Software Automatic Mouth (SAM)
Originally from http://simulationcorner.net/index.php?page=sam
What is SAM?
Sam is a very small Text-To-Speech (TTS) program written in C, that runs on most popular platforms. It is an adaption to C of the speech software SAM (Software Automatic Mouth) for the Commodore C64 published in the year 1982 by Don’t Ask Software (now SoftVoice, Inc.). It includes a Text-To-Phoneme converter called reciter and a Phoneme-To-Speech routine for the final output. It is so small that it will work also on embedded computers. On my computer it takes less than 39KB (much smaller on embedded devices as the executable-overhead is not necessary) of disk space and is a fully stand alone program.
SAM Github project (C source)