Service Manual CASIO CTK-511 ELECTRONIC KEYBOARD

ELECTRONIC KEYBOARD CTK-511 CTK-511

CONTENTS Specifications ................................................................................................................................... 1 Block Diagram .................................................................................................................................. 2 Circuit Description ............................................................................................................................ 3 Adjustment ....................................................................................................................................... 7 Major Waveforms ............................................................................................................................. 8 Printed Circuit Boards ...................................................................................................................... 9 Schematic Diagrams ...................................................................................................................... 10 Exploded View ............................................................................................................................... 15 Parts List ........................................................................................................................................ 16

— 1 — SPECIFICATIONS GENERAL Keyboard: 61 standard-size keys, 5 octaves Tones: 100 Polyphony: 12 notes maximum (6 for certain tones) Auto accompaniment Rhythm patterns: 100 Tempo: Variable (236 steps, = 20 to 255) Chords: 2 fingering methods (CASIO CHORD, FINGERED) Rhythm controller: START/STOP, SYNCHRO/FILL-IN Accomp volume: 0 to 9 (10 steps) Song bank Tunes: 100 Controllers: PLAY/PAUSE, STOP, REW, FF, LEFT ON/OFF (ACCOMP), RIGHT ON/ OFF (MELODY) Display Name display: TONE, RHYTHM, SONG BANK name/number, keyboard settings name/value Tempo: Tempo value, metronome, synchro standby, beat indicator Chord: Chord name, Chord form Fingering: Fingering indicators, parts, pedal Song bank status: PLAY, PAUSE, REW, FF Staff: 5 octaves with sharp and flat indications Keyboard: 5 octaves MIDI: 5 multi-timbre receive Other functions Transpose: 12 steps (–6 semitones to +5 semitones) Tuning: Variable (A4 = approximately 440 Hz ± 50 cents) Volume: 0 to 9 (10 steps) Terminals MIDI terminals: IN, OUT Sustain terminal: Standard jack Phones/Output terminal: Stereo standard jack Output Impedance: 78 Ω Output Voltage: 4 V (RMS) MAX Power supply terminal: 9 V DC Power supply Dual power supply system Batteries: 6 D-size batteries Battery life: Approximately 8 hours on manganese batteries AC adaptor: AD-5 Auto power off: Turns power off approximately six minutes after last key operation. Enabled under battery power only, can be disabled manually. Speaker output: 2.0 W + 2.0 W Power consumption: 9 V --- 7.7 W Dimensions (HWD): 961 × 381 × 139 mm (37-7/8 × 15-1/16 × 5-1/2 inches) Weight: Approximately 5.4 kg (11.91 lbs) (without batteries) ELECTRICAL Current drain with 9 V DC: No sound output 250 mA ± 20% Maximum volume 830 mA ± 20% with 12 keys C1 to B1 pressed in Synth-Lead 1 Volume: Maximum Phone output level (Vrms with 8 Ω load each channel): with key G2 pressed in Synth-Lead 1 78 mV ± 20% Speaker output level (Vrms with 4 Ω load each channel): with key G1 pressed in Synth-Lead 1 1250 mV ± 20% Output level (Vrms with 47 KΩ load each channel): with key B1 pressed in Synth-Lead 1 1050 mV ± 20% Minimum operating voltage: 6.0 V

— 2 — BLOCK DIAGRAM CPU MSM 6755B-17 LSI2 Keyboard Buttons LCD LCD Driver SED1278F2A LSI3 Reset IC RN5VD40A IC1 Oscillator X1, Q1 Power Supply Circuit Q201 ~ Q203, Q207, Q208, D205 Power Amp. TA8248K IC201 Filter (L) Q206 Filter (R) Q205 Phone/Output VC VCC DVDD AVDD APO DC + 9V IN DB4 ~ DB7 MIDI IN MIDI OUT COM1 ~ COM16 SEG1 ~ SEG40 RS R/W E KO8 ~ KO12 KI0 ~ KI6 KO0 ~ KO7 MD0 ~ MD7 MA0 ~ MA18 ROM(2M-bit) LC372100PM- G48 LSI1 Power Switch

