SNC678
4-Channel Speech Controller
5.6 Auto Repetition
Auto repetition function helps SNC678 realize a “looping” sound automatically by
hardware without any software effort. Auto repetition function is a very useful
mechanism to implement “Sustain” sound in instrument synthesis. All 4 channels are
equipped with this function. Arbitrary lengths of looping sound are accepted by
SNC678.
5.7 I/O Ports
P1 to P6 are six 4-bit I/O ports. Any bit of each I/O port can be programmed to be input
or output individually. Any valid data transition (H L or L H) of each I/O port can
reactivate the chip when it is in power-down stage.
Port Data
PAD
Port Status
Weak
To Internal Data Bus
Read Control
I/O Port Configuration
Note: weak N-MOS’s can serve as pull-low resistors.
Ver: 1.3
6
June 8, 2005
SONIX [ SONIX TECHNOLOGY COMPANY ]
