13 Reset 81 Power Onoff Detection Circuit

When the power switch is turned on, terminal Ml receives a differential pulse which triggers CPU operation. By receiving signal K09 from KM KI4, or KI8 terminal, CPU descriminates the Mode switch position. Since VA stays at +5V even power switch is turned off or at the APO (Auto Power Off), the reset signal appears only when new batteries are set or an AC adaptor is inserted. The noise killer circuit eliminates negative portion of signal Ml at Power OFF. S-8053 is a voltage detector which...

14 Power Supply Circuit

The Power Supply Circuit consists of a voltage regulator and an APO (Auto Power Off) circuit. When power is ON and operation is normal, the APO signal from the CPU maintains HIGH level. Transistors T4 T9 turn on providing the voltages to the circuits. The signal APO becomes LOW, when the keyboard is not operated for seven minutes, and transistors T4 T9 turn off causing the voltages except VA to shut off. Voltages VA (5V) and VDD1 (ground) are always provided to the CPU even at APO. Transistors...

10 Peripheral Device Access

A(PD43256C-12L is a 256Kbit RAM for storing sampling sounds and ROM pack data. The data in RAM are kept even power switch OFF as long as DC7.5V is provided. iPD23C256EAC is a 256Kbit ROM and contains preset tone, percussion data, and system execution program. MSM6294-02 is a percussion generator and issues percussion sounds in accordance with the data from CPU. The chip select condition is as follows. H High level L Low level X Irrelevant

Pin Function of Percussion Generator

The terminal holds LOW level at power switch on for initializing the internal circuit The LSI reads the percussion data from the CPU when the terminal is LOW level. Chip select signal input.Fixed at LOW level. Ground (0V) source for internal digital circuit +5V source for internal digital circuit CPU outputs four each of pitch and envelope signals. Normally all the signals are for melody sounds however, when a ROM Pack music is played, each pitch and envelope signals become obbligato, bass,...

6 Cpu Msm628305gs

O Generates Pitch and Envelope signals for Melody, Chord, Bass and Obbligato sounds, o Controls Keys, Switches and peripheral devices. The following table is the pin functions of the CPU. 5V source for internal ADC (Analog to Digital Converter) Chip enable signal for memory devices. LOW active. Output enable signal for memory devices. LOW active. Write enable signal for RAM. LOW active. Write enable signal for Percussion generator. LOW active. ROM pack's chip select signal. LOW active. Ground...

Parts List

Prices and specifications are subject to change without prior notice. 2. As for spare parts order and supply, refer to the GUIDEBOOK for Spare Parts Supply, published separately. 3. The numbers in item column correspond to the same numbers in drawing. Unit Price N.R. Yen FOB JAPAN R-20-100-G-T24-T 1 5W, 100ohrn, 2 R-20-4.7K-G-T24-T 1 5W, 4.7Kohm, 2 R-20-10K-G-T24-T 1 5W, 10Kohm, 2 R-20-100-J-T24-T 1 5W, 100ohm, 5 R-20-560-J-T24-T 1 5W, 560ohm, 5 R-20-1K-J-T24-T 1 5W, 1 Kohm, 5 ft New...