Alesis_D4,_DM5_Drum_Module_Service_Manual电路图.pdf

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1、Alesis D4/D5 Drum Modules Service Manual i 02/19/03 ALESIS D4/DM5 Drum Modules Service Manual V1.00 10/17/95 RadioFans.CN 收音机爱 好者资料库 Alesis D4/D5 Drum Modules Service Manual ii 02/19/03 PREFACE This document is intended to assist the service technician in the operation, maintenance and repair of the

2、 D4/DM5 Drum Modules. Together with the D4 and DM5 Reference Manuals, this document provides a complete description of the functionality and serviceability of the D4 and DM5. Any comments or suggestions you may have pertaining to the document are welcome and encouraged. WARNINGS TO REDUCE THE RISK O

3、F ELECTRIC SHOCK OR FIRE, DO NOT EXPOSE THIS PRODUCT TO WATER OR MOISTURE. CAUTION RISK OF ELECTRIC SHOCK DO NOT OPEN The arrowhead symbol on a lightning flash inside a triangle is intended to alert the user to the presence of un-insulated dangerous voltage within the enclosed product which may be o

4、f sufficient magnitude to constitute a risk of electric shock to persons. The exclamation point inside a triangle is intended to alert the user to the presence of important operating, maintenance and servicing instructions in the literature which accompanies the product. REPAIR BY ANY PERSON OR ENTI

5、TY OTHER THAN AN AUTHORIZED ALESIS SERVICE CENTER WILL VOID THE ALESIS WARRANTY. PROVISION OF THIS MANUAL DOES NOT AUTHORIZE THE RECIPIENT TO COMPETE WITH ANY ALESIS DISTRIBUTOR OR AUTHORIZED REPAIR SERVICE CENTER IN THE PROVISION OF REPAIR SERVICES OR TO BE OR MAKE REPAIRS AS AN AUTHORIZED SERVICE

6、CENTER. ALL REPAIRS DONE BY ANY ENTITY OTHER THAN AN AUTHORIZED ALESIS SERVICE CENTER SHALL BE SOLELY THE RESPONSIBILITY OF THAT ENTITY, AND ALESIS SHALL HAVE NO LIABILITY TO THAT ENTITY OR TO ANY OTHER PARTY FOR ANY REPAIRS BY THAT ENTITY. RadioFans.CN 收音机爱 好者资料库 Alesis D4/D5 Drum Modules Service M

7、anual iii 02/19/03 SAFETY SUGGESTIONS Carefully read the applicable items of the operating instructions and these safety suggestions before using this product. Use extra care to follow the warnings written on the product itself and in the operating instructions. Keep the operating instructions and s

8、afety suggestions for reference in the future. 1. Power Source. The product should only be connected to a power supply which is described either in the operating instructions or in markings on the product. 2. Power Cord Protection. AC power supply cords should be placed such that no one is likely to

9、 step on the cords and such that nothing will be placed on or against them. 3. Periods of Non-use. If the product is not used for any significant period of time, the products AC power supply cord should be unplugged from the AC outlet. 4. Foreign Objects and Liquids. Take care not to allow liquids t

10、o spill or objects to fall into any openings of the product. 5. Water or Moisture. The product should not be used near any water or in moisture. 6. Heat. Do not place the product near heat sources such as stoves, heat registers, radiators or other heat producing equipment. 7. Ventilation. When insta

11、lling the product, make sure that the product has adequate ventilation. Improperly ventilating the product may cause overheating, which may damage the product. 8. Mounting. The product should only be used with a rack which the manufacturer recommends. The combination of the product and rack should b

12、e moved carefully. Quick movements, excessive force or uneven surfaces may overturn the combination which may damage the product and rack combination. 9. Cleaning. The product should only be cleaned as the manufacturer recommends. 10. Service. The user should only attempt the limited service or upke

13、ep specifically described in the operating instructions for the user. For any other service required, the product should be taken to an authorized service center as described in the operating instructions. 11. Damage to the Product. Qualified service personnel should service the unit in certain situ

