rfc Adding a UDP streaming mode for fast action games

[tschak909]

Generalizing MidiMaze Mode

There seems to be a viable reason to have a streaming mode for arcade games that can't be pausing to deal with SIOV traffic. 

 

The solution would be to provide a mode which opens a UDP socket, and sends/receives packets there in a streaming fashion. Asserting COMMAND would quit this mode.

the Midimaze mode can be generalized for this, basically by:

* Adding a Midimaze start ($F0) command to fuji device, that has: Aux1 = desired POKEY divisor, payload is "hostname:port" 0 = 127014 max
* extending the mididev to allow for baud rate to be specified.

 

so midimaze continues to work as it has been.

 

and if you send a cmd $F0, it will set whatever baud rate you wish, and establish UDP socket. 

 

This is literally the "high performance" option for arcade games that simply would not have any other viable choice (such as 8-bit slicks). 

 

I am reticent to implement this, because I have a feeling it will be abused by everybody writing games, even those that don't need it.

thoughts?

[Kyle22]

Do it. Let's see what happens.

 

[_The Doctor__]

never fear giving a high performance option, sometimes you have to put the peddle to the metal !

[+DjayBee]

13 hours ago, tschak909 said:

I am reticent to implement this, because I have a feeling it will be abused by everybody writing games, even those that don't need it.

Implement it in a way that nothing else can be done over the Fujinet while this channel is open.

 

1 hour ago, _The Doctor__ said:

sometimes you have to put the peddle to the metal !

Poor Chuck - R.I.P.

[cathrynm]

9 hours ago, DjayBee said:

Implement it in a way that nothing else can be done over the Fujinet while this channel is open.

 

What this sounds like. That this would be like Atari 850 with all the buffer overrun trickiness.

[tschak909]

53 minutes ago, cathrynm said:

What this sounds like. That this would be like Atari 850 with all the buffer overrun trickiness.

similar. but the ESP will queue packets.

-Thom

[cathrynm]

3 hours ago, tschak909 said:

similar. but the ESP will queue packets.

-Thom

Oh I see, does that mean it'll be able to, say, stop data coming into the Atari, do some other SIO commands, and then resume back where it left off without missing a byte?

[tschak909]

yes.

-Thom

 

[tschak909]

So basically, when it goes into stream mode, it takes over the entire SIO bus, and an input routine would need to be provided to read the data from the fujinet.

 

Of course, we have the PROCEED line to tell us when new data comes across.

 

Does somebody want to put together a set of asm routines that:

 

(1) Initializes the pokey to the appropriate baud rate (divisor), and installs:

(2) a VPRCED interrupt routine to know when something is ready for receipt

(3) a SERIN interrupt routine to grab the resulting data

(4) a shutdown routine that puts everything back

 

while I work on the firmware side of things?

 

-Thom