SM-Z-89-37 Double-Density Disk Controller Service Manual 2NI'N ~ data systems 581;-8 ZENITH DATA SYSTEMS SAINT JOSEPH, MICHIGAN 49085 Copyright © 1982 Zenith Data Systems 1).
111..... DOUBLE-DENSITY DISK CONTROLLER Table of Contents SPECIFICATIONS RECONFIGURATION 'fo Change the Internal Drive To Rearrange the Drive Numbers Programming Modules 1-1 2-1 " 2-1 2-3 2-7 CIRCUIT DESCRIPTION 3-1 Control Lines (P2) 3-2 Ul Data Buffer and U7B Buffer Direction Control. . . . . . . . . . . . . . . . . . .. 3-2 U2, U3, U4 Interrupt Control 3-2 U5 Open Collector NAND Gates 3-2 U6 Control Decoder and Inverter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..
- - -.....1111 DOU8LE·DEItIITY DISK CONTROlLER General Drive/Controller Diagnostic Initiating the General Drive/Controller Diagnostic Available Tests and Options F.,...Format Disk Surface ...........................•............... T-Drive Speed , , D-General Drive Checkout ................................•.... ,. M-Media Check S-Seek Time A-Align " " U-Switch E-Exit ...................................................•......
IV IL' DOUBLE-DENSITY DISK CONTROLLER u u u
DOUBLE-DENSITY DISK CONTROLLER Specifications The Z-89-37 Double-Density Disk Controller interfaces the Z-89/90 Computer with the Z-37 Floppy Disk.* The Controller will read and write to drives using SOFT-SECTORED DISKS as follows: Double-Sided (H-17-4 drives): 96 tracks per inch 80 tracks per side Single or double density Single-Sided (H-17-1 drives): 48 tracks per inch 40 tracks Single or double density Required software is: HDOS version 2.0 modified (or higher) or CP/M version 2.2.
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12.,1 DOUBLE-DENSITY DISK CONTROLLER Reconfiguration To reconfigure the system, choose the instructions below that fit the application and perform those steps. TO CHANGE THE INTERNAL DRIVE... To change the internal drive from handling hard-sectored diskettes to handling softsectored diskettes: Refer to Figure 2-1 for the following steps. • Open the cabinet shell.
2-21_-- - - - - - - - - - DOUBLE-DENSITY DISK CONTROLLER • Set switch SW501, section 4 (on the CPU logic circuit board) to 1. The Z-37 connected drives are now the primary drives and they are now numbered as shown in Figure 2-3 on Page 2-3. (NOTE: IF YOU REMOVE THE UNUSED H-88-1 FLOPPY DISK I/O CIRCUIT BOARD, YOU MUST CONNECT A 4700 OHM RESISTOR TO PLUG P512 BETWEEN PINS 1 AND 12. SEE FIGURE 2-2.
DOUBLE-DENSITY DISK CONTROLLER _ _ _ _ _ _ _ _ _1. 2:-3 TO REARRANGE THE DRIVE NUMBERS... Refer to the following chart and Figure 2-3, and select the configuration that fits your situation. Configuration E is normally used for transferring data and programs from hard-sectored disks to soft-sectored disks. After you select the configuration you want, refer to Figure 2-4 on Page 2-4 to program any 48 TPI (H-17-1) drives, or Figure 2-5 on Page 2-5 to program any 96 TPI drives.
2-4 IL DOUBLE-DENSITY DISK CONTROLLER u HARDWARE UNIT ZERO (DS1) HARDWARE UNIT ONE (DS2) [,,.,.J ~ ~Ir--_~ CUT [~~~,~J ~I,n,~"l PROGRAMMING MODULE HARDWARE UNIT TWO (DS3) INSET B L ODD H~MSSSH M K X3 2 1 S ~ '----~} NOTE: CONNECTOR PINS AT HM MUST REMAIN OPEN lUNSHORTENEDl. Figure 2-4 Single-sided drives (H-17-1) programmed for Z-89-37 Controller.