14、ations including without limitation when: a. Liquid has spilled or objects have fallen into the product, b. The product is exposed to water or excessive moisture, c. The AC power supply plug or cord is damaged, d. The product shows an inappropriate change in performance or does not operate normally,

15、 or e. The enclosure of the product has been damaged. RadioFans.CN 收音机爱 好者资料库 Alesis D4/D5 Drum Modules Service Manual iv 02/19/03 Table of Contents PREFACE.ii WARNINGS .ii SAFETY SUGGESTIONS.iii 1.00 General Descriptions.1 2.00 Power Supply.2 2.10 Battery Backup.2 2.20 PUP Circuit.3 3.00 Digital Si

16、gnal Paths.3 3.10 The 8031 .3 3.11 Reset.3 3.12 Memory mapped I/O.4 3.13 Data Entry Knob And Footswitches .4 3.14 Keypad Decoding.4 3.15 MIDI.4 3.20 DM3AG ASIC .4 3.21 Address Buss Decoding.5 3.30 Mask ROMS.6 4.00 Analog Signal Paths.6 4.10 D4 Audio Output.6 4.11 D4 Headphone Output .6 4.20 D5 Audio

17、 Output.6 4.21 D5 Headphone Output .7 4.30 Trigger Inputs .7 4.30 Analog-Digital Conversion.7 5.00 Test Procedures.7 5.10 D4 Self Test.8 5.20 D5 Self Test.8 5.30 Further Testing.9 6.00 Updates and Corrections.10 6.10 D4 Updates.10 7.00 Common Solutions.11 8.00 Service Parts Lists .12 8.10 D4 Service

18、 Parts List.12 8.20 D5 Service Parts List.14 9.00 D4 Software History .16 9.10 Version 1.01 .16 9.20 Version 1.02 .16 9.30 Version 1.03 .17 9.40 Version 1.04 .17 10.00 D5 Software History .18 10.10 Version 1.01 .18 11.00 MIDI Implementation.19 12.00 Service Manual History .28 13.00 Schematics.29 13.

19、10 D4 Schematics .29 13.20 D5 Schematics .31 13.30 D5 Component I.D.34 INDEX.36 Alesis D4/D5 Drum Modules Service Manual 1 02/19/03 1.00 General Descriptions The D4 is a rather simple unit to repair, as the component count has been greatly reduced by the use of the DM3AG ASIC (Application Specific I

20、ntegrated Circuit). The basic building blocks of the unit are the 8031 micro controller (which handles all basic unit functions such as triggers , LCD output, Keypad input, and MIDI I/O), sample generation circuits (ASIC, DAC, Analog switch, and output filter/buffers), and some miscellaneous support

21、 circuits such as system reset, battery backup, etc. The DM5 (Alesis product code D5) is extremely similar in design, with the one major difference being the use of better DACs. This has required the addition of on extra IC D56IFT ASIC for the purpose of converting parallel data to a serial format a

22、nd generating clock signals for use with the new DACs. In addition this IC consolidates several other functions previously performed by discreet logic such as memory map decoding and handling the highest order Mask ROM addressing lines. Please note that there are several main PC Board revisions, and

23、 some differences will be noticed from unit to unit. Reference designators refer to the D4 unless in brackets D5 reference or otherwise noted. Diagram 1 Alesis D4/D5 Drum Modules Service Manual 2 02/19/03 Diagram 2 2.00 Power Supply The power supply begins with the 9V A.C. 750 mA transformer (Alesis

24、 P3 type). After being R.F. filtered by C26, and passing through the power switch, the A.C. is rectified into -12V, and +12V by D1 D10, D2 D11, and C2/C3 C111/C112, C1 C108. Regulators supply the +5V and -5V needed to run the unit. Note that the +12V raw supply (From D2) D11 is used by the system re

25、set circuit (see section 3.11) and battery backup (section 2.10). The D4s +12V and - 12V lines are also used to power the output op-amps via the PUP Circuit (section 2.20). +5V and -5V lines are used to power the PUP circuit in the D5. 2.10 Battery Backup The battery backup circuit is more complex t

