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Alesis MidiVerb IV Service Manual‘

7

03/05/99

7.00 Test Procedures

If possible, user data should be saved (an Alesis DataDisk is recommended for this task)

prior to any servicing. This, of course, may not always be possible (i.e. dead power supply, bad
reset signal, corrupt data, etc.). Saving user data may also be accomplished after unit
functionality is restored (i.e. power supply, or reset line, is repaired), and prior to further
servicing, and testing. The unit should always be reinitialized (power unit up while holding
"PROGRAM" and "D" buttons down) after changing the EPROM, or SRAM.

7.10 Self Test

The built in test software, as in  other Alesis products, provides basic diagnostics and

tests to ensure unit functionality. A MIDI cable MUST be inserted between MIDI IN and OUT
before initiating the test. To initiate the self test hold "A" and "D" while powering the unit up. The
unit will then proceed to test the following:

A

LEDs-All front panel LEDs are lit sequentially and immediately proceeds to the next test.

A

ROM-CHECKSUM-Checks the ROM’s checksum for accuracy and immediately proceeds to
the next test.

A

MIDI TEST-Checks MIDI I/O and immediately proceeds to the next test.

A

RAM TEST-Checks internal memory for correct operation and immediately proceeds to the
next test.

A

SWITCHES/ENCODER-Pressing Individual front panel buttons causes their function to be
displayed on the LCD. Rotating the DATA KNOB causes it’s direction to be displayed. Power
the unit down to exit the self test routines.

7.20 Further Testing.

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Use a clean audio source (CDs preferred) and set up the unit according to the user’s
manual.

/

Listen to the wet (effects) output for any distortion.

/

Use the Data Knob to change the input and output levels through their full range to ensure
the correct operation of the DigPots.

/

To ensure that the shaft encoder is functioning properly all programs should be listened to
briefly.

/

Turn the input level all the way down, and the output level all the up.

/

Listen for excessive noise in the noise floor.

/

Send and receive all user programs via MIDI to ensure MIDI operation.

/

As a final check it’s a good idea to physically shake the unit so that no loose parts remain
inside the unit.

Содержание MIDIVERB IV

Страница 1: ...Alesis MidiVerb IV Service Manual i 03 05 99 Alesis MIDIVERB IV STEREO EFFECTS PROCESSOR Service Manual V 1 00 6 13 95...

Страница 2: ...ervices or repairs were done in accordance with the Manual All service or repairs done by you or with reference to the Manual shall be solely your responsibility and Alesis shall have no liability for...

Страница 3: ...ch accompanies the product CAUTION Danger of explosion if battery is incorrectly replaced Replace only with the same type or equivalent type recommended by the equipment manufacturer Battery Manufactu...

Страница 4: ...stoves heat registers radiators or other heat producing equipment 7 Ventilation When installing the product make sure that the product has adequate ventilation Improperly ventilating the product may c...

Страница 5: ...as capacitors that begin to leak excess current after a significant amount of time 5 Cable Checks Wiggling cables can reveal intermittent failures such as loose cables or poorly soldered headers Remem...

Страница 6: ...s 3 5 10 RESET 3 5 20 M4 ASIC 3 6 00 The Front Panel 5 6 10 The Keypad 5 6 20 Display LEDs 5 6 30 Disassembly 5 7 00 Test Procedures 7 7 10 Self Test 7 7 20 Further Testing 7 8 00 Troubleshooting 8 9...

Страница 7: ...for use by the LCD 2 10 Battery Backup Battery backup is actually more complicated than it might first appear as it depends on a good system reset see section 5 10 for details in order to function pr...

Страница 8: ...filters for the internal voltage reference C35 along with R34 and R35 act as filters for the negative and positive internal DAC reference inputs Analog power is supplied through current limiters R52...

Страница 9: ...the M4 ASIC When the raw supply reaches approximately 7 volts the transistor will turn on causing the reset line to drop low The opposite should occur on power down transistor turns off at 7V threshol...

Страница 10: ...control of the M4 ASIC 44 SRAMWR SRAM WRite enable Enables writing to the SRAM directly under the control of the M4 ASIC 19 M12CLK 12 Mhz CLocK 20 M3CLK 3 Mhz CLocK 21 LRCLK Left Right CLocK Used to...

