SNC111

One Channel Direct Drive Speech Controller

5 FUNCTION DESCRIPTIONS

5.1. Oscillator

SNC111 accepts RC type oscillator for system clock. The typical circuit diagram for

oscillator is listed as follows.

OSC

VCC

RC Oscillator

5.2. ROM

SNC111 contains substantial 32K word (10-bit) internal ROM. Program and voices

are shared with this same 32K word ROM.

5.3. RAM

SNC111 contains 64 nibble RAM. The 64 nibble RAM is divided into four pages (page

0 to page 3, 16 nibble RAM on each page). In our programming structure, users can

easily define and locate RAM page in the program. For instance, users can use the

instructions, PAGEn (n=0 to 3) to switch and indicate the RAM page. Besides, users

can use direct mode, M0 ~ M15 in the data transfer type instructions, to access all 16

nibbles of each page.

5.4. Power Down Mode

“End” instruction will power down SNC111 and enable IC to consume fewer current for

power saving. (<3uA @VDD=3V and <5uA @VDD=5V) Please be aware that when

the power down mode is activated in SNC111, any valid data transition (L H or H L)

occurring on any IO ports (P2 and P3) will lead SNC111 back to normal operation

mode.

5.5. Sampling Rate Counter

The unique sampling rate counter is designed in voice channel to be able to play

diverse voices at different sample playing rates. The playing rate can be adaptively

set up among from the wide ranges of 2.5KHz to 20KHz. This feature makes voice

close to its original source and yield the better voice quality.

Ver: 1.3

June 8, 2005

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