Apple II CPU Hardware and Hardware Projects

 

Csa2 FAQs-on-Ground file: CSA2HDWHACK.TXT rev010

 

 

The Csa2 (comp.sys.apple2) usenet newsgroup Frequently Asked

Questions files are compiled by the Ground Apple II site,

1997, 1998.

 

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The Csa2 FAQs may be freely distributed.

 

Note: To correctly view tables and diagrams on a super-res display,

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____________________________

 

 

 

 

001- What's a good hardware project book for the Apple IIe?

002- How can I use a thermistor to read temperature on my A2?

003- Will a prototyping Slot Board fit all Apple II's with Slots?

004- What is the pin-out for the Apple II series Slots?

005- I've been getting Fatal System Error 0911. Is there a fix?

006- Why does my GS Control Panel keep resetting to the defaults?

007- How do I replace my GS "BatRAM" battery?

008- Is there a program to record/restore Control Panel settings?

009- How I can safely clean out dust from my Apple II?

010- How can I safely remove oxidation from IC pins?

011- After smoke came from my GS the KB doesn't work. What's wrong?

012- What is the mini circuit board near the front of my GS for?

013- How do I add memory to my 1MB Apple IIgs Memory Expansion Card?

014- How can I move my IIgs to a PC tower case?

015- How can I convert a IIgs into a portable IIgs?

016- Where can I get Robot kits to use with my Apple II?

017- Where can I get the chips to expand memory on my AE GS-RAM III?

018- What is a TrackStar? Does it need special software?

019- Could someone please post a resistor color code chart?

020- What advantages does the ROM 3 GS offer vs. the ROM-01 GS?

021- How can my ROM 3 GS + 8MB Sirius card do large file copying?

022- Where can I find a listing of Apple II socket, etc. pinouts?

023- Where can I find Apple II diagrams?

 

 

 

From: Paul Guertin

 

001- Could anyone suggest a good project book for the Apple IIe.

I'm interested in using an old box for tracking the

temperature in a water bath.

 

 

Vernier software publishes a book called "How to Build a Better

Mousetrap" which contains 14 hardware projects for the Apple II. Project

#6 is a temperature probe connected to PDL0.

 

ISBN for the book is 0-918731-16-X.

Vernier Software ( http://www.vernier.com )

2920 S.W. 89th Street

Portland, Oregon 97225 USA

(503) 297-5317

 

----------------------------

 

 

From: Sheldon Simms

 

A good book is _Inside The Apple IIe_ by Gary B. Little. It isn't a

project book, but it does have a good chapter on using the Game I/O

connector for "electronics experiments."

 

 

____________________________

 

 

 

From: Cyrus Roton

 

002- How can I use a thermistor (a resistor which has a variable

resistance related to ambient temperature) to read temperature

on my Apple II?

 

 

You can connect a thermistor to a paddle input and supply a voltage to

the other end. Current flows through the thermistor to charge a .022 mfd

capacitor inside the apple2. When the paddle is read, the apple2

discharges the capacitor and resets a timmer. Then the cap is allowed to

charge. When the charge reaches the trigger level (3.2 volts) the timmer

is stopped and the count is read out.

 

The lower the value of the thermistor, the faster the charge and the

lower the count. Also, the higher the voltage, the faster the charge. A

resistance of about 120K with a 5 Volt supply will give a count of about

250. You can add an external capacitor across the paddle input (to

ground) to increase the charging time (if needed)

 

The formula is (charge) = (input volts) * (1 - exp(-t/RC))

 

So, you can use a supply voltage and external capitor as required to fit

the resistance value of the thermister (or other resistive component).

Probably, the best way to find the correct values woud be to try a

variety of values and plot the "count" as a function of the variable

resistance. Then compare the plot against the resistance curves for the

thermistor (probably not linear), and work out some conversion formula

to use in your program to correlate "count" to temperature.

 

 

____________________________

 

 

 

From: David Empson

 

003- Can I use the same prototyping Slot Board for all of the

different Apple II's with Slots?