Страница 11: ...front panel LEDs go bad they should be fairly easy to replace using the disassembly procedure outlined below If all of the LEDs are dead then the 74HC138 U3 is probably bad and should be replaced fir...

Страница 12: ...Alesis MidiVerb IV Service Manual 6 03 05 99 Diagram 1 Diagram 2...

Страница 13: ...next test A ROM CHECKSUM Checks the ROM s checksum for accuracy and immediately proceeds to the next test A MIDI TEST Checks MIDI I O and immediately proceeds to the next test A RAM TEST Checks intern...

Страница 14: ...ize memory and retest Power unit up while holding A and D Faulty SRAM Reinitialize memory and retest Power unit up while holding A and D Faulty LCD Module Test with known good front panel Replace if n...

Страница 15: ...Alesis MidiVerb IV Service Manual 9 03 05 99 9 00 Schematics...

Страница 16: ...Alesis MidiVerb IV Service Manual 10 03 05 99...

Страница 17: ...Alesis MidiVerb IV Service Manual 11 03 05 99...

Страница 18: ...Alesis MidiVerb IV Service Manual 12 03 05 99...

Страница 19: ...longer compatible with older versions The REVERSE REVERB Configuration has been renamed to NONLINEAR It is the same as the old Configuration except now it has a Dir Reverb Direction parameter which ca...

Страница 20: ...erb IV Service Manual 14 03 05 99 Renamed User 106 from Model147 to Model122 Now to finish the Switch Encoder Test you press Page A it used to be Input Output V1 00 11 19 94 Checksum 77C8 First Produc...

Страница 21: ...the MIDI channel of a MidiVerb 4 it can use transmit the MIDI universal system exclusive inquiry message with the channel byte set to 7F ALL CALL The MidiVerb 4 will respond with a universal system ex...

Страница 22: ...Nibble Footswitch Mode see Footswitch Modes System Status Byte see System Status Byte Modulator Definitions 0 Pitch Bend 1 Aftertouch 2 Note Number 3 Velocity 4 Controller 0 123 Controller 119 Modulat...

Страница 23: ...ays zero Configuration 0 31 8 Byte Name 16 Parameters nibblized so transmit as 32 bytes ALL USER PROGRAMS DATA The All User Programs data consists of 128 Program Data Blocks defined above SINGLE PROGR...

Страница 24: ...P ZNC 1 HOLDS REGULATOR 7805 TO PCB HDW 5 02 6320 NUT KEP 6 32 1 HOLDS REGULATOR 7805 TO PCB IC 2 31 0060 IC SOFTWARE VER 1 03 EPROM M4 1 MAIN U2 IC 2 27 0032 ASIC POT 4 CHANNEL DIGITAL M4 1 IC 2 11 7...

Страница 25: ...P SMD 2 MAIN U7 8 SMI 2 64 0138 IC 74HC138 DEMUX DEC SMD 1 FP U3 SMM 2 50 4148 DIODE SIGNAL 1N4148 SMD 5 MAIN D7 D11 SMM 2 51 4401 TRANS 2N4401 NPN SMD 3 MAIN Q1 3 SMM 2 50 4148 DIODE SIGNAL 1N4148 SM...

Страница 26: ...Alesis MidiVerb IV Service Manual 20 13 00 Service Manual History 6 13 95 V1 00 1st Release...

Страница 27: ...CDATA 4 data buss 3 DATA KNOB 7 DataDisk 7 digital supply 2 digital to analog 2 DigPot 3 8 DigPots 1 2 7 DSPSRAMOE 4 E encoder 5 7 14 18 22 EPROM 3 7 F FROMADC 2 4 front panel 3 5 7 8 19 I I O ports 3...

Страница 28: ...XD 3 S S1 1 sample and hold 2 Sigma Delta 2 SRAM 1 3 4 7 8 19 SRAMA0 16 4 SRAMCE 3 SRAMD0 7 4 SRAMWR 4 standby current 1 stereo output 2 SWITCHES ENCODER 7 T Transmit Serial Data 3 TXD 3 U U10 3 19 U1...

Страница 29: ...Alesis MidiVerb IV Service Manual 23 03 05 99 NOTES...

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