Urchlay

November 6, 2019

> When we all die in the coming Mad Max apocalypse, the cockroaches that gain sentience afterwords will probably be playing Donkey Kong on them.

And Keith Richards shall be their King, upon his throne of Tupperware...

November 4, 2019

> what I would like to find is say the Holmes.. but download it all in a zip??

The Holmes archive isn't what I'd really call well-curated or well
organized. It has a lot of duplicate files and "cruft", e.g. badly-cracked
games whose crack screens require a particular OS revision (XL or 800
rev B) even though the game itself works on any Atari OS.

Also a lot of corrupt files, some truncated, some that look like they've
been "cooked" by having the ASCII carriage returns removed (or ASCII
carriage returns added after every ASCII linefeed byte).

Also multiple "versions" of the same game, slightly different binary
load file structure, but they end up loading exactly the same code/data
into memory. Or, same code/data except for different cracked-by intros.

Basically it was someone's Atari 8-bit collection he'd been adding to for
years, and at some point he released what he had as a 3 CD set sometime
in the late 90s or early 00s... which hasn't been updated since then.

Not saying Holmes is utter crap or a waste of space, but I am saying
it should be the last place you look for something, if you can't find
it elsewhere.

These days, 3 CDs isn't that much bandwidth or storage, you could just
download the whole thing. I don't know how people do that on Windows or
Mac, but I'm sure a lot of people here do (I use wget on Linux, which
does exist for Windows AFAIK).

November 2, 2019

> NO video signal at all

Is there audio? Without a drive attached, do you hear the SIO polling
"fart" noise? If you hold down Start, do you get the cassette boot
buzzer?

October 23, 2019

Lot of useful suggestions here...

> You could probably mod a 2532 EPROM to work, with some remapping of the CS to OE pins (50% chance of it working without needing an inverter.. hmm)

Not a 2732? I ask because I actually have some 2732s in a drawer (used
to use them for 2600 carts).

I think the high rom would have the active high chip select, it would
need an inverter like the 2600 does.

> quickest 'fix' here is probably to just take an 8K Atari BASIC mask ROM (2364) out of an XE or XL and plug it directly into one of the sockets of this 8K PCB leaving the other empty and it should work

Yeah, except I don't wanna break a working machine, plus all my XLs have
built in Rev B (ugh). Maybe Best/B&C can sell me one.

> you could directly modify this 8K PCB to take a single more common 2764 EPROM

That looks like something I could do, and I've likely got 2764s lying
around (or can order some, they're still pretty common I think). I know
I've got at least one 27256 (also 28 pins), used it for a 2600 multicart
that's still in the closet somewhere.

So a 2364 mask ROM is 24 pins, but a 2764 EPROM is 28. Was there ever
such an animal as a 24-pin 8K EPROM (2564 maybe)? My old EPROM programmer
could definitely handle the old chips, it looks like late 70s tech,
an RS232 GTek.

Really the deal here is, I'm willing to spend time & effort to fix this
old cart, but not very much money. I don't absolutely *need* it working,
I only have one machine without built-in BASIC and I have a working
BASIC cart for it. The dead BASIC cart has some sentimental value,
that's about all.

Also I got a BASIC XL cart that works nicely, just in case :)

October 22, 2019

How did you dump the working Rom? Burner or by program on the Atari?

K (Binary Save) option from DOS 2.5 menu. I have an old burner but
haven't yet found its power supply or the 9-to-25 pin RS232 cable it
needs (minor miracle that I found the burner actually, I'm not what
you'd call organized).

Swapping would matter if they both worked as you'd get the invalid startup flags and Self Test as a result.

Not on this board. I didn't figure this out myself (credit goes to joe_z
on IRC, aka "Joey Z" on AA I think). The way this board works is, one
ROM has an active high chip select, and the other has active low. The 2
chip selects are connected together, and also connected to the A12 pin
on the cart port.

So when A12 is low, the low ROM gets selected, regardless of which
physical socket it's in.

When I dump the working ROM, I get an identical file regardless of which
socket the ROM is plugged into: the lower 4K is the BASIC code and the
rest (if I save 8K) is all $FF.

This makes sense in another way: if there were high and low sockets,
there would have to be a chip or at least some other components on the
board to select between them based on A12. But all this board has is
the 2 sockets and the filter cap, no other components.

I dunno why I'm going into such detail now, except maybe that this
info will someday help someone else. One of my ROMs is fried for sure,
so this cart won't be fixed unless I can find a replacement somewhere.

October 22, 2019

Alternatively, just try each IC on it's own in the low slot.

Edited. Originally said:

I dunno which socket is low or which is high... but you're right: with
either ROM in the right socket, I get self-test. With either ROM in the
left, I get greenscreen.

