The DoubleTalk Chipset is a speech synthesizer designed for use in talking devices accessible to individuals who are blind or have low vision, or in speaking aids for individuals with speech disabilities. Applications include talking optical character recognition systems, ATM machines, talking pagers and PDAs, GPS navigation systems, vending and ticketing machines, dial-up information systems, handheld barcode readers, security systems, and aids for individuals with speech or visual disabilities. These speech synthesizers convert plain English text into speech automatically, with programmable voice parameters, such as voice, pitch, rate, volume, tone, expression, articulation, etc. Other features include on-demand playback of up to 33 minutes of recorded messages and sound effects; non-volatile storage of user settings, dictionary, and greeting message; musical and sinusoidal tone generators; DTMF (touch-tone) dialer; stop, pause and resume controls; analog and digital audio outputs; four-channel, 8-bit A/D converter for battery monitoring, data acquisition, etc. Model RC8660 also includes an integrated voice/sound/data recorder.