pleasing to the eye as

well as functional.

 

37.___Get your SpartaDos 3.2 that has the RD.COM file on it, say a prayer and

load 'er up! If it boots you probably are ok! If not, don't panic, simply go

back through section step by step, you will find it is probably some little

error or oversight.

 

38.___While you have your computer open it would be a good idea to solder the

joystick jacks, the monitor, I/O and power supply ports also. It may save

you a bit of aggravation later on!

 

39.___Reassemble your upgraded computer by placing the top metal cover back

over the motherboard. Turn all twist tabs and then insert the appropriate

screws. Gently plug the keyboard back in, position it in its slots in the

cabinets, and then place the cabinet top on. Turn over and insert all screws.

While you have it out, why not use a bit of cleaner on it to make it sharp!

If you don't have SpartaDos, then Run, don't walk to your favorite computer

store and get it!

 

For you programming types, here are the control numbers for location 54017

(PORTB).

 

#####################################

 

Bank # Control # Hex #

 

#####################################

 

Bank 1 ------->131----->83

Bank 2 ------->135----->87

Bank 3 ------->139----->8B

Bank 4 ------->143----->8F

Bank 5 ------->163----->A3

Bank 6 ------->167----->A7

Bank 7 ------->171----->AB

Bank 8 ------->175----->AF

Bank 9 ------->195----->C3

Bank 10 ------->199----->C7

Bank 11 ------->203----->CB

Bank 12 ------->207----->CF

Bank 13 ------->227----->E3<--|

Bank 14 ------->231----->E7<--|130XE

Bank 15 ------->235----->EB<--|Banks

Bank 16 ------->239----->EF<--|

 

#####################################

 

It is recommended to use SpartaDos 3.2, but you can also use MYDOS 4.1

or higher, and also Topdos 1.5 and higher with the 320k series of upgrades.

 

Enjoy your 320K 65XE!

 

Scott Peterson

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easiest one if you have already another 64k installed would be pull out those 1x64kbit devices and put there 1x256kbit ones

this would give you 320kb of ram total - should be enought

Does anything else have to be done to give 320K?

 

I do have instructions and a picture at...

http://www.a8maestro.com/atari/info/memory/mem130xe1.txt

http://www.a8maestro.com/atari/info/memory/mem130xe1.jpg

 

Rick D.

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Holy sh!t! Look at the size of those decoupling caps..

 

Yeah the Scott Petersen 320k is an easy upgrade.. But you loose separate ANTIC/CPU access.. (130xe Extended Video Mode)

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Yeah the Scott Petersen 320k is an easy upgrade.. But you loose separate ANTIC/CPU access.. (130xe Extended Video Mode)

Parts have arrived, but I'm holding off installation until I get some good quality tools. Am I likely to miss the 130XE Extended Video Mode, apart from in demos which use the technique?

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Hello Vectorman0

Are there any documented 130XE RAM upgrades that retain separate ANTIC/CPU access (130xe Extended Video Mode)?

Mine does. Check out the schematics on my homepage (lower part of the page).

 

greetings

 

Mathy

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Hello Dan

 

Do you have any more information, Mathy? i.e., a parts list and instructions?

 

No, sorry, I don't. It works on my XEGS, but my 800XL keeps having problems. I've had somebody else have a look at it. He told me he found an error, but I said I'ld have a look at it at home. Now I can't find the error he mentioned. Either I made an error converting the plans from XEGS to 800XL or I just soldered the wrong wire to the wrong pin or ...

 

And I haven't really done anything on the Atari 8 bit in over two years. (Damn Apple :D )

 

The room here has been redone, now "all I have to do" is find a place for all my stuff (that was temporarely stored in boxes). This will probably take some time....

 

Man, I have to really get back into this.

 

greetings

 

Mathy

 

PS IIRC I found a small error in the schematics. But unfortunately, I can not remember what/where it was. And as I said, most of this stuff is still in boxes.

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Just add this dpdt switch, available at any parts store even radio shack.

 

This is what I did to get the Peterson to access antic again. pad is to the PCB, and pin is to the lifted leg pin of the chip. One position is standard mode 192k all access tied from the board as usual, the other position is 320k mode with antic restored back in to the upgrade.

add this to the peterson 130XE 320k upgrade found here,

http://www.tcpipexpress.com/Hardware/320KXE.TXT

 

 

img-resized.png Reduced 32%post-21949-1231679614_thumb.jpg 365 x 294 (11.68K)//

Are there any documented 130XE RAM upgrades that retain separate ANTIC/CPU access (130xe Extended Video Mode)?
Edited by _The Doctor__

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This is what I did to get the Peterson to access antic again. pad is to the PCB, and pin is to the lifted leg pin of the chip. One position is standard mode 192k all access tied from the board as usual, the other position is 320k mode with antic restored back in to the upgrade.

add this to the peterson 130XE 320k upgrade found here,

 

 

You can just use a single-pole double throw switch if you want to sitch between 192k(128k extended ram)with extended video, and 320k(256k extended ram)without extended video. All you are doing is switching PIA pin 15 between the motherboard and pin 2 of the 74ls158...

