st2064b Sitronix Technology Corporation, st2064b Datasheet - Page 25

• Manufacturer Part Number: st2064b
• Description: 8 Bit Microcontroller With 64k Bytes Rom
• Manufacturer: Sitronix Technology Corporation

1
13.1 Function description
The built-in dual channel Programmable Sound Generator
(PSG) is controlled by registers. Its flexibility makes it useful in
applications such as music synthesis, sound effects generation,
audible alarms and tone signaling. In order to generate sound
effects while allowing the processor to perform other tasks, the
PSG can continue to produce sound after the initial commands
have been given by the CPU. The structure of PSG was shown
in FIGURE 13-2 and the PSG clock source is shown in
PS: In order to make sure the PSG function is working normally on the EV or Real Chip Board,
Ver. 3.0
1
3
3
.
.
Please connect PSG‘ s power PVCC to VCC
P
P
S
S
DACE
From DAC Generator
VOL[1~0]
PSGC[3]
G
PSGC[2]
G
DACE
DACE
C1out
PSGC[6~4]
OSCX
BDB
BD
RC
Preload Data Before First Count
CH1
Vol_CH1
MIXER
IN0
IN1
Output
PSG Selector
C1TEN
C1NEN
Select
FIGURE 13-1 PSG Clock Source Control
FIGURE 13-2 PSG Block Diagram
Output
Channel 1 Tone
Channel 1 Noise
Enable
LOAD
Enable Output
IN0
IN1
IN0
IN1
25/57
MUX2
PSGCK
SEL
MUX2
Output
SEL
OUTPUT
OUTPUT
FIGURE 13-1. ST2064B has three playing modes. First is that
both channel0 (CH0) and channel1 (CH1) output square type
tones. Second is CH0 outputs square tone, and CH1 outputs
noise. Third mode is PWM DAC mode. Sounds of two channels
are mixed into one signal and are outputted in the form of
digital waveform from two pins, PSGOB/PSGO. Therefore one
AC waveform can be performed.
C1Tone
C1Noise
B6 B5 B4
PSGOB
X
X
0
0
1
PSGO
IN0
IN1
PSGC
MUX2
SEL
OUTPUT
0
0
1
1
0
0
1
0
1
0
C1out
SYSCK x 2
SYSCK/2
SYSCK/4
SYSCK
SYSCK/8
PSGCK
ST2064B
5/8/09