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IMPORTANT NOTICE This manual has been provided for the use of authorized Yamaha Retailers and their service personnel. It has been assumed that basic service procedures inherent to the industry, and more specifically Yamaha Products, are already known and understood by the users, and have therefore not been restated.
CONTENTS The Disklavier Design Specifications Names and Functions • Front Panel • Remorte Control Unit • Connectors How to Format Disks MIDI Data Format MIDI Implementation Chart MIDI Troubleshooting and know-how Warning Displays and error messages Error number meaning Block Diagram Disassembly Procedure Adjustment Procedure •...
The Disklavier Design The Disklavier consists of a control unit and a drive unit comprising of a sensor unit, solenoid units, power source unit and I/O control unit. Specifications Design • Key switches Control unit Dot matrix (16 characters x 2 lines) •...
Names and Functions Power Switch Liquid Crystal Display (LCD) Pressing this switch turns power on, shown by The LCD displays a variety of information such the power indicator and the Volume button as the music title, adjustment values, the time that indicator lighting up.
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Rec. button Repeat buttons Pressing this button causes its indicator to light Operate these buttons when you desire repeated up, entering record stand-by mode. Recording can playback of certain pieces of music or sections now be started by pressing the Start/Pause button. within them.
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Part Cancel buttons Trans/Beat When you want to transpose (change) the key It is possible to cancel either the left-hand or of a piece of music for playback, press this button right-hand part by pressing the corresponding Part in stop mode, during playback or playback pause, Cancel button when playing back music recorded making sure that the button's indicator lights up.
Remote Control Unit Remote control signal window Start/Pause button Please operate the remote control while making Has the same functions as the Start/Pause sure that this infrared signal transmission window button on the front panel. is aimed at the corresponding reception window on the front panel.
Return-FF buttons Connectors These buttons are for fast forward and rewind. They can be operated in stop mode or during playback. Fast forward or rewind continues until the respective button is pressed again. Volume buttons These buttons adjust playback volume level. They can be operated in stop mode, during playback or playback pause.
How to Format Disks After inserting a disk, press the Rec. button while keeping the Stop button depressed. You can release these buttons when the display reads "FORMAT OK?". In answer to the above message, press the Start/Pause button. (If you should decide not to proceed with formatting, remove the disk instead.) Reconfirm the above question by again pressing the Start/Pause button.
MIDI Data Format Transmission Conditions Transmission Data • CHANNEL INFORMATION 1) CHANNEL VOICE MESSAGES Key On/Off Status 1 0 0 1 n n n n (9n) n = channel number (0~15) Note No. 0 k k k k k k k k = 21 (A ) ~108 (C ): Note 1...
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• SYSTEM INFORMATION 1) SYSTEM REALTIME MESSAGES Note 3: When the preferred data, including active sensing, has been transmitted, if data is not transmitted within an interval of approximately 80 milli seconds, the main clock is transmitted. * The system realtime messages Timing Clock, Start, Continue, and Stop can be transmitted only when the metronome function is ON.
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Reception Conditions Reception Data • CHANNEL INFORMATION 1) CHANNEL VOICE MESSAGES Key Off Status 1 0 0 0 n n n n (8n) n = channel number (0~15) 0 k k k k k k k Note No. k = 21 (A )~108 (C Velocity 0 v v v v v v v...
MIDI Troubleshooting and Know-how When MIDI Is connected, there are a few mistakes and problems that occur frequently. A sound source instrument has been connected to the MIDI OUT terminal, but no sound is produced by the external instrument. • Are you sure the MIDI cable is firmly connected between the MIDI OUT terminal of the Disklavier and the MIDI IN of the external instrument? •...
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Split, transposition functions do not work on the external instrument. • Is the MIDI OUT set to DELAY OUT? (If it is not set to KEYBOARD OUT, these functions will not operate.) • Does the transmission channel of the Disklavier match the reception channel of the external instrument? When playing ensemble music, the external instrument receives all parts.
Warning Displays and Error Messages This Disklavier will display warnings and error messages on its LCD when operation has been incorrect or other problems have arisen. Should this happen, please take the appropriate measures after having found out what the trouble is by referring to the table below. Please note that some of these problems are easy to mistake for malfunctions though they are actually very easy to solve by yourself.
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Error Number and Description in Details When error occurred, the error number will be indicated on the 7 segment LED with pushing the L and R buttons at a time.
Disassembly Procedure 1. Removing the Case Parts and Action When tuning: 1) Open and lock the Top Board. 2) Loosen the screws and securing fasteners on the inside of the left Side Board. (See Figure 1.) 3) Remove the Upper Front Board. 4) Remove the Fall Board.
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2. Removing the Electrical Unit: *lf necessary, cut the binding tie. * For connector numbers, refer to the circuit diagram. * Before removing each unit, be sure to disconnect the AC plig. Removing the Control Unit: 12) Remove the following screws shown in Figure 5: the four at (A), the six at (B), the one at (C) and Figure 5.