...But I was mistaken: one of the ROM chips causes greenscreen
no matter which socket it's in, and the other one allows booting no
matter which socket it's in.

From what I can tell, the 2 sockets are electrically identical: the pins
are wired 1-to-1, 2-to-2, etc for all 24 pins. So if both ROMs were
working, it wouldn't matter if I swapped them. Since one of the ROMs
causes greenscreen no matter which socket it's in, I have to assume that
one is bad, maybe internally shorted so it shorts the address/data buses.

I went ahead and dumped the one ROM that works. It matches the bottom 4K
of a BASIC revision A dump (NOT rev C as the sticker on the front claims).

October 22, 2019

So, no crossed address or data lines?

That is a mystery then. Of course if it's just the bare board I assume you plugged it in the right way?

Heh. I assumed that too. Turns out I'm dumb and wrong. When it's plugged
in the right way, chips sockets facing the back of the Atari, the bare
board doesn't crash the machine. It boots to self-test, and the memory
test shows only 40K of RAM available. You have solved the mystery,
and I now have doubts about my own brain...

So it looks like the board is actually OK, and the ROMs are fried. More
specifically, only one is fried (I get self-test when the left ROM only
is in, and greenscreen with the right one only).

These ROMs aren't pin-compatible with 27xx series EPROMs I don't think,
and there's not room in the cart case for one of the adaptors, so I
guess the cart is permanently dead. Maybe I can reuse the shell for one
of the cart boards the AA store sells...

I even think I know what killed the ROM: the little springloaded wire
that puts pressure on the cart shell's lid was out of place, and probably
touching the board somewhere.

October 22, 2019

Re removing the chips - try that, the cart should then just make the system appear as 40K, if it crashes then it means it's likely the Roms are OK but the board has a fault.

I'd gotten that far before posting it here... the Atari behaves the
same with this board plugged in, whether the roms are in it or not
(greenscreen of death, no speaker pop).

If I can fix the board, the roms still might be bad, but bad roms should
cause the Atari to crash *after* the sceen turns black and the speaker
pops (the OS zeroes all the HW registers before it inits/runs the cart).
At least, if the chips work but the contents are scrambled. If the
roms have died with an internal short, I might get symptoms like I'm
getting... but then the rom-less bare board wouldn't cause the same thing.

I'm just at a loss for what the fault in the board might be. Thought it
might be the filter cap, removing it didn't change anything. Thought
there might be shorted lines on the edge connector, but there aren't
(except Vcc and RD5 as expected). The sockets are connected in parallel,
pin N on the left socket is connected to the same pin on the right socket.

At this point I'm wondering if maybe there's some kinda micro-fine crack
in a trace, so it reads connected with my cheap meter but acts like a
capacitor when it's in the Atari. In other words I'm grasping at straws...

October 21, 2019

I'm definitely not a photographer, but...

Front

Back

You can see the filter cap's no longer connected, I did that last night.

I checked all the pins on the card edge connector last night, no pin is
shorted to any other pin, except vcc and rd5 (board's made that way). Also
I checked all the pins on both sockets, the two sockets are in parallel:
pin X on one socket is connected to pin X on the other one.

Looks like the two ROMs have different part numbers because one of them
uses active-low chip select or output enable, and the other uses active
high. That way the top address line can be connected to both chips
without using an inverter or such.

I'm about out of ideas. Someone suggested using an eprom burner to
dump the roms, which I might be able to do, but the fact that the bare
board causes the Atari to crash means the roms aren't the problem (or,
not the only problem). Yet I can't find any shorted pins.

October 21, 2019

Not familiar with the story... was the released Gyruss game based on
this code, or was it a completely different implementation? Atarimania
doesn't list an author for the Gyruss that got released...

October 21, 2019

So I've got an old BASIC cartridge, CXL4002 with silver label. Had
it since maybe '87, and it used to work. Now it doesn't: Powering up
with the cart plugged in causes the Atari to come up in "green screen
of death" mode. No "pop" from the audio as I normally hear when the OS
clears the POKEY regs, and the Reset button doesn't do anything. It's
acting exactly the same as if I e.g. pulled the OS ROM or the RAM from
the motherboard. Cleaning the contacts didn't help. I tried the cart on
3 different (working) machines before I took it apart. The rest of my
testing (see below) was all done on an 800XL that has no problems I'm
aware of.

The inside of the cart looks fine, no dust/dirt, no burnt traces or
obvious bad solder joints, no visible cracks.

This cart's got 2 socketed masked ROMs (or maybe they're PROMs? no erase
window anyway). The part numbers are different: one is CO14502 and 8226,
the other is CO12402 and 8223CCP. I was honestly expecting EPROMs when
I took it apart: it came from a hardware hacker, had a hand-labelled
"Rev C" sticker on it.