 

Prototyping boards certainly would be the same for the II, II+, IIe, and

IIgs. The slots on all slotted Apple IIs are physically identical

 

There are minor differences between the slot signals on the various

machines and on some slots in the same machine, mostly affecting rarely

used special pins. (See Question 004 for more details on signal

differences.)

 

----------------------------

 

 

004- What is the pin-out for the Apple II series Slots; and, what

differences are there in Slot signals from machine to machine?

Here is a quick summary of the Apple II series Slot signals:

 

Pin 1: I/O Select ($Cn00-$CnFF, where n is the slot number).

 

Pins 2-17: Address bus A0-A15.

 

Pin 18: Read/Write.

 

Pin 19: unused on the II and II+. On the IIe and IIgs, this has

composite horizontal and vertical sync on slot 7, and is unused on other

slots, except for slot 1 on the IIe only, which has a diagnostic

function to disable the oscillator on the motherboard.

 

Pin 20: I/O Strobe ($C800-$CFFF).

 

Pin 21: this is the RDY input to the micro on all machines, but it

behaves a little differently in the IIgs, or in a machine with a 65802

installed.

 

Pin 22: this is the DMA pin on all machines. Again, there are special

issues for doing DMA on the IIgs which can cause compatibility problems.

 

Pin 23: this is used for the interrupt daisy chain (out) on all Slots

except 7. In the IIe only, this pin can be connected to the GR signal

(graphics mode enabled) via a motherboard modificatoin.

 

Pin 24: DMA daisy chain out.

 

Pin 25: +5V.

 

Pin 26: Ground.

 

Pin 27: DMA daisy chain in.

 

Pin 28: Interrupt daisy chain in.

 

Pin 29: Non Maskable Interrupt.

 

Pin 30: Interrupt Request.

 

Pin 31: Reset.

 

Pin 32: this is the INHIBIT pin on all machines. This behaves

differently on all three machines: the II and II+ only allow the

$D000-$FFFF ROM area to be inhibited. The IIe allows RAM to be

inhibited as well, but has strange interaction with main and auxiliary

memory. The IIgs only allows this signal to be used if the machine is

running in slow mode.

 

Pin 33: -12V.

 

Pin 34: -5V.

 

Pin 35: unused on the II and II+. On the IIe and IIgs, this is the

colour reference signal on slot 7 only. It is unused for other slots in

the IIe, except for slot 1 where it provides a poorly documented

facility to disable the keyboard address decoding. On the original

IIgs, slot 3 provides the M2B0 signal (Mega II Bank 0) via this pin and

it is unused on other slots. The ROM 3 provides M2B0 for slots 1 to 6.

 

Pin 36: 7 MHz system clock.

 

Pin 37: Q3 - Asymmetrical 2 MHz clock.

 

Pin 38: Phase 1 clock (1.023 MHz).

 

Pin 39: something called "USER 1" on the II and II+, which can be used

to disable all I/O decoding if a modification is made on the

motherboard. On the IIe, this pin provides the SYNC signal from the

micro, which indicates an opcode fetch. On the IIgs, this pin provides

the M2SEL signal, which indicates that a valid slow memory access is in

progress. This pin must be used by IIgs cards that decode the address

without use of the IOSEL, IOSTRB or DEVSEL pins.

 

Pin 40: Phase 0 clock (1.023 MHz).

 

Pin 41: Device Select ($C0n0-$C0nF, where n is the slot number plus 8).

 

Pins 42-49: Data bus D7-D0.

 

Pin 50: +12V.

 

____________________________

 

 

 

from Rubywand

 

005- I've been getting Fatal System Error 0911 and when I do the

internal diagnostic it gives a system bad : 09010001.

Is there a fix?

 

Fatal System Error 0911 and Self-Diagnostic Test 09010001 mean the

same thing: You are, very likely, experiencing an ADB Controller

malfunction.

 

A guess would be that you are running a ROM-01 GS, probably a

ROM-00 machine which has the ROM-01 upgrade. If this is the first time

you've noticed the '0911 problem, it is likely that this is the first

summer you've owned and used this particular machine.