----l12.. 5 DOUBLE-DENSITY DISK CONTROLLER Hardware Unit Zero (OS1) ~,.,-'+'.'.1.i ('.1-1.'.1.J PROGRAMM I NG MODULE Hardware Unit One (052) f,·,-'·'·'·l-l. ~ ('.1'1-'-'-1-~ PROGRAMM I NG MODULE Hardware Unit Two (053) ~'.'-'-'-'.1-1-i ['.l.l.,.,.J PROGRAMM I NG MODULE Figure 2-5 Double-sided drives (H-17·4) programmed for Z·89-37 Controller.
2-6 1L- DOUBLE-DENSITY DISK CONTROLLER u HARDWARE UNIT ZERO I I HARDWARE UNIT ONE , ) I.. ".J~ CUT I~~~,~J ul~ u ",1_ _ ---. PROGRAMMING MODULE HARDWARE UNIT TWO [,~-J Figure 2-6 Single-sided drives (H-17-1) programmed for H-88-1 Controller.
DOUBLE-DENSITY DISK CONTROLLER _ _ _ _ _ _ _ _ _ _12:-7 , PROGRAMMING MODULES Refer to Figure 2-7 on Page 2-8 as you read the following information. Use the following information for any special configurations that you may want. Programming modules: J1 & J2 Select port 170 or 174. (Both jumpers must be at 170, or both jumpers must be at 174. 170 is normal.) J3 o = No precompensation; 1 = precompensation. (0 position is normal.) Use "0" only on Wangco drives. Otherwise, use "1.
2-8 ,~ DOUBLE-DENSITY DISK CONTROLLER u u Figure 2·7 Z-89-37 Double-Density Disk Controller Board. Part number HE 181-3614.
DOUBLE-DENSITY DISK CONTROLLER Circuit Description Refer to the Block Diagram (fold-out from Page 4-1) while you read the following Circuit Descriptions. The board's function is to translate the instructions of the processor to the disk drives. Assume that the processor wants to write on disk drive number one. First, the processor sends the proper enabling and control signals over the control lines. These signals are made compatible with the 1797 disk controller by the control decoder and inverter.
3-2 1L... DOUBLE-DENSITY DISK CONTROLLER CONTROL LINES (P2) Please refer to the Schematic Diagram (fold-in) while you read this description. All of the disk control lines from the processor are input to U6 via plug P2, except for the processor system clock line, which is input to U5A via pin 13 of P2. The control lines consist of address lines AO, Ai, and A2, read line RD, write line WR, I/O DISK, I/O FLPY, and the reset line RESET.lAddress line A2 is inverted by U5Bwhen J1A is jumpered.
DOUBLE-DENSITY DISK CONTROLLER U6 CONTROL DECODER AND INVERTER U6 is a programmable logic array, designed to decode address and read and write conditions for the controller board. Using addresses AO, Al, and A2 it determines whether the board is being addressed, which register is being addressed, and whether the signal is a read enable or write enable signal. The internal logic of U6, and most other ICs on the board, is shown in the "Semiconductor Identification Chart.
3-4 1l.... DOUBLE-DENSITY DISK CONTROLLER U14 RAW READ LATCH U14lengthens the raw read pulse from the disk drive electronics to a size readable by the 1797 (U12). U15 DRIVE BUFFER U15 buffers the control and data signals to the two drive interfaces. U16, U17, U18, Q1, AND Q2 PHASE LOCK LOOP TRACKING AND PRECOMPENSAnON U16 supplies U17 with either a pull-up (PU) or pull-down (PD) signal. This signal is then filtered by C29 and R13 and then called FC - frequency control.
DOUBLE-DENSITY DISK CONTROLLER ----'1 4-1 P2 p------~-------------~-------------------------------------------------~-----------------------------------------------, . - -. • I ,I DATAB4S PI; 10-9) __ .
4-2 1L- DOUBLE"DENSITY DISK CONTROLLER TO REARRANGE THE DRIVE NUMBERS... Refer to the following chart and Figure 4-1, and select the configuration that fits your situation. Configuration E is normally used for transferring data and programs from hard-sectored disks to soft-sectored disks. After you select the configuration you want, refer to Figure 4-2 on Page 4-3 to program any 48 TPI (H-17-1) drives, or Figure 4-3 on Page 4-4 to program any 96 TPI drives.