I've been told by a couple of IRC users whose hardware knowledge is
greater than mine, that if I remove the ROMs and power up with the board
plugged in, the Atari should come up in self-test with only 40K of RAM
visible. Can anyone actually confirm this, from experience? (I have no
other socketed carts to try it with)

What actually happens when I remove the ROMs and plug in the board is
the same thing as with the ROMs in place: greenscreen, no pop, etc.

The only component on this board other than the ROM sockets is a little
filter capacitor that's wired between Vcc and ground. Someone recommended
I lift a leg of that, but it didn't make any difference.

Something else I tried: my other carts (which all work BTW) cause the
Atari to reboot when I insert them with the power on. So I tried it with
the bad BASIC cart, sitting at the self-test menu after booting with
Option held down. And it crashes the Atari with garbage like you get
from a bad display list. Pressing Reset after than causes the "green
screen of death", except the shade of green is the self-test screen's
background color (a bit brighter than the powerup greenscreen).

I'm thinking this is a really low-level problem: like, maybe a couple
of the address and/or data lines have shorted together. I don't have any
way to test the ROMs in a different cart board (my other carts all have
soldered in ROMs, no sockets), but I'm thinking the board itself is the
problem. Currently checking continuity between every pair of pins on the
cart's connector to see if any are shorted. Am I right in thinking that
shorted address/data pins could cause exactly the symptoms I'm seeing?
An open (unconnected) data or address pin shouldn't cause "instant death"
should it? (I mean the OS should still pop the speaker before it inits
the cart, right?)

Can anyone think of anything else I should check?

October 20, 2019

Any chance these can be made into an XEX file?

Rockball at least contains code that overwrites parts of itself if it's
run from RAM.

October 14, 2019

Not gonna touch the debate, but here's my take on using a 400:

If your main interest is games, there are lots of cartridge games that
work on a 400, without expanding the memory. Star Raiders for instance.
Also Defender, Pac-Man, Centipede, Super Breakout, Donkey Kong...

Some of the games do use the keyboard, but not heavily. The membrane is
fine for pressing the space bar to set off a smart bomb or H to engage
the hyperwarp engines...

If you're trying to learn BASIC, a 400 with the abovementioned $5 BASIC
cartridge might be a good starter kit... a lot of us started out that
way and the keyboard and lack of RAM didn't stop us from learning.

However, I can't recommend using a tape drive. Even when they're in
100% working order (and most aren't due to belt rot!), they're just too
slow. At some point you'll want a disk drive (real or otherwise) to save
your BASIC code... and that pretty much means you want at least 32K of
RAM, since the DOS loads from disk & takes up most of the memory in a 16K
machine. If you're having to upgrade the RAM anyway, might as well do 48K.

I had a 48K 400 for a few years (after getting rid of the original
16K 400 I started with). I enjoyed using it to play disk-based games,
but didn't do much typing on it: sitting next to it was an 800XL,
so I used that for coding and word processing and BBSing and such.
Would I have been happy with a 48K 400 as my only Atari? Hard to say,
but I definitely would have used it as much as I did the 800XL.

Of course the better solution for you if you decide you really need 48K
and don't want to do any mods/upgrades, would be to buy an 800. No idea
what they go for these days, maybe get the 400 for now and patiently
await an 800 at a price you can afford later?

I'd recommend an 800XL, but you've made it clear enough that you don't
like the XL or XE machines... too bad, because an 800XL makes the
best starter Atari IMO: built-in BASIC, 64K, decent keyboard, and the
!@%#$^@#%^ keyclick sound is routed to the regular audio output so you
can turn it down when it gets on your nerves (on 400/800, you have to
disassemble the machine and unplug the internal speaker, or install a
switch to turn the keyclick on/off).

About the TI-99: I won't say anything about whether or not you should
get one insted of an Atari (I'm biased, I've had an Atari for decades). I
will note that if you decide to add an original TI-made floppy drive to
a TI-99, you'll be giving up a good chunk of desk space. The peripheral
expansion box is huge and heavy (seems solidly built at least). Using
a cassette for storage on a TI is just as miserable as it is on Atari.

October 9, 2019

Ages ago I had a 400 that had problems with the cartridge port, it
turned out to be the little DOM sticker Atari put under the lid to the
cart port. Over time the adhesive lost its sticky, and it fell into the
cart port & blocked one or more of the pins.

If you shine a light in there and see the same thing, you can do what
I did: carefully remove the sticker with tweezers, then clean the cart
port by spraying QD or Deoxit [*] in there & inserting/removing a cart
repeatedly.