 

Many early GS's come with an ADB IC which malfunctions over a

narrow range of relatively low temperatures. Rooms are normally cooler

during summer; so, this is when the error pops up most frequently. Some

users first notice a plague of '0911 crashes after adding a System

Saver-GS (which increases cooling).

 

'0911 bombs can occur 'any time' but they usually happen at startup

and when doing OpenApple-CTRL-ESC accesses to the Desk Accessories

(CDA's, Control Panel, ...) menu. As the machine warms up, '0911 crashes

tend to become less likely.

The bad news is that there is no 100% fix except to replace the

temp sensitive ADB IC-- hard to do since it is soldered to the

motherboard and, in any case, known-good replacements are difficult to

find.

 

As to _which_ ADB IC-- there are two, the ADB Controller and the

ADB GLU-- our notes say the ADB Controller; but, we could have easily

misidentified the function back then and the ADB GLU IC 'clicks' better

with memories of the fix. (The ADB GLU IC is a bit larger and easier to

reach.)

 

Note: The easiest way to identify the temp sensitive IC is to apply the

fix (below) and see if it works. If it does, fine. If not, it is easy to

move the fix to the other IC. For now, my suggestion is to try the ADB

GLU IC first.

 

Since the problem is coolness, a decent cure is to tape a small 12V

bulb (e.g. a 20-30 ma. panel light bulb) to the top of the ADB IC (a

square IC near the right front of the motherboard). Use duct tape and

try to enclose the bulb and IC in a kind of mini-oven. Run the leads

from the bulb to the +12V Fan power pins near the back left area of the

motherboard.

 

The idea is to quickly warm up the IC. I used a scheme like this on

our early GS and 0911 bombs dropped from 4-5 per day to 2-3 per week. If

you can safely power the bulb via an external power module (e.g. a

calculator or radio 'AC adapter') so that the bulb can be ON at least a

few minutes before powering up the computer, 0911 bombs might disappear

entirely.

 

----------------------------

 

 

006- My GS control panel keeps resetting to the defaults and

forgetting the date between power-ups. What's wrong?

 

Most likely, your battery-- also called the "BatRAM battery" needs

to be replaced. When the GS is OFF, the battery supplies power to the

clock and its attached 256-byte RAM. This small RAM is where Control

Panel settings are 'remembered'.

 

If, upon power-up, the GS believes the Control Panel settings have

been messed up due to a low battery, it will reset the settings to their

default (check-marked) positions.

 

----------------------------

 

 

007- How do I replace my GS "BatRAM battery"?

 

The standard GS battery is a 3.6V Lithium type rated at 1.2AH. It

is called the "BatRAM" battery because it keeps the Battery RAM and

Clock IC going when you turn OFF power. To get to the battery, you must

pop out the Power Supply.

 

If you have a ROM 03 GS, you can slip out the old battery and slip

in 'one like it'. On the ROM 01 GS, you will need a Lithium battery with

leads you can connect to cut-off leads from the old battery-- about 3/4"

each-- remaining on the motherboard. Be sure to mark the "+" lead on the

motherboard with white-out.

 

Night Owl Productions used to sell a convenient "Slide-On" Lithium

battery made by Tadiran. It came with springy ends that would slip over

the cut-off leads from the original GS battery.

 

Radio Shack sells a few models of 3.6V Tadiran Lithium batteries.

Mostly, these have smooth ends and are intended to fit into a holder--

for example, one model is "AA" size. Connecting an insulated size AA

holder and using a size AA 3.6V battery is one way to handle BatRAM

replacement now while making future replacements easier.

 

Another Radio Shack 3.6V Tadiran Lithium battery comes as a small

rectangular insulated pack with red and black wires going to a plug.

From the catalog illustration, it appears that the plug could be fitted

onto the cut-off leads if these were long enough to be shaped to match

the plug's connectors. (If you decide to have long cut-off leads, it's a

good idea to slip heat-shrinkable tubing over the leads to insulate them

for most of their length.)

