CPU (LSI14: HD6433294A33F)
The 16-bit CPU contains a 32k-bit ROM, a 1k-bit RAM, seven 8-bit I/O ports, an A/D convertor and MIDI
interfaces. The CPU gains access to the working storage RAM, the DSP and the key controller. The CPU
interprets MIDI message using the working storage RAM. The CPU also controls buttons and LEDs.
The following table shows the pin functions of LSI14.
Pin No.TerminalIn/OutFunction
1P50/TXDOutMIDI signal output
2P51/RXDInMIDI signal input
3P52/SCKOutReset signal output
4-RESETInReset signal input
5-NMIInPower ON trigger signal input
6VCCIn+5 V source
7-STBYInStandby signal input. Connected to +5 V.
8VSSInGround (0 V) source
9, 10XTAL, EXTALIn16 MHz clock input
11, 12MD1, MD0InMode selection input
13AVSSInGround (0 V) source
14P70InAnalog input terminal for the pitch bend wheel
15 ~ 21P71 ~ P77OutInpuminals from keys (KI1 ~ KI7)t ter
22AVCCIn+5 V source
23 ~ 30P60 ~ P67OutLED drive signal output
31VCCIn+5 V source
32 ~ 48A0 ~ A15OutAddress bus
40VSSInGround (0 V) source
49 ~ 56D0 ~ D7In/Out Data bus
57P40OutKO signal data
58P41OutClock for KO signal generator
59P42OutAPO signal output
60P43OutRead enable signal output
61P44InWrite enable signal output
62P45NNot used
63P46Out16 MHz clock output
64P47NNot used. Connected to +5 V source.
DIGITAL SIGNAL PROCESSOR (LSI11: HG51B155FD-1)
Upon receipt of note numbers and their velocities, the DSP reads sound and velocity data from the sound
source ROM in accordance with the selected tone; the DSP can read rhythm data simultaneously when a
rhythm pattern is selected. Then it provides 16-bit serial signal containing data of the melody, chord,
bass, and percussion to the DAC. When an effect is selected, the DSP adds the effect to the sound data
using a 256k-bit RAM.
The following table shows the pin functions of LSI11.
N 7 N |
ACEC