[*] BITD, I used Radio Shack Color TV Tuner Cleaner. But I doubt that's
still available.

October 3, 2019

Each country's got one or more DATA lines. First line has the country
name, capital name, and a list of plot/drawto X/Y coordinates expressed
as character data. The last pair is either 2 ctrl-A's (meaning "no more
data") or else 2 inverse zeroes (meaning there's another string of data
on the next line, I guess for countries with discontinous territory).

Also the very first data line, last number, is the total number of
countries. If you were just unifying the former East/West Germanies,
you'd decrease it by one.

For countries that have changed names and/or capitals, but kept the
same borders, you just change the name/capital data. For countries that
merged or split or otherwise changed shape, you gotta draw out the shape
and encode it as ATASCII byte pairs (fiddly work).

October 3, 2019

"Just" data statements... now that I look at it in BASIC instead of a
hex editor, I can see what you mean, ATASCII gibberish. The code that
interprets it is pretty short though.

October 3, 2019

Looks like DATA statements in a tokenized BASIC program. Possibly
you can just CLOAD it, edit, and resave? (Or maybe not, it may be
"list-protected").

September 27, 2019

Honestly I wonder how common it is for the Ingot PS to fail? Or is it just a rampant 3 decade rumor?

The only failed Atari power supply I ever had, was an ingot... which was
dead when I got it (in like 1988), and had failed in such a way that it
was putting out -2 volts (like, 2 volts with backwards polarity from
what it's supposed to have). So I'm one of the 3 decade rumor-mongers
I guess... the good news was, the -2V didn't actually damage the 800XL
it came with.

September 22, 2019

Might just need to clean the SIO cables & port. Get a can of Deoxit
or QD electronics cleaner, spray into all the holes in the ends of all
your SIO cables. After spraying each one plug/unplug it in the SIO port
a few times.

If that doesn't help, try replacing the SIO cables, if you can find any
on ebay or whatever.

The tape you tried to CSAVE to, what happens if you listen to it on a
regular audio tape player? You should hear the squeals and jangly data
blocks, if it actually recorded anything.

It's possible you have a bad POKEY, but the machine boots and you
can hear audio during the audio/visual part of the self-test, and the
keyboard works, right? So the POKEY is at least somewhat working. A
replacement is pretty easy to get, worth a try, if cleaning the cables &
port doesn't help.

September 9, 2019

DB-9 gender changers can be had for next to nothing, if someone's really
determined to use the wrong cable...

August 30, 2019

Small solder blob across two pins, takes 5 seconds, and the removal is also a 5 second non destructive deal.

Hm, been a while since I looked, but aren't the pins close enough together
that you could just use a jumper from e.g. an old IDE hard drive?

I can understand why the OP doesn't want to do this though. The cart door
acting as a power switch was a feature. I remember swapping game carts
and never having to touch the main power switch... very early form of
"plug & play" I guess.

August 29, 2019

There's 2 types of CR/LF mangling that can occur. The "error 137" files
have all the $0D bytes removed, and I've found a few in the Holmes
archive that have an extra $0D after every $0A in the file.

Recovering the second type might be possible, since tokenised BASIC has a
well-documented format with some internal redundancy: line length bytes,
plus statement length, plus the fact that the line numbers will always
be in ascending order, etc. All the information is there in the file,
a recovery tool would just have to figure out which $0D bytes are extras.

Recovering the first type might be possible, with a brute force
algorithm. Just find the spots where the token structure breaks, and
start inserting/removing $0D bytes at every position until you get
something that makes sense...

How do these broken files end up preserved in archives like Holmes or
TOSEC anyway? Nobody bothers to check & see if they even run, before
adding them to the archive to be preserved for all time?

August 15, 2019

BXL will bomb at the Ready prompt and not accept any input without the chip installed

Plain BASIC will fail too.

returns valid output for Sin(X)

Fun trivia: the code for SIN() actually lives inside the BASIC (or BXL)
cart. Though it does call several of the OS FP routines, so it's still
a good test.

August 14, 2019

I truly believe that pirating started because of the greed of software
and hardware companies.

Speaking as someone who had an Atari before he was old enough to get
a job... For me it wouldn't have mattered, at age 11-12, whether a
game was $5, $50, or $500. Parents weren't rich and I had no way of
getting my own income (paper routees were never a thing where I grew up,
cutting lawns might have worked but competition from the other kids was
fierce). So even the cheapest software was out of my reach. There were
a lot of kids like me...

August 13, 2019

Could imagine having 4 or 5 800s, one with CTIA + OS rev A, one with GTIA
+ OS B, and the rest with various upgrades. Since I've only got one 800
(GTIA + OS B), I wouldn't put a CTIA in it... or any upgrades either
(modern or old-school).

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