 

It may be that your best bet for getting a good BatRAM replacement

battery is All Electronics (800-826-5432; http://www.allcorp.com ).

Their last catalog lists two 3.6V 2.5AH Lithium batteries with wire

leads which should fit well in a ROM-01 GS for $3.50 each. They also

offer a 3.6V "AA size Lithium battery" ($3.50) which looks good for

computers with AA size holders.

 

 

If you like, you can always solder, crimp, etc. insulated leads

going to some plug or socket which matches the connector of a particular

battery you'd like to use. For connecting bare leads, Duncan Entwisle

suggested using the springy connectors from a Radio Shack electronics

experimenter kit to connect a new battery's leads. Another way is to

use "wire nuts". Should you do any soldering to the cut-off leads, try

to avoid long heat exposure-- you do not want to melt the connection at

the motherboard.

 

Make sure that the new battery's "+" lead connects to the "+" lead

on the motherboard. Since, possibly, you will be joining bare leads to

bare leads, you could end up with more bare wire than you are

comfortable with. Check that the bare leads do not touch anything they

should not. Bend the leads as required and position the new battery so

that nothing will bump into the Power Supply when it is replaced.

 

The usual recommendation for this kind of work is that the computer

be OFF. This reduces the risk of damage should a bit of solder, a wire,

etc. fall onto the motherboard.

 

GS users are sometimes shocked to discover that a replacement

battery may cost $8 to $13. This has led to suggestions that 2-3

standard 1.5V cells in a holder be used. While any number of lower-cost

replacement setups can work, this is pretty close to a classic 'you get

what you pay for' situation. Regular 1.5V cell combos reportedly crater

in about a year. A 3.6V 1.2AH Lithium battery is routinely good for at

least 5 years.

 

Our old Nite Owl battery is going on year 7 or 8. That's a lot of

years without having to worry about burst and leaking cells or needing

to pull the Power Supply and mess with swapping-in replacement cells.

 

----------------------------

 

 

008- Is there a program to record my Control Panel, etc. settings

and restore them after the GS BatRAM battery is replaced?

 

Reference: FAQs Resource file R007BATRAMM.SHK

 

Yes. A number of users have created programs to Save and Restore

BatRAM values. The one included as a FAQs Resources file is named

"BATRAMMER". It is in file R007BATRAMM.SHK. Use ShrinkIt or GS-ShrinkIt

to unpack the file.

 

 

____________________________

 

 

 

From: Adalbert Goertz

 

009- How can safely clean out dust from my Apple II's

motherboard, case, and expansion cards?

 

I use a Dustbuster. Block one exit vent and aim the other vent as a

blower into the computer. That Dustbuster has strong lungs!

 

____________________________

 

 

 

From: George Rentovich

 

010- I'm afraid that oxidation on pins may be causing bad

contacts and memory problems. How can I remove the

oxidation without resorting to sand paper?

 

Tarn-X works great for removing oxididation from chip pins without

a lot of work or risk in harming the chips.

 

Soak the chips in a shot glass until all black oxidation is gone;

then, remove the chips and put them in another shot glass with alcohol

to rinse. I use a third shot glass with alchol again to be sure and,

then, take out the chips and let dry.

 

 

____________________________

 

 

 

From: Rubywand

 

011- Recently I was using my GS and smoke started coming from the

inside. Now my ADB peripherals (KB and mouse) don't work! It

looks like the smoke came from an 8-legged module in the upper

leftmost corner right behind the composite video connector and

ADB jack. What's wrong? How can I fix my GS?

 

The module you are talking about is L2 "D-15C". This is an 8-pin

thing containing four inductors (coils). Three inductors are used. They

are in series with the ADB Desktop connector. Evidently, one of the

inductors burned out. This would explain the smoke and the loss of ADB

functioning.

 

The three inductors run ...

 

pin 1 to pin 8

pin 2 to pin 7

pin 3 to pin 6

 

You can use an Ohm meter to detect which one is open. (Example: the

correct reading from pin 2 to pin 7 would, probably, be less than an

Ohm.) Since the pin2-pin7 inductor connects to +5V on the pin7 side, it

is the best candidate for a burn out should pin2 some how have been

shorted to ground.