14..3 DOUBLE-DENSITY DISK CONTROLLER HARDWARE UNIT ZERO (DS1) HARDWARE UNIT ONE (DS2) I . [::J I .,.., .. ., .... ..,., I ~n ~ I: :22, J CUT HARDWARE UNIT TWO (DS3) I ..., 7 . . . . .... -,-. I Figure 4-2 Single-sided drives (H-17-i) programmed for 2-89-37 Controller.
4-41 DOUBLE-DENSITY DISK CONTROLLER HARDWARE UNIT ZERO (051) n ll-l-l-l-l-l-l~ 1..1-..1 PROGRAMM I NG MODULE HARDWARE UNIT ONE (052) n ll-l-l-l-l-l-l~ l..1-3 PROGRAMM I NG MOD ULE HARDWARE UNIT TWO (053) ~l-l-l-l-l-l-l-~ (l-l-l-l-l-l.~ l,.l-l-l-l-l-l~ (.1- j PROGRAMM I NG MODULE Figure 4-3 Double-sided drives (H-17-4) programmed for 2-89-37 Controller.
_ 14..5 DOUBLE-DENSITY DISK CONTROLLER HARDWARE UNIT ZERO t ) I I HARDWARE UNIT ONE HARDWARE UNIT TWO Figure 4-4 Single-sided drives (H-17-1) programmed for H-88-1 Controller.
4-6 1i....- DOUBLE-DENSITY DISK CONTROLLER STARTING THE DIAGNOSTIC PROGRAMS To start the diagnostic programs, boot up the system using either the hard- or softsectored Diagnostic and Conversion Utilities diskette. The part number for the hardsectored diskette is HE 890-156. The part number for the soft-sectored diskette is HE 890-157. Greater centering accuracy is required when you are using 96 TPI drives.
DOUBLE-DENSITY DISK CONTROLLER o 4. 'Type the letter B and press the RETURN key. The terminal will display: H: Boot You will hear some clicking noises from the disk drive. This is normal. You will hear such noises whenever the Computer is reading from or writing to the diskette. The clicks will continue for about 15 seconds.
4-8 1'-- DOUBLE-DENSITY DISK CONTROLLER DISK CONTROLLER CHECKOUT The Disk Controller Checkout is used to verify the operation of the Z-89-3 7 disk controller circuit board. This diagnostic program turns on the disk drive motors, loads the disk drive read/write heads as a program would if it were trying to read from or write to the disk, and then tries to position and reposition the read/write head.
DOUBLE-DENSITY DISK CONTROLLER To respond to this question, check to make sure the red light on drive 0 is glowing. If it is, enter Y. Otherwise, enter N and turn to Page 4-13 for an explanation of the message you receive. If you have responded Y to the preceding question, the system will print: Selecting Drive One. If this is a non-existent drive for your system, Answer 'y' to the following question.
4-10 ,'-- DOUBLE-DENSITY DISK CONTROLLER DISK CONTROLLER CHECKOUT ERROR MESSAGES Prompt: Are All Drive Motors Turning? If they are not turning, be sure that power is applied to the unit, and the cables are plugged in correctly. Then repeat this test. First, check to make sure that the power to the drive is on. If the power is on, check the connection of the ribbon cable on the controller circuit board (this is the third circuit board to the immediate left of the disk drive).
DOUBLE-DENSITY DISK CONTROLLER GENERAL DRIVE/CONTROLLER DIAGNOSTIC The General Drive/Controller Diagnostic, or TEST, is a diagnostic utility used to test soft-sectored 5.25-inch diskettes and 5.25-inch disk drives. TEST verifies the drive rotational speed, drive step rate, read/write mechanism, and the quality of the recording surface of the diskette used for the tests.
4- 12 1"-- DOUBLE-DENSITY DISK CONTROLLER TEST will now ask for the hardware unit number of the drive you want tested. For example: WHICH DRIVE (0/1/2)? At this prompt, enter the hardware unit number of the drive which you want to test and press RETURN. If this is your first time through the test, we recommend that you test drive o.
