SM1350 series

NIPPON PRECISION CIRCUITS—13

One-shot mode repeat function

In one-shot melody mode, the output repeats the

same melody while STN is LOW. When STN goes

HIGH, the output continues until the end of the

currently playing melody and then stops.

One-shot mode perpetual repeat function

If the score ROM end code is set to the jump code,

the melody will continue to play continuously once

one-shot mode starts.

STOP pin

One-shot output mode stops when STOP goes from

HIGH to LOW. The STOP input is ignored in level

hold output mode and is also ignored in one-shot

mode when STN is LOW. Note that even when

STOP is LOW, STN has higher priority.

CT pin

A pulse in sync with selected notes or rests is output

on CT. There are 2 modes for the output pulses—

pulse mode and hold mode.

Pulse mode

In pulse mode, a 16.4 ms pulse is output when a note

or rest occurs for which the corresponding CT data

in score ROM is set to 1.

Hold mode

In hold mode, the output pulse inverts when a note or

rest occurs for which the corresponding CT data in

score ROM is set to 1. The output goes LOW after

the start of a melody and when jumping to the

leading note of a melody.

Note: Refer to the "TIMING DIAGRAMS" section to confirm melody timing specifics

Figure 12. One-shot melody repeat timing

STN

Melody

Output

#N

#N

#N

Figure 13. CT pulse mode output

CT DATA

CT

1

0

11

1

0

16.4msec

Figure 14. CT hold mode output

CT DATA

CT

1

0

1

1

1

0