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Removing the Key Sensor Unit: 19) Remove the Keyboard. 20) Disconnect the three connectors to the unit (CN8, 9, 4). 21) Remove the six screws shown at (A) on Figure 8, and remove the unit. Figure 8. Removing the Key Drive Unit: 22) Remove the fourteen connectors of the I/O Circuit Board (CN8, CN10~22) and the connector of the power source unit (CN8).
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Removing the Pedal Sensor Unit: 28) Remove the connector of the Sensor Circuit Board (CN3). 29) Remove the screws shown in Figure 11, and take out the unit. Figure 11 . Removing the I/O and Sensor Circuit Boards: 30) Remove all of the connectors. 31) Remove the six screws of the Sensor circuit board and the seven screws of the I/O circuit board., and take out the two units.
Adjustment Procedure 1-1. Adjustment of the Key Drive Unit The key drive unit is mounted as shown in the figure below. • Adjustment-Front and Back Fit the unit against the front surface of the key back rail. • Adjustment-Right and Left Instal Keys 2, 50, and 87 (black keys), then align the key drive unit so that each solenoid is at the center of its corresponding key.
1-4. Adjustment of the Pedal Cushion Unit Adjustment of the pedal cushion unit is as folows. Cushion unit is too high···Pedal rebound noise can occur. Cushion unit is too low···Pedal may not disengage.
1-5. Adjustment Procedure for the Sensor Units 1) Settings When Adjusting the Sensors: • Connect MIDI OUT on the DISKLAVIER to MIDI IN on the external sound source and set individual each unit so that transmission and reception of signals is possible. •...
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3) Adjusting the Key Sensor Unit: Depress a white key making sure sound is being produced on the tone generation system. Slowly release the white key and adjust the height adjustment screws (4 locations). The sound source should stop at a height of 4.5±0.5mm (half of key depth) from normal key level. Sound stop timing is too fast···Loosen the screw (counterclockwise) Sound stop timing is too slow···Tighten the screw (clockwise) 4) Adjusting the Pedal Sensor Unit:...
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Operation Test of Each Unit Using The Test Disk [TEST 1] Minimum-pressure single-note scale of 1 to 88 keys. Tests whether the keys are played back when the minimum touch pressure is applied. If a note is not sounded (although the keyboard operates normally):...
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[TEST 2] Standard-pressure single-note scale of 1 to 88 keys. Tests the operation of the key solenoid unit (for noise, etc.). If noise is generated:...
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[TEST 3] Applies pressure onto 5 consecutive keys. Tests the sound generation while playing trills (check for noise, etc.) If sound generation is faulty: If noise is generated: See [TEST 2] [TEST 4] Turns ON the Damper Pedal/Soft Pedal five times for one second each time. Tests the efficacy of the Damper Pedal and Soft Pedal.
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[TEST 5] Turns ON the Damper Pedal ten times for one second each time. Tests the operation of the Damper Pedal (for noise, etc.) If noise is generated: [TEST 6] Demonstration performance. Comprehensively tests all units in the playback system. Re-confirms [TEST 1 ] through [TEST 5] .
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[TEST 7] Recording and playback test. Tests the operation of the units in the recording system (using a disk for recording). Records then plays back the scale of Keys 1 to 88, pedal ON/OFF, and so on. The location of the defect can be determined by the error symptom that occurs, as listed below. •...
Error Display LEDs on the I/O Board As shown in the figure below, the I/O board is mounted with LEDs that indicate abnormal operation in the driving system. If an error occurs, the pertinent LED lights up next, after the solenoid power supply is turned OFF, the other LEDs also gradually light up.
Adjusting the Trimmer The operating efficiency of the piano action and keyboard will vary slightly according to the piano model. Even if two pianos have the same model number, minute differences may occur due to humidity, adjustment procedures, and other factors. When a person plays the piano, she/he listens to the sound and feels the key touch, then plays while making the necessary compensations.
Test Program 1. STARTING/ENDING THE TEST PROGRAM Among the two ROMs used for piano player control, ROM B contains the test program. When you simultaneously hold down the L and R buttons while you turn ON the power, TEST mode is entered. Upon entering TEST mode, the ROM Version, Table Version, Trimmer Value, and Controller Type are displayed as shown below.
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4) Switch Test The 7-segment LEDs display the number corresponding to each switch. Foot Switch=40 5) RAM Test Write, Read, and Verify operations are conducted, then the result is displayed. ( O K ! ! / N G ! ! ) 6) ROM Test The checksum of ROM B is calculated, and the result is displayed.
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8) PIANO Test For the play back system, single keys are successively pressed during approximately 0.5 seconds from Key 1. After Key 88 is pressed, the Loud Pedal and Soft Pedal are operated, then the sequence returns to Key 1 and is repeated. During playback, the START/PAUSE, Fast Forward (1-Key Skip), and Fast Reverse can be used.