DOUBLE-DENSITY DISK CONTROLLER When you have inserted a soft-sectored diskette and pressed RETURN, the system will print: Double Density ? If you want the formatted diskette to be double-bit density, simply press RETURN; if you want the formatted diskette to be single-bit density, type NO and press RETURN. The system will then print: Double Sided ? To create a double-sided diskette (if you have drives that handle double-sided diskettes), simply press RETURN.
4- 14 1l.... DOUBLE-DENSITY DISK CONTROLLER D- GENERAL DRIVE CHECKOUT The purpose of the General Drive Checkout is to verify that your system is reading from and writing to the diskette properly. Each sector on the diskette is written to and read from a number of times. Various patterns are written on the diskette to allow testing of the head seek mechanism and the read/write head itself. The test is repeated three times. Do not be alarmed if this test seems to take an abnormally long time to finish.
DOUBLE-DENSITY DISK CONTROLLER 4-15 _ _ _ _ _ _ _ _ _ _1 . If you have hard errors, the best approach is to exit this program (type E at the option menu), format another blank diskette, and repeat the entire TEST procedure. If this approach is successful, it is probably because the first diskette had one or more bad sectors, possibly caused by dust. If replacing the diskette corrects the hard errors, continue through the other TEST options and then use "Switch" to restart TEST.
4- 16 1 DOUBLE-DENSITY DISK CONTROLl.ER The first speed to be tested is 30 milliseconds per track. The program will attempt faster step rates of 20, 12, and 6 milliseconds until it has determined your drive's fastest reliable seek time. As it tests, the program will print what speed it is attempting. For each successful pass, TEST will print the message "OK!" to indicate that the drive performs reliably at that speed.
DOUBLE-DENSITY DISK CONTROLLER To begin the alignment procedure, insert the alignment diskette into the drive whose hardware configuration number appears in the message and press RETURN. The program will print: Enter track number <0> At this point, enter the first track number (as directed by the manual provided with the alignment disk) and press RETURN.
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----l15..1 DOUBLE-DENSITY DISK CONTROLLER Service RECALIBRATION You will need the following equipment to calibrate your Disk Controller Board: • A Digital Voltmeter (DVM) with 3-1/2 digit readout. • A calibrated oscilloscope with sweep speeds of 100 ns/cm and 200 ns/cm, and an operating scale of 5 V peak-to-peak. • A Frequency Counter capable of measuring 2.00 MHz. (Optional, but preferred). • HDOS 2.0 modified with INIT or CP/M 2.2.03 with FORMAT software.
5-2 11...-- DOUBLE-DENSITY DISK CONTROLLER VCO BIAS ADJUSTMENT Warm up the Computer for a minimum of 15 minutes with the lid closed. Connect your DVM to test point 1 on the H-/Z-89-37 board; connect the negative lead to ground and the positive lead to test point 1. The reading should be 1.38 to 1.42 V (this is the VCO bias voltage). If you do not obtain the proper voltage, adjust control RI0. Disconnect the DVM.
DOUBLE-DENSITY DISK CONTROLLER Figure 5-1 Z-89-37. Part number HE 181-3614 _ 15..
5-4 1 DOUBLE-DENSITY DISK CONTROLLER VCO CENTER FREQUENCY ADJUSTMENT (WITH OSCILLOSCOPE) Connect the oscilloscope's input lead to test point 2. Set the oscilloscope's sweep to 500 ns/cm. The period of the square wave displayed on the screen should be 493 to 506 ns. If it is not, adjust R17. See Figure 5-2. 500n5 2V . .. .. .. ... . ... ~ II- . ~ ... . ~ ... ... ..... ~ . ~ Figure 5-2 Disconnect the oscilloscope. PRECOMPOSITION ADJUSTMENT Connect the oscilloscope to test point 3.
