SNC88085
24-Channel MIDI/Speech Controller
================== CONTENTS =================
1
2
3
4
5
5.1.
5.2.
5.3.
5.4.
5.5.
5.6.
5.7.
5.8.
5.9.
5.10.
5.11.
6
7
8
INTRODUCTION......................................................................................................................... 3
FEATURES ...................................................................................................................................3
PIN ASSIGNMENT ...................................................................................................................... 4
BLOCK DIAGRAM ..................................................................................................................... 5
FUNCTION DESCRIPTION....................................................................................................... 5
O
SCILLATOR
................................................................................................................................ 5
ROM........................................................................................................................................... 6
RAM........................................................................................................................................... 6
P
OWER
D
OWN
M
ODE
.................................................................................................................. 6
IR F
UNCTION
............................................................................................................................... 7
I/O P
ORTS
...................................................................................................................................7
S
AMPLING
R
ATE
C
OUNTERS
........................................................................................................ 8
A
UTO
R
EPETITION
....................................................................................................................... 8
V
OICE
S
YNTHESIZER
................................................................................................................... 8
M
USIC
S
YNTHESIZER
................................................................................................................... 8
DAC ........................................................................................................................................... 9
APPLICATION CIRCUIT......................................................................................................... 10
ABSOLUTE MAXIMUM RATING.......................................................................................... 13
ELECTRICAL CHARACTERISTICS ..................................................................................... 13
Ver: 1.5
1
Sep 08, 2006
SNC88085
24-Channel MIDI/Speech Controller
AMENDENT HISTORY
Version Date
Ver 1.0
Ver 1.1
Ver 1.2
October 07, 2004
November 12, 2004
March 21, 2005
Description
First issue
Modify Application Circuit.
1. Oscillator R-Type is “no connect”. Page5
2. Modify Application Circuit.(Low CLK Mode, 32768,
R-Type, Xin and Xout no connect) Page10
3. Modify Electric Characteristic (Max->Typical) Page12
4. Modify I/O Circuit in Page7
Ver1.3
June 30,2005
1. Modify Application circuit in Low CLK(RC mode)
R=91K, C=200pF
2. In Application Circuit add R=100 (direct key) in Page9
Ver1.4
November 18,2005
1. Modify Application Circuit add a diode between
“VDD“ and “VDDVR” @4.5V.
2. Modify Application Circuit add R=100 in each input pin
(direct key).
Ver1.5
September,8,2006
1. Removed Application circuit R=100 in each input pin
(direct key)
Ver: 1.5
2
Sep 08, 2006
SNC88085
24-Channel MIDI/Speech Controller
1 INTRODUCTION
The SNC88085 is a single chip 24-channel MIDI compatible wave-table/voice
synthesizer. Equipped with a powerful 8-bit controller and 24 I/O pins, it provides a
low-cost MIDI sound system solution. It’ low power consumption and operating range
s
makes it ideal for all battery operated devices using MIDI or voice synthesis.
2 FEATURES
Single Power Supply 2.4V – 5.5V
Powerful Built-in 8-bit Controller
Three 8-bit I/O ports
640*8 bits RAM
Maximum 64k program ROM
256K*12 shared ROM for program and voice data
Readable ROM code data
24-voice Polyphony through a high-quality speech synthesizer
Mark Event Supported in both Wave and Melody.
Individual adaptive playing speed from 4k-64kHz for all 24 channels
Automatic repetition for each channel
Volume modulation controlled by embedded multiplier
Two digital mixers with saturation control
Two built-in 10-bit current mode DA converters
Analog
Direct Drive speaker circuit.
System clock: 16.384M Hz (RC-type or Crystal Option)
1 MIPS CPU power free to user
Low Voltage Reset
Ver: 1.5
3
Sep 08, 2006
SNC88085
24-Channel MIDI/Speech Controller
3 PIN ASSIGNMENT
Symbol
P00 ~ P07
P10 ~ P17
P20 ~ P27
VDDVR
GNDVR
VDDPP
GNDPP
CVDD
VDD
GND
REGOUT
RST
XIN
XOUT
LXIN
LXOUT
CKSEL
TestM
VO1
VO2
BN0
BP0
I/O
I/O
I/O
I/O
P
P
P
P
P
P
P
P
I
I
O
I
O
I
I
O
O
O
O
Function Description
Bit7 ~ Bit0 of I/O port 0
Bit7 ~ Bit0 of I/O port 1
Bit7 ~ Bit0 of I/O port 2
Positive power supply for ROSC
Negative power supply for ROSC
Positive power supply for Direct Drive
Negative power supply for Direct Drive
Positive power supply for internal circuit
Positive power supply for I/O
Negative power supply
3V regulator output
Chip Reset (Active low)
High clock Crystal In
High clock Crystal Out
Low clock Crystal In
Low clock Crystal Out
Clock type select
‘
VDD’ RC oscillator
‘
GND’Crystal
Test Pin
DA1 output
DA2 output
Direct Drive negative output
Direct Drive positive output
Ver: 1.5
4
Sep 08, 2006
SNC88085
24-Channel MIDI/Speech Controller
4 Block Diagram
ROM
Program/Speech/Melody/Instrument waveform
256K
12
bits
Address Pointers/ STACK
Timing
Generator
OSC
Music
Synthesizer
IO0
SRAM (640 bytes)
Timer
ALU
10bit D/A X 2
Direct Drive
IO2
Sampling
Rate Counter
Voice
Synthesizer
IO1
5 FUNCTION DESCRIPTION
5.1. Oscillator
CKSEL (Clock Select) input pin of the SNC88085 selects between crystal
oscillator/ceramic resonator or RC type oscillators as system clock.
VDD
20pf
CKS E L
XIN
XO UT
CKS EL
XIN
XO UT
20pf
NC
NC
16.384Mhz
G ND
Crys ta l / Re s ona tor
RC Os cilla tor
Notice: For RC Oscillator, Keep XOUT and XIN as “No Connect”.
Ver: 1.5
5
Sep 08, 2006
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