Re: [hatari-devel] behaviour when RS232 is not emulated

[Thomas Huth <th.huth@xxxxxx>]

Am Mon, 05 Dec 2011 00:39:06 +0100
schrieb Nicolas Pomarède <npomarede@xxxxxxxxxxxx>:

> Hello
> 
> some games ('Treasure Trap' and 'The Deep' for example) are writing 
> messages or debug informations to the rs232 port. Those are not
> required to play the game, but the program will loop until it can
> successfully send the bytes.

Right, I've once seen this behaviour, too, in the game "Running Man".
At that point in time, Hatari was not good enough to run the rest of
the game, so I never really tried to fix the rs232 problem for this
game...

> In the case where rs232 is not enabled, we do :
> 
> void RS232_TSR_ReadByte(void)
> {
>          if (ConfigureParams.RS232.bEnableRS232)
>                  IoMem[0xfffa2d] |= 0x80;        /* Buffer empty */
>          else
>                  IoMem[0xfffa2d] &= ~0x80;       /* Buffer not empty
> */ }
> 
> I think it would be better do always "|= 0x80" to report an empty
> buffer (which is more or less the case when rs232 is disabled).
> 
> This way, programs will consider bytes are always sent and games that 
> don't require send/receive capabilities will still work without
> enabling rs232.
> 
> As I didn't write this part, does someone have any objection on this, 
> any side effect I don't know ?

Sounds fine for me, I don't think that this will cause any other
trouble instead.

 Thomas