DOUBLE-DENSITY DISK CONTROLLER __ _ _ _ _ _ _ _ _ _ _ _ _ _ _---JI. fi-5 IN CASE OF DIFFICULTY If your system does not operate properly, make the following checks. PROBLEM POSSIBLE CAUSE Drive access light does not turn on when disk is booted. 1. 2. 3. 4. 5. Check for proper connections of floppy cable inside Computer. Check for proper connections of rear panel extension cable inside Computer. Be sure Z-37 or Z-87 is turned on. Check positions of J1 and J2 on Z-89-37 circuit board.
5-6 1 DOUBLE-DENSITY DISK CONTROLLER DECIMAL TO OCTAL TO HEX TO ASCII CONVERSION I II DEC OCT HEX ASCII 0 1 2 3 4 5 6 7 000 001 002 003 004 005 006 007 00 01 02 03 04 05 06 07 8 9 10 11 12 13 14 15 010 011 012 013 014 015 016 017 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 III IV DEC OCT HEX ASCII DEC OCT HEX NUL SOH STX ETX EaT ENQ ACK BEL 32 33 34 35 36 37 38 39 040 041 042 043 044 045 046 047 20 21 22 23 24 25 26 27 SPACE 64 65 66 67 68 69 70 71 100 101 102 103 104 105 1
16.,1 DOUBLE-DENSITY DISK CONTROLLER Replacement Parts List (Double-density disk controller circuit board part number HE 181-3614.) CIRCUIT Compo No. PART DESCRIPTION NUMBER (..
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~l7 ··1 DOUBLE-DENSITY DISK CONTROLLER Semiconductor Identification Chart INTEGRATED CIRCUITS COMPONENT NUMBER PART NUMBER MAYBE REPLACED WITH U1 HE 443-885 74LS245 U2 HE 443-754 74LS240 IDENTIFICATION
7-21 DOUBLE-DENSITY DISK CONTROLLER Integrated Circuits (Cont'd.) COMPONENT NUMBER PART NUMBER u MAYBE REPLACED WITH IDENTIFICATION INPUTS OUTPUT AD Vee U3 HE 443-912 74LS148 -..INPUTS U4 HE 444-81 * U5 HE 443-745 74LS03P Vee WE RE OUTPUTS ii"OTN A' IN 11 U6 HE 444-82 * 7 AD *Only available from Heath Co.
17--3 DOUBLE-DENSITY DISK CONTROLLER Integrated Circuits (Cont'd.) COMPONENT NUMBER PART NUMBER MAYBE REPLACED WITH U7 HE 443-730 74LS74 U8 HE 443·727 96L02 U9 HE 150-107 LOCO II IDENTIFICATION 16 MHz Ose. RIPPLE CARRY OUTPUT OUTPUTS 15 U10 HE 443-757 74LS161 I CLEAR U11 HE 443·805 74LS273 7 CLOCK C ENABLE -----..
7-4 1_ _--------------DOUBLE-DENSITY DISK CONTROLLER Integrated Circuits (Cont'd.
DOUBLE-DENSITY DISK CONTROLLER C, .....,11 Integrated Circuits (Cont'd) COMPONENT NUMBER PART NUMBER MAYBE REPLACED WITH U16 HE 443-998 WD1691 IDENTIFICATION t::;) o '"s: U17 HE 443-999 74LS624 C' Vee PREAMP ADJ. OPW 17 U18 HE 443-1000 WD2143-03 U19, U20, U21, U22 HE 443-73 7416N U23 HE 442-627 78L05 ~ G:P' '" IN I~ 7..
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DOUBLE.DENSITY DISK. CONTROLLER ~ • Circuit Board X-Ray View NOTE: To find the PART NUMBER of a component for the purpose of ordering a replacement part: • A. Find the circuit component number (Ci0i, Ci04, etc.) on the X-Ray View. B. Locate the same number in the "Circuit Component Number" columns of the "Replacement Parts List." C. Adjacent to the circuit component number, you will find the PART NUMBER and DESCRIPTION which must be supplied when you order a replacement part. __.;...
• Z-89-37 DOUBLE-DENSITY DISK CONTROLLER BOARD Part number HE 181-3614. Shown from the component side.
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