Edited by MEtalGuy66

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Is there any differences between the ram chips inside an xl/xe systems and the ram chips usually found on stfm/ste simms boards

 

As i guess the stfm/ste simms boards (and old school pc versions, EDO i think they were called) are plentiful compared to the ram chips used in normal xl/xe systems

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ST/FM had onboard RAM only, STe uses 30 pin SIMMs which predate EDO. EDO AFAIK can't be used on any Atari system, although Fast-Page supposedly can (that is, they can't be plugged in anywhere but can be wired up)

 

ST needs quicker access time RAMs than 8-bitters, although many XEs have 80 ns (?) RAM, which is in fact 3 times quicker than it needs to be.

 

Unsure on the ST - probably needs 60 ns or lower (?) or maybe 70 ns is OK.

 

Some XEs use 4-bit ICs, others use 1 bit ICs. Some old graphics cards (ie ISA) use RAM ICs which are near perfect donors for Atari RAM upgrades.

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Just add this dpdt switch, available at any parts store even radio shack.

 

This is what I did to get the Peterson to access antic again. pad is to the PCB, and pin is to the lifted leg pin of the chip. One position is standard mode 192k all access tied from the board as usual, the other position is 320k mode with antic restored back in to the upgrade.

add this to the peterson 130XE 320k upgrade found here,

http://www.tcpipexpress.com/Hardware/320KXE.TXT

 

 

img-resized.png Reduced 32%post-21949-1231679614_thumb.jpg 365 x 294 (11.68K)//

Are there any documented 130XE RAM upgrades that retain separate ANTIC/CPU access (130xe Extended Video Mode)?

 

This does not create separate antic and CPU access in 320k mode.. What it does do is tie both ANTIC and CPU access to PB4.. On the stock petersen upgrade, ANTIC is left permanently pointed to the MAIN bank. With the addition of this switch, you get 2 modes:

 

1) TRUE 130XE compatability mode:

64k base ram + 128k extended ram =192k total

True seprate ANTIC and CPU access.

CPU access is controlled by PB4

ANTIC access is controlled by PB5

 

2) 320k mode

64k base ram + 256k extended ram = 320k total

Both ANTIC and CPU access are controlled by PB4.

 

I dont choose to do this on my upgrades because I havent noticed it increase compatability with anything (Possibly Newell expansions??).. I just put a switch on pin 15 (PB5) of the PIA that switches it between its original pad on the motherboard and pin 2 of the 74LS158(PETERSEN UPGRADE). This way ANTIC alwayse stays pointed at the MAIN bank in 320K mode.

 

If you do the switch configuration pictured above, in 320K mode both the CPU and ANTIC are switched from MAIN to EXTENDED RAM any time EXTENDED RAM is accessed. This can cause annoying flickering of the display..

Edited by MEtalGuy66

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Never noticed a flicker. I will try it with The wedge, an antic demo or two and the color ansiterm that is being used for telnet/irc. It would seem the mod I use cpu/anitc follow each other and the mod you described antic stays in main no matter what. Neither one of our switches cover all the bases :(

Edited by _The Doctor__

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Never noticed a flicker. I will try it with The wedge, an antic demo or two and the color ansiterm that is being used for telnet/irc. It would seem the mod I use cpu/anitc follow each other and the mod you described antic stays in main no matter what. Neither one of our switches cover all the bases :(

 

It's only going to flicker on an application in which either ANTIC's display list, or the screen bitmap data is stored in the $4000-$7FFF adress range... remember, this is the range of base memory that gets "bank switched" with extended ram..

 

The way you do your switch hookup, you'd have to build "copies" of screen & display list data for each bank, if you wanted to use that adress range for them and not have the flicker, because ANTIC and the CPU are being switched together, no matter what... If you leave ANTIC pointed at base ram, you can leave your screen data and display list there and let the CPU go to whatever bank it needs to run code.. The drawback is that you cant point antic at the extended banks for "page flipping" purposes.. So some would prefer your upgrade, and just make sure the screen & display list are outside of $4000-$7FFF, when not using the extended ram for graphics pages... Others would prefer to leave ANTIC pointed at base ram (for applications that require simultaneous ANTIC access to 3 successive hi-res screens worth of data, and also want utilize extended ram, this is the only way to do it) and then use the extended banks for CPU code... It's just a matter of specific coding requirements/preference, really.. What you could do is add a third swicthing position (See figure below)

 

post-8775-1234982411_thumb.jpg

Edited by MEtalGuy66

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adding the double pole triple throw is probably the least expensive solution so far, but is there a way to get the upgrades to have true antic and cpu banking, perhaps using a few ic's?

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Sure - there have been true banking upgrades for quite a while now. You could even put a rotary switch on one to select all the modes, if you needed them.

 

Bob

 

 

 

adding the double pole triple throw is probably the least expensive solution so far, but is there a way to get the upgrades to have true antic and cpu banking, perhaps using a few ic's?

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