26、han it first appears, as it requires a good system reset (see section 3.11) to function properly. The actual backup circuit consists of the 3V battery, a current testing resistor (R38) R92, a steering diode (D6) D2, a Diode/Transistor/Resistor combination (D7, Q3, R24) D1, Q6, R85 that acts as a ste

27、ering diode, and filter capacitor C33 C27. The D/T/R combination serves a duel purpose. Besides acting as a steering diode, it also ensures that the supply voltage level of the SRAM is higher than the level of the data buss. This prevents data corruption during normal operation. Alesis D4/D5 Drum Mo

28、dules Service Manual 3 02/19/03 As mentioned before, the reset circuit is extremely important to battery backup. While covered more extensively in later sections, it should be noted here that it ties into backup system at the SRAMs chip enable line (pin 20) via Q4, and ensures that all access to the

29、 SRAM is shut off during power up, and power down. In the case of the D5, reset is tied in through the D56IFT ASIC and Q5. Any time any part of the backup circuit (including the SRAM) is changed, battery current should be checked. This is accomplished by measuring the voltage across R38 R92. Specifi

30、cation for this is 1mVVR76 A15 must be low (i.e. the 8031 is accessing the lower 32K of address space). 2 The 8031 WRite line must be active (the 8031 is performing a memory write). A15 is used to directly control which function (memory or I/O) is active. Once U12 is enabled, addresses A12-A14 are d

31、ecoded by it, and the latch corresponding to the value of the decoded address is strobed. At this point, data on the 8031 data buss is written into the latch. 3.13 Data Entry Knob And Footswitches The data entry knob and footswitches are read via the memory mapped latch U11 U22. This allows the 8031

32、 to directly read any changes in the status of these inputs. 3.14 Keypad Decoding The keypad is handled through a simple polling matrix implemented through the memory mapped latches U10 and U11 U20, U22. Each row is tested by the 8031, one at a time, via U10 U20. Any closed switches are read into U1

33、1 U22, and passed along to the 8031 for interpretation. 3.15 MIDI The MIDI hardware is a standard implementation. MIDI out/thru begins at the 8031s TXD port (pin 11) and is buffered with two inverters of U7 U27. MIDI in consists mostly of the opto isolator (U8) U23, protection diode D4 D6, pullup R1

34、8 R128, and threshold resistor R19 R129. 3.20 DM3AG ASIC The DM3AG ASIC is a complex LSI device, specifically designed for the purpose of playing percussion samples. Obviously, the internal workings of such a device are beyond the scope of this manual, however, a brief description of the important p

35、ins follows. Alesis D4/D5 Drum Modules Service Manual 5 02/19/03 NAME PIN#(s) Function MD0-MD7 27-34 8031 Data Buss Input. CLOCK 37 Asic Clock Input (8MHz in SR-16). DAC0-DAC16 42-51, 53-60 Output to DAC. A0-A19 3-17, 19-23 Mask Address Buss D0-D7 61-68 Mask Rom Data Buss SNH0 39 Output Sample and H

36、old Control SNH1 40 SNHIN 41 Output Sample and Hold Inhibit. STRES 26 Instruction reset strobe. STB 25 Instruction latch strobe. 3.21 Address Buss Decoding Due to the fact that we are pushing the ASIC beyond its original design, a little extra hardware was required to accomplish the design goals of

37、the D4. Two limitations needed to overcome. 1 The address space directly accessible wasnt enough for all of the samples. 2 The ASIC clock speed was increased from earlier designs to 12MHz, making extra communication from the 8031 more difficult. This solution to these problems takes the form of an a

38、synchronous decoder. The purpose of the decoder is to act as an extra set of address lines to ensure that only one Mask ROM is enabled at any given time. Diagram 5 Diagram 2 Alesis D4/D5 Drum Modules Service Manual 6 02/19/03 Two bits are required for each sample read (6 Mask ROMs, 0-5). This, plus the fact that there are sixteen voices available means that 3