— 3 — CIRCUIT DESCRIPTION KEY MATRIX NOMENCLATURE OF KEYS KI0 KI1 KI2 KI3 KI4 KI5 KI6 KI7 KO0 C2 G#2 E3 C4 G#4 E5 C6 G#6 KO1 C#2 A2 F3 C#4 A4 F5 C#6 A6 KO2 D2 A#2 F#3 D4 A#4 F#5 D6 A#6 KO3 D#2 B2 G3 D#4 B4 G5 D#6 B6 KO4 E2 C3 G#3 E4 C5 G#5 E6 C7 KO5 F2 C#3 A3 F4 C#5 A5 F6 KO6 F#2 D3 A#3 F#4 D5 A#5 F#6 KO7 G2 D#3 B3 G4 D#5 B5 G6 KO8 — + 0 KO9 3 2 1 KO10 6 5 4 Rhythm Tone KO11 9 8 7 Fingered Normal Off KO12 FF Right Stop Left REW Tempo Down Tempo Up Start/ Stop Synchro/ Fill-In Chord Book Accomp Volume Transpose/ Tune/MIDI Song Bank CASIO Chord Play/ Pause Volume Down Volume Up F#3 G#3 A#3 C#4 D#4 F#4 G#4 A#4 C#5 D#5 F#5 G#5 A#5 F3 G3 A3 B3 C4 D4 E4 F4 G4 A4 B4 C5 D5 E5 F5 G5 A5 B5 C6 D#3 C2 D2 E2 F2 G2 A2 B2 C3 D3 E3 B6 A6 G6 F6 E6 D6 C7 C#3 A#2 G#2 F#2 D#2 C#2 A#6 G#6 F#6 D#6 C#6

— 4 — CPU (LSI2: MSM6755B-17) The CPU reads sound data from the ROM in accordance with the pressed key and the selected tone; the CPU can read rhythm data simultaneously when a rhythm pattern is selected. Then it provides the left and the right channels’ waveforms separately, by converting the data into the waveforms with two built-in DACs. The CPU also controls key and button input. The following table shows the pin functions of LSI2. Pin No. Terminal In/Out Function 1 MA14 Out Address bus 2, 3 NCO — Not used 4 ~ 19 MA0 ~ MA13 Out Address bus 13 MRDB Out Read enable signal 17 MCSB — Not used 20 ~ 27 MD0 ~ MD7 In/Out Data bus 28, 29 NC1, NC2 — Not used 30 DGND In Ground (0 V) source 31 DVCC In +5 V source 32, 33 XTLO, XTLI In/Out 20 MHz clock input/output 34 NC3 — Not used 35 RSTB In Reset signal input 36 P24/RXD In MIDI signal input 37 P25/TXD Out MIDI signal output 38 NMI In Power ON signal input. Connected to +5 V. 39 APO Out APO (Auto Power Off) signal output 40 NC4 — Not used 41 REFH Out Terminal for the internal DAC 42, 43 NC5, NC6 — Not used 44 DAOR Out Right channel sound waveform output 45 NC7 — Not used 46 AVdac In +5 V source for the internal DAC 47 DAOL Out Left channel sound waveform output 48 REFL Out Terminal for the internal DAC and ADC 49 AGdac In Ground source for internal DAC 50 AGadc In Ground source for internal ADC 51 ANI In APO cancellation signal 52 AVadc In +5 V source for the internal ADC 53 NC8 — Not used 54 MOD0 In Mode selection terminal. Connected to +5 V. 55, 56 MOD1, MOD2 In Mode selection terminal. Connected to ground. 57 P40 In Pedal signal input 58 ~ 64 KI0/P30 ~ KI7/P36 In Terminals for key/button input signal 65 KI7/P37 — Not used 66 ~ 73 KO0/P50 ~ KO7/P57 Out Terminals for key scan signal

