Input/Output - 5200 joystick ports

[flickertail]

I have question about how I/O is handled on the 5200 joystick ports in comparison to the 2600/7800.

 

On the 2600 the 1-4 pins on each joystick port can be set to output by setting the appropriate bit in the SWCANT register to '1'. And then I/O is handled by setting the appropriate bit for each pin to either 1 or 0 in the SWCHA register.

 

Does it work in a similar manner for 5200 programming? If so, which pins on the port are used for I/O output?

 

I ask because I am developing at BT/USB adapter for the 2600/5200/7800 consoles. Here is test of the adapter prototype in action on the 5200.

 

[Rybags]

I don't think so.  5200 has no PIA so that rules out the digital outputs it provides.

 

Stick axes are analog by means of 2 paddle (pot) inputs per port.  Keypads are by means of the Pokey keyboard scanning.

And fairly sure there's a fire button connected to GTIA STRIG input per stick.

 

I seem to recall a method being described that uses fast pot scan mode to be able to do digital output on a pot line but unsure how and if it can be done on the 5200.

 

A better solution for what you describe for the 5200 would probably need D->A converters to provide the variable stick X/Y values.

Keys... you'd probably need to monitor the keyscan and return relevant outputs at the right times.

[flickertail]

2 hours ago, Rybags said:

I don't think so.  5200 has no PIA so that rules out the digital outputs it provides.

Rybags - Thanks for the info.

 

What I’m hearing is that there is no official way of doing it like there is on the 2600/7800. Which I am also guessing means that there is no real for it either.

 

This works out for the best for us anyway. Less to implement.

 

Unless I misunderstood your post.

 

Thanks!

-A

[+DrVenkman]

EDIT: I misunderstood what you were asking. Yeah, Rybags nailed it. There's no O in the 5200 controller ports, only I.