Toshiba TLCS-900/L1 Series Manual page 215

3.14 Melody/Alarm Generator (MLD)
TMP91C824 incorporates melody function and alarm function, both of which are output
from the MLDALM pin. 5 kinds of fixed cycle interrupts are generated by the 15-bit free-run
counter, which is used for alarm generator.
Features are as follows.
•
Melody generator
The melody function generates signals of any frequency (4 Hz to 5461 Hz) based on low-
speed clock (32.768 kHz) and outputs several signals from the MLDALM pin.
By connecting a loud speaker outside, melody tone can sound easily.
• Alarm generator
The alarm function generates 8 kinds of alarm waveform having a modulation frequency
(4096 Hz) determined by the low-speed clock (32.768 kHz). And this waveform is able to invert
by setting a value to a register.
By connecting a loud speaker outside, alarm tone can sound easily.
And also 5 kinds of fixed cycle (1 Hz, 2 Hz, 64 Hz, 512 Hz and 8192 Hz) interrupts are
generated by the free-run counter which is used for alarm generator.
This section is constituted as follows.
3.14.1 Block Diagram
3.14.2 Control Registers
3.14.3 Operational Description
(1) Melody generator
(2) Alarm generator
91C824-213
TMP91C824
2008-02-20