— 5 — LCD DRIVER (LSI3: SED1278F2A) The LCD driver can drive a dot matrix LCD having 40 segment and 16 common lines. The LSI contains 240 graphic symbols in the built-in character generator ROM, and stores 80 characters in the built-in display data RAM. In accordance with command from the CPU, the LSI is capable of displaying up to 16 characters simultaneously. The following table shows the pin functions of LSI3. Pin No. Terminal In/Out Function 74 ~ 77 DB4 ~ DB7 Out Data bus for the LCD driver 78 NC9 — Not used 79 LVCC In +5 V source 80 ~ 84 KO8 ~ KO12 Out Terminals for button scan signal 85 ~ 87 P65 ~ P67 — Not used 88 RS Out Control signal for the LCD driver 89 R/W Out Read/Write signal for the LCD driver 90 E Out Chip enable signal for the LCD driver 91 ~ 95 P73 ~ P77 — Not used 96 LGND In Ground source 97, 100 MA18, MA15 Out Address bus Pin No. Terminal In/Out Function 1 ~ 22, 63 ~ 80 23 VSS — GND (0 V) source Terminals for the built-in clock pulse generator. The external resistor connected determines the oscillation frequency. LCD drive voltage input. 26 ~ 30 V1 ~ V5 In Those voltages are used for generating the stepped pulse of the LCD drive signals. 31, 32 LP, XCLS — Not used 33 VDD In DVDD (+5 V) source 34, 35 FR, DO — Not used Data/command determination terminal. High: data, Low: command 37 R/W In Read/Write terminal. High: read, Low: write Chip enable signal. 38 E In High: enable, the writing is done at fall edge. Low: disenable 39 ~ 42 DB0 ~ DB3 — Not used. Connected to GND (0 V) 43 ~ 46 DB4 ~ DB7 In/Out Data bus 47 ~ 62 COM1 ~ COM16 Out Common signal/output SEG1 ~ SEG40 Out Segment signal output 24, 25 OSC1, OSC2 In/Out 36 RS In

— 6 — FILTER BLOCK Since the sound signals from the CPU is stepped waveforms, the filter block is added to smooth the waveforms. POWER AMPLIFIER (IC201: TA8248K) The power amplifier is a two-channel amplifier with standby switch. The following table shows the pin function of IC201. Pin No. Terminal In/Out Function 1 NC — Not used 2 B.S.2 — Terminal for a bootstrap capacitor 3 OUT2 Out Channel 2 output 4 VCC In +9 V source 5 OUT1 Out Channel 1 output 6 B.S.1 — Terminal for a bootstrap capacitor 7 Power GND In Ground (0 V) source 8 Stand by In Power control signal input. 0 V: Off, +9 V: On 9 DC — Terminal for a decoupling capacitor 10 NF1 In Negative feedback input 11 IN1 In Channel 1 input 12 IN2 In Channel 2 input 13 NF2 In Negative feedback input 14, 15 Pre GND In Ground (0 V) source Amp. TA8248K Filter Block CPU MSM6755B-17

— 7 — Output Set Voltmeter R62 3) Equipment connection/Procedure Vop voltage setting Input Connection Input Point Input Signal Adjust Output Connection Output Point Adjust for VR1 Voltmeter R62 Adjust for 4.40 ~ 4.46 V reading on voltmeter under the temparature 20 ~ 25 °C. Make fine adjustment accord- ing to the following instruc- tion. Watching the LCD at a 37° angle to the horizontal, adjust Vop voltage so that unenergized segments are seen dimly. ADJUSTMENT MAIN PCB 1) Items to be adjusted: 2) Adjustment and Test Point Locations (TOP VIEW) Item Measuring Instrument Vop voltage setting Voltmeter 37° LCD Eye (BOTTOM VIEW) Test point VR1

— 8 — MAJOR WAVEFORMS 1 Clock pulse MSM6755B-17 pin 32 1 2 Power source DVDD JC connector pin 8 3 APO signal JC connector pin 2 2 3 4 Sound waveform (R-ch) Tone: Whistle (59) JC connector pin 5 Key: A4 5 Sound waveform (L-ch) Volume: Max. JC connector pin 4 4 5 6 Button scan signal KO0 MSM6755B-17 pin 66 7 Button scan signal KO1 MSM6755B-17 pin 67 6 7 8 LCD common signal COM6 SED1278F2A pin 52 9 LCD common signal COM7 SED1278F2A pin 53 8 9

Service Manual CASIO CTK-511 ELECTRONIC KEYBOARD

You're Reading a Preview

Recently Viewed