Arcade Adapter for Mac*Man

[Mu0n]

This little thing connected to the DB9 mouse port of pre-ADB Macs:

 

 

 

and allowed you to play Mac Man using an Atari Joystick.

 

I just tried plugging my custom gamepad and running the game, but it will show that it doesn't recognize its adapter. Perhaps the normally unused pin of the DB9 connector is set high with this adapter by linking it to the 5V pin? It's hard to say without having access to the interior of that casing (I don't own such an adapter).

 

 

I also found a reference to that game and adapter in a MacUser August edition of 1987

 

Edited July 19, 2020 by Mu0n

[Crutch]

Wow, I’d forgotten all about that thing. I had one circa 1987. Couldn’t tell you how it worked, though, I’m afraid ... I do recall that Mac Man was not a great game!

[Mu0n]

do you know what would happen if I just use a jump wire inside the Mac Plus case between pin 2 and 6? Smoke? Is it possible for the Mac to probe pin 6 for special checkups?

[sfiera]

The Mac Plus schematic indicates that pin 6 is not connected at all. Here’s a thought—what happens if you plug in a regular mouse and hold down the button when launching the game? It could be as simple as Mac•Man checking for the mouse button being held down (pin 7 being grounded), on the assumption that players wouldn’t do that while opening the game.

[Crutch]

If that doesn’t work - We could figure out what it’s doing by launching Mac Man and dropping into the debugger to see what it’s checking before popping this error. 

[Mu0n]

I'll try those ideas! This is so freaking hard to search for that derelict item either on eBay or just the web. 

[Mu0n]

Right after double clicking to launch the game, I tried a 3rd, held click, but it seemed to have no effect. There are several spots where it might do some kind of check. Before the splash screen, during it, after it. after selecting PLAYER 1 from the menu (that's when it tells you it can't detect a joystick and shows you the keyboard control layout). 

 

[NJRoadfan]

Best bet is above, dissembling the game's detection routines. Annoying, but doable. Being that you can't send data out the mouse port, it can't be too complicated.

[napabar]

On 7/23/2020 at 6:45 AM, NJRoadfan said:

ion routines. Annoying, but doable. Bei

What kind of custom controller is it?  Just having the Atari plug doesn't mean Atari compatible.  Systems like the Genesis and the Vertex have the same plug, but are electrically different.  Easiest solution is to get an Atari 2600 joystick and try it out.

[olePigeon]

@napabar  @Mu0n The linked article says "Atari compatible joystick."  So I would test it with an Atari joystick.

[Mu0n]

Again, I don't have the adapter, that image was taken off the net.

 

[napabar]

On 2/19/2021 at 9:51 AM, Mu0n said:

Again, I don't have the adapter, that image was taken off the net.

 

If you don't have the adapter, what were you plugging your custom controller into???

[sfiera]

Here's another dumb idea…

 

If the adapter hooks up the Atari wires to the mouse wires in the “obvious” way, then I think the joystick would act like a mouse that can't move more than 1px from its origin. So, what happens if you start the game with the cursor in the upper-left hand corner?

[SuperSVGA]

On 3/7/2021 at 3:02 AM, sfiera said:

Here's another dumb idea…

 

If the adapter hooks up the Atari wires to the mouse wires in the “obvious” way, then I think the joystick would act like a mouse that can't move more than 1px from its origin. So, what happens if you start the game with the cursor in the upper-left hand corner?

Mouse input should be relative, not absolute. I believe the mouse typically provides X direction, X speed, Y direction, and Y speed as input. 
The Atari controller however provides each direction more like a button, so one for each of the four directions. 

[sfiera]

That’s true of more modern mice, like ADB and PS/2, but an M0100 mouse exposes raw quadrature signals. Each axis has two pins that cycle 00 → 01 → 11 → 10 in forward or reverse order depending on the direction. An Atari controller wouldn’t ground opposite pins at the same time, so if you wired the Atari axes to the Mac axes, the cursor should never go more than 1px forward or back from 11.

[cheesestraws]

But those signals are integrated over time; there's no way for a quadrature mouse to say to the host 'move to the origin'.  So I'm not sure that that would be anything other than a very error-prone signal for the kit to give.

 

But yes, you're right about only moving 1px at a time.  I had to think about it for a moment, but yeah; pressing down a button would move you one step along the quadrature waveforms then releasing would essentially move you back.

[Mu0n]

On 3/7/2021 at 4:45 AM, napabar said:

If you don't have the adapter, what were you plugging your custom controller into???

 

Into the 9 pin connector for the mouse. It's my own arduino based gamepad I made with a 3d printed casing, inspired by this thread.