 

 

Note: Jon Christopher reported that when his L2 module bombed it was due

to a short in a spliced-on KB cable. It turned out that the resulting

burn out fused some of the inductors together inside the module. So, if

you detect any break after such a burn out, it is probably best to just

remove the module and replace all three inductors.

 

 

Replacing the inductors should be fairly easy, although it will

probably be necessary to remove the motherboard. The value of the

inductors is not critical, so 15-20 turns of small wire-- like wirewrap

wire-- wrapped on a pencil or screwdriver shaft will make a small coil

you can use. Make three coils.

 

After removing the damaged L2 module, use an Ohm meter to check for

a short to ground at pins 1, 2, and 3. (If, as in the case of a short in

a spliced-on KB cable, you know where the short is/was, you can skip

this check.) Eliminate the short before continuing.

 

Solder your home-brew coils in place (pin 1 to pin 8 for the first

coil, etc.), put everything together, and your GS should be as good as

new.

 

 

----------------------------

 

 

012- My ROM-01 GS has an odd postage stamp size circuit board

tacked onto the motherboard near the front edge. What is the

board for?

 

The circuit on the mini-board is a low-gain 1-transistor amplifier

which seems intended mainly as a buffer/voltage-level shifter between

the 'old Apple' sound output of the Mega Chip and Op Amps which drive

the Speaker and Sound jack.

 

On the underside of the motherboard, beneath the boardlette, a

surface-mounted resistor (SR1) has been scratched out. Leads from the

mini-board run to SR1's connection points as well as Ground and a +12V

supply point near Op Amp UM12.

 

The circuit does not appear in the GS 'Hardware Reference ROM-01

schematics; but, it is shown in ROM-03 schematics. Some ROM-01 GS's do

not have the mini board; so, it seems likely that the circuit was

included on-motherboard in later ROM-01's and all ROM-03's. By the way,

the circuit was certainly installed at the time of manufacture and was

not part of the standard ROM-00 to ROM-01 upgrade.

 

----------------------------

 

 

013- I have 256kB on my 1MB Apple IIgs Memory Expansion Card.

How do I add more memory?

 

The standard Apple IIgs 1MB Memory Expansion card can be usefully

configured for 256kB, 512kB, and 1MB.

 

 

For 256kB, the top left 8 sockets (i.e. the left half of the top

row) should be filled. No jumpers should be placed on the pins near the

lower right end of the board.

 

 

XXXXXXXX--------

----------------

O O (no Jumpers)

0 0

 

 

For 512kB, the entire top row of sockets should be filled. The

bottom

pair of pins should be jumpered.

 

XXXXXXXXXXXXXXXX

----------------

O O

0-0 Jumper bottom pair

 

 

For 1MB, all sockets should be filled. The top and bottom pairs of

pins should be jumpered.

 

XXXXXXXXXXXXXXXX

XXXXXXXXXXXXXXXX

O-O Jumper top and bottom pairs

O-O

 

To get the full IIgs mem card upgrade to 1MB you can order a set of

24 41256 mem IC's from Alltech (760-724-2404) for $24.00.

 

____________________________

 

 

 

From: SuperTimer

 

014- I've heard that some have moved their IIgs's to PC tower cases.

Is this hard to do?

 

It is not hard to do at all...

 

I mounted the motherboard with the expansion cards going horizontal

in relation to the ground (you need to drill some extra holes in the

tower case because the GS has different mounting holes than the PC). The

cards are light enough that they stay put this way. The only time this

could be a problem is with unusually heavy cards, like the Focus or

MicroDrive units...

 

The cards don't line up with the openings on the case, but that's

not a problem because Apple cards, unlike PC cards, have ribbon cable

extended DB connectors that can be mounted on the openings at the back

of the case...

 

For the power supply, I rewired a PC power supply to feed the GS.

