Some notes on programing for the Disney Sound Source.

 The Sound Source is a simple digital-to-analog sound device for the IBM PC
type computers. It consists of two parts, a dongel that hang off the printer
port and a 9 volt battery amplifier/speaker box.

 Since the SS is an output only device, I have to assume that you have a
source of digital sounds to play back. Due to filtering on the SS, it works
best with sounds sampled at less than 8Khz. This limits the sound output to
around 4Khz, about as good as a very good phone connection.

 While Disney has been less than forthcoming about information about a
software developers kit, writing sound output routines for the SS is fairly
simple.

 You only have to be concerned with 3 routines.

1. SS on.
2. Write data to SS.
3. SS off.

 The output rate is controlled by your program, usually by the hardware
timer.


 To turn on the SS do the following:

Read PrinterPort + 2     ;ControlPort
Clear Bit 3
Write ControlPort

In ASM:

SS_ON:
        MOV     DX,37Ah         ;Address of LPT1 control port
        IN      AL,DX
        AND     AL,11110111b    ;Clear bit 3
        OUT     DX,AL           ;Turn on SS


 Turning the SS off is almost the same:

Read ControlPort
Set Bit 3
Write ControlPort


SS_OFF:
        MOV     DX,37Ah
        IN      AL,DX
        OR      AL,00001000b    ;Set bit 3
        OUT     DX,AL


Send data like this:

Write data to PrinterPort
Pulse Bit 3 of ControlPort

BYTE_OUT assumes AL has the data byte to be sent to the SS and that
the SS is on. (Bit 3 of ControlPort is off)

BYTE_OUT:
        MOV     DX,378h         ;PrinterPort
        OUT     DX,AL           ;Send data to SS
PULSE:
        ADD     DX,2            ;Set DX to ControlPort
        IN      AL,DX
        OR      AL,00001000b    ;Bit 3 on
        OUT     DX,AL
        JMP     $+2             ;short delay to settle buss
        IN      AL,DX
        AND     AL,11110111b    ;Bit 3 off
        OUT     DX,AL


 I know that these routines are fairly simple and the could be improved on.
A close examination of the SS electronics reveals the capacity to generate
interrupts, (set bits 2 and 4 of ControlPort to possibily enable ints)
but I haven't gotten that far yet.
 If you have any comments, critiques, ect. I am:

Mark Phillips
Cserve 73167,3216

 Shameless Plug Time.

 Many thanks to Adrienne Cousins of VersaWare for her help with the above.
Get, register, and enjoy Adrienne's SPUTTER Sound System. It handles
Adlib, SoundBlaster, all Covox sound products, Disney SS, and the PC speaker.
Easy to use and fun, it's the best !!!

Search for SPUT115A, B, and C on your local BBS.

mjp