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* Example 1: "AA" was written to Address $1234, but "00" was read back. * Example 2: During the test, the Track No., Side, and Sector No. being tested are displayed at the lower row of the LCD. • If an error occurs, its description and location are alternately displayed. Error Description Display DISK NOT READY...
Explanation of Sensor System The sensors on the DISKLAVIER are as follows: • Key Sensor Unit···Optical Sensor···Detects key information. • Hammer Sensor Unit···Optical sensor···Detects key information. • Pedal Sensor Unit···Mechanical sensor···Detects pedal information. 1. Key Sensor Unit, Hammer Sensor Unit: The Key Sensor, Hammer Sensor Units include the following equipment: •...
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This sensor system is used to obtain the key information listed below: Detection contents Detection method Which key is (Key Assign)? OR of K and M1 (see Note 1) When is (Note On Timing)? How strong is (Touch Data)? Time from M1 to M2 (see Note 2) How long is (Note Off Timing)? AND for K and M1 (see Note 3) Note 1: OR···Time during which either key sensor K or hammer sensor M1 has its light blocked by the...
LSI Data Table YM5205 (PMAC: Memory Access Controller) 1. OVERVIEW The PMAC contains the CPU peripheral circuit in a 64-pin OIL LSI. It selects addresses in and refreshes the dynamic RAM and also makes communication between the dynamic RAM and the FDC possible in the DMA mode.
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2. CONSTITUENT PARTS The internal circuit in PMAC consists roughly of six parts: DRAM controller···Controls address switching, timing, and memory refreshing DMA controller···Controls DMA transfers between FDC and DRAM Timer control···Controls interrupts generated by the internal timer and external triggers Address decoder···Decodes the addresses from the CPU and generates the address decode signals FDC support circuit···Generates clock signals for FDC and carries out write data precompensation for the disks...
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MB8877 (FDC: Floppy Disk Controller) To enter data on a floppy disk, 8 bits of serial data that is sent from the computer, must be converted into the corresponding parallel data. To this, again, the clock pulses must be applied. When reading data from a disk, the same procedure must be repeated, but the reverse order.
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YM3802 MCS (MIDI Communication & Service Controller) LIST OF YM3802 TERMINAL YM3802 Pin assignment...
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YM2019 KAPP (Key Assigner for Piano Player) 1. OVERVIEW This LSI detects the operation being executed (keys, hammers and pedals) while a piano is being played. Its offers the features listed below: 1) Detects the ON/OFF timing of keys in eight octaves (96keys) and the hammer speed. (For up to 16 concurrently sounded notes.) 2) Detects the ON/OFF status of the damper and shift pedals.
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3. Block Diagram 3-1. Key Scanner Scanning is beginning from the C # note of Octave 0 to detect the status of the hammers within the octave for witch Pin K is "1" (the octave in which a key is being pressed). Key scanning is then stopped for 16µSec.
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3-2. Key Assignor and Level Counter The data from the Key Scanner is assigned to an empty channel among the 16 channels. The operation conforms to the table as shown below, depending to the status of Pins K, M1, and M2. Based on the conversion curve selected by Pins , the Level Counter accumulates in 48µSec.
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3-4. Memory The Memory records the data listed below: The key address (note and octave) and Level Counter value of a Key-On event. The Key address of a Key-Off event. The number (SP1 or SP2) of a special function (pedal). 3-5.
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Description of the Data DO D1 D2 D3 D4 D5 D6 D7 Data Name EV="1" when an event has occurred. INDEX ————INDEX——————0 1 EV EV="0" when no event has occurred. When a Key ON event occurs, key data Key-On Event ——NOTE—————BLOCK———1 and l e v e l data are sent as a p a i r .
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YM2020 PKD2 1. OVERVIEW This LSI is an addressable PWM which uses 8-bit data to output pulses having the duty ratio set by data to the specified output pin. This PWM output permits the current flowing to the solenoids to be controlled, thereby allowing control of the piano's key touch.
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YM2020 Pin assignment ADDRESS DATA TABLE When CE is "0", output is enabled when D6 is "0". When CE is "1", output is enabled when D6 is "1".
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• DE (Touch Data Enable) This signal latches the latch information within the data. It modulates the pulse width of the output according to the data (00~7E) during DE = "0" status. D7 represents the Key ON/OFF data. ADDRESS DATA TABLE •...
Drive Unit,MIDI and Power Supply Circuit Board MIDI External Circuit Board Power Supply Circuit Board Drive Circuit Board...
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PARTS LIST CONTENTS 1. Electrical Parts 2. Control Unit 3. Key Stop Rail Assembly 4. Key Drive Unit 5. Key Sensor Unit 6. Hammer Sensor Unit, Air Damper Unit 7. Pedal Drive Unit, Pedal Sensor Unit, Pedal Cushion Unit 8. I/O Unit, Power Supply Unit, MIDI Unit...