The voltages are the same, so simply match +5V with +5V, +12V with +12V,

-5V with -5V, -12V with -12V, and the grounds and your GS will be ready

to run!

 

The PC power supply (250 watts) and fans have a benefit...my GS is

more stable now than it was in its native case. I recommend this

upgrade for those who feel up to it. Use a full tower case for the best

results and most room to work with.

 

----------------------------

 

 

015- I recently picked up a spare GS from a flea market and

would like to convert it into a portable. Has anyone done this?

 

Yes. Tony Diaz has an article describing a couple conversions on

his web site at

http://www.apple2.org/AppleIIgsPortables.html .

 

____________________________

 

 

 

From: Erick Wagner

 

016- Where can I get Robot kits to use with my Apple II?

 

If you have a an RS-232 interface (2400 or 9600bps) you might

consider a kit from Lynxmotion ( http://www.lynxmotion.com ). They sell

various robot and robotic arm kits that utilize hobby R/C servo motors.

Scott Edwards Electronics and several other companies sell devices that

allow you to control up to 8 servos per board.

 

You'll have to write all of the software yourself (sending commands

to identify a servo and a position value).

 

----------------------------

 

From: Rubywand

 

A good source of current information on robot making, Parallax

BASIC stamp programming, and related projects is Nuts & Volts Magazine

(800-783-4624; http://www.nutsvolts.com ).

 

___________________________

 

 

 

From: Dick Pirong

 

017- Where can I get the chips to expand my AE GS-RAM III memory

Expansion card to 4MB?

The Applied Engineering GS-RAM III uses 20-pin "Zip" package 1M x 4

DRAMs (NEC D424400V-80 or OKI H5144024-70). Mike Morton led me to a

supplier in the Computer Shopper magazine. (Thanks Mike.) The supplier

is L.A.Trade (800-433-3726; http://www.4LATrade.com/memmisc.htm ). I

now have a total of 5 megs in my ROM 3 and all is well.

 

____________________________

 

 

 

From: Bill Whitson

 

Related FAQs Resource: R022TRKSTAR.TXT (text file)

 

018- What is a TrackStar? Does it need special software?

 

A TrackStar is a single board Apple 2 computer that plugs into an

expansion slot in a PC Clone. With this board (and an A2 disk drive) a

PC can run Apple II software. See the FAQs Resource file R022TRKSTAR.TXT

for details.

 

 

----------------------------

 

 

From: me@here.com

 

 

Yes, TrackStar does need some software. I have it; it's less than

30k in a zipped file.

 

____________________________

 

 

 

From: Rubywand

 

019- Could someone please post a resistor color code chart?

 

 

Color Digit Multiplier (when 3rd band) Example

 

Black 0 x1 -- Red Red Black = 22 Ohms

Brown 1 x10 -- Blue Grey Brown = 680 Ohms

Red 2 x100 -- Orange White Red = 3900 Ohms

Orange 3 x1000 -- Yellow Violet Orange = 47k Ohms

Yellow 4 x10000 -- Red Green Yellow = 250k Ohms

Green 5 x100000 -- Orange Orange Green = 3.3M Ohms

Blue 6 x1000000 -- Red Yellow Blue = 24M Ohms

Violet 7 x10000000 -- ...

Grey 8 x100000000

White 9 x1000000000

 

Gold - x 0.1 -- Brown Brown Gold = 1.1 Ohms

Silver - x 0.01 -- Orange White Silver = 0.39 Ohms

 

 

Tolerance (4th band)

 

Red is <5% (courtesy of Edhel Iaur)

Gold is 5%

Silver is 10%

no color is 20%

 

Example: Grey Red Orange Gold is 82k Ohms +/- 5%

Example: Brown Black Green Silver is 1M Ohms +/- 10%

 

Note: carbon resistors almost always err on the high side.

 

____________________________

 

 

 

From: Mitchell Spector

 

020- What advantages does the ROM 3 GS offer vs. the ROM-01 GS?

