This is a board for the SPO256 chip used in several Atari speech projects in the 1980's

For an Atari 800xl it will fit in the 2 joystick ports, but other Ataris may need extension cables.

There are several articles on the construction and software.

The original article:

Analog Computing 29, April 1985 vol 4 page 59

With follow up articles and others using the same hardware:

Analog Computing 32, July 1985 vol 7 page 7 (Correction)

Analog Computing 34, September 1985 vol 9 page 94 (Correction)

Analog Computing 56, July 1987 vol 7 page 54 (Talker by Anthony Nogas)

Antic, January1987 vol 5 n 9 p13 (Talking Typewriter by Bill Marquardt)

Atari Classics, April 1993 vol2 n 2 page 19 (Cheep Talk Type 'n' Talk by Louis Marcotte)

See more here:

https://atariage.com/forums/topic/314966-finally-built-a-cheeptalk/?tab=comments#comment-4706231