 

The ROM 3 Apple IIgs offers many minor enhancements vs. the ROM-01

which make the machine more functional and pleasant to use:

 

- You get a machine that is about 5-10% faster for GUI, floppy disk

loading and RAM Disk operations (due to updated smartport firmware

and System 5 tools being in ROM).

 

- A machine that is more flexible when working with AppleTalk and

slots (you don't have to give up an extra slot and you can stick a

card in slot 4 and still use the mouse in GS/OS).

 

- A nicer text Control Panel that lets you resize RAM Disk with a

warm-boot and a cleaner way to size it too (no min/max size junk).

Also a 'Mouse' menu and other existing things cleaned up and made

better.

 

- A just over 1 megabyte of RAM built-in to start off with; so, you

can have 5 MB of DMA compatible memory in total.

 

- The MB0 signal provided in slots 1 through 6, so you can stick

in a Video Overlay Card _and_ Second Sight in together, and not

worry about having to reserve slot 3.

 

- Hardware shadowing of text page 2 with Alternative Display Mode

(no slowing down your system to a crawl when you see a screen full

of 2's running 8-bit software).

 

- A newer ADB keyboard microcontroller with built-in sticky keys,

keyboard mouse and compatibility with the indicator LEDs

on extended keyboards.

 

- A removable Lithum battery (in a snap case. Just pop the old one

out when your clock and Control Panel settings stop working).

 

- Less power consumption and electrical noise from the motherboard,

 

- A set of pins (location 'S1') on the motherboard to make the text

Control Panel disappear, making your GS settings tamper proof where

young children are around

 

 

There are even a couple of more goodies, like the Step/Trace

commands in Monitor or the improved disassembler. Even if you are not a

programmer, they're handy for peeking at SHR graphics still in memory

(from Monitor hit 'S' and then the return key).

 

Things like sticky keys and mouse keyboard come in handy too-- like

if you are eating or drinking with one hand, you can still reset the

computer using the other.

 

The down side is that some old GS games and demos won't run. However

many of the more worthwhile ones have been patched.

 

____________________________

 

 

 

From: Scott G

 

021- How can my ROM 3 GS + 8MB Sirius card do large file copying?

 

An error in the Sirius manual (a 1 page paper) recommends that ROM

3 users remove one of the SIMM modules since the ROM 3 has 1MB and 8MB

is max. When I did this, the GS reported 8MB, but copying large groups

of files or large files (>800k) failed. When I put the missing SIMM

back, the GS still reported 8MB, but the file copy problems vanished.

It appears that the Sirius needs eight 1MB SIMM modules for 8MB even on

a ROM 3.

 

____________________________

 

 

 

From: Charles T. Turley

 

Related FAQs Resource: R023PINOUTS.TXT (text file)

 

022- Where can I find a listing of Apple II socket, etc. pinouts?

 

See the FAQs Resource file R023PINOUTS.TXT.

 

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From: David Wilson

 

023- I have several different model Apple II computers ranging from

a II+ up through a IIgs. Does anyone know where I can get

diagrams for these machines?

 

I know of three books with Apple ][+ schematics:

 

Jim Sather's "Understanding the Apple ]["

 

"The Apple II Circuit Description" by Winston D. Gayler

published by Howard W. Sams & Co (ISBN 0-672-21959-X)

 

Apple II Reference Manual (1979)

 

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From: Mike Westerfield

 

"Understanding the Apple II," by Jim Sather, has a complete set of

II+ schematics, as well as more information about putting them to use

than the official Apple manual.

 

It's available from Byte Works for $14.95. Check out our list of

software and books at www.hypermall.com/byteworks. And if you'd like a

printed copy of our catalog, just send me a snail-mail address.

 

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From: Rubywand

 

The IIe Technical Reference 1986 edition includes diagrams and an

annotated firmware listing. Probably, the IIc and IIc/IIc+ Technical

Reference manuals are similar to the IIe Technical Reference-- not sure,

since I have not seen a IIc manual.

 

The Apple IIgs Hardware Reference has a good set of schematics. The

First Edition covers the ROM-01. The Second Edition covers ROM-01 and

ROM 3. Unfortunately, there is no firmware listing.