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Information contained in this document is subject to change without notice and does not represent a commitment on the part of Apricot Computers Limited. The software described in this manual is furnished under a license agreement. The software may be used or copied only in accordance with the terms of this agreement.
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All computers in the Apricot LS Pro range are covered. The manual is divided into a number of sections and appendices as described below: 1. Introduction This is a brief overview of the Apricot LS Pro which describes the options and major components of the system. 2. System Unit This section describes the system unit: it also includes disassembly instructions for servicing and replacing major components of the system.
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8237 DMA controller 8254 System timers 8259 Interrupt controllers 82596 Ethernet coprocessor VLSI VL82C311 (SCAMP) AT chipset Cyrix 486SLC Cirrus CL-GD542X video controller National Semiconductor NS16450 Serial communications controller Hitachi MC146818 Real time clock 2 LS PRO HARDWARE TECHNICAL REFERENCE...
General ........3/15 Quantum ProDrive Drive formats ......3/15 LPS240AT ......... 4/12 3.7 Hard disk interface ... 3/16 Quantum ProDrive General ........3/16 LPS525AT ......... 4/13 Interface signal descriptions . 3/16 IDE interface ......4/14 LS PRO HARDWARE TECHNICAL REFERENCE 1...
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Business audio ......5/17 Floppy disk controller ... 5/17 Parallel port controller ..5/18 Video DAC ......5/19 VGA registers ......5/20 CL-GD542X Extension registers ........5/25 APPENDICES Specifications Revision C system board Error beep codes INDEX 2 LS PRO HARDWARE TECHNICAL REFERENCE...
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Introduction Contents INTRODUCTION General ........1/2 Keyboard ........1/3 Variants ........1/2 Monitors ........1/3 System unit ......... 1/3 Expansion ........1/4 LS PRO HARDWARE TECHNICAL REFERENCE 1/1...
Introduction General The Apricot LS Pro family is a range of ultra-compact IBM compatible computers which can be used as a personal computer, a network workstation or a high resolution graphics workstation. The main features of the system are: • 80386SX or 486SLC microprocessor operating at up to 33MHz.
The on-board VGA controller also supports high resolution video modes. To take advantage of the higher resolution video modes an SVGA or EVGA monitor must be used. Video drivers for popular software packages are available. LS PRO HARDWARE TECHNICAL REFERENCE 1/3...
PROCESSOR; MEMORY; VIDEO ADAPTER ETHERNET CONTROLLER; SERIAL PORT PARALLEL PORT; LOC TECHNOLOGY SECURITY FLOPPY DISK CONTROLLER; HARD DISK CONNECTOR; KEYBOARD AND MOUSE PORTS; HARD DISK DRIVE BUSINESS AUDIO. FLOPPY DISK DRIVE KEYBOARD MOUSE 1/4 LS PRO HARDWARE TECHNICAL REFERENCE...
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.......... 2/9 Ethernet ........ 2/20 Removing the fan ....2/10 Serial port ......2/21 Removing the power Parallel port ......2/22 supply ........2/11 Keyboard/mouse Removing a Token-Ring connectors ......2/22 module ........2/11 LS PRO HARDWARE TECHNICAL REFERENCE 2/1...
PAIR ETHERNET LOCK VIDEO THIN PORT ETHERNET THICK SERIAL POWER PORT ETHERNET/ PORT TOKEN RING PORT Illustrations and pinouts of the connectors on the rear panel are given at the rear of this section. 2/2 LS PRO HARDWARE TECHNICAL REFERENCE...
Dismantling and re-assembly The LS Pro range has been designed to meet international EMI and safety standards. Warnings and To ensure safety and continued compliance with these standards, observe the cautions following precautions.
Connector Label Parallel port Token ring module PL9 and PL16 Hard disk drive power PL12 Thick Ethernet PL13 System board power PL15 Hard disk drive control PL17 Floppy disk drive PL18 Loudspeaker PL40 2/4 LS PRO HARDWARE TECHNICAL REFERENCE...
The cover is located by a ledge at top cover the front and lugs on the sides and at the rear. Two thumbscrews in the rear panel secure the cover. LS PRO HARDWARE TECHNICAL REFERENCE 2/5...
SECURING LUGS SECURING CLIPS 1. Remove the system unit top cover. 2. Release the two retaining latches. On releasing the latches, the system board metalwork will spring up slightly. 2/6 LS PRO HARDWARE TECHNICAL REFERENCE...
LEDs. Removing the The floppy drive is mounted in the metalwork above the system board. floppy drive Two variants of metalwork have been used, they are both shown in the illustration below. LS PRO HARDWARE TECHNICAL REFERENCE 2/7...
5. An earth cable connects the power supply to the metalwork. Gently lift the metalwork and carefully turn it over. 6. Remove the screw which secures the cable to the metalwork and lift the metalwork clear. 2/8 LS PRO HARDWARE TECHNICAL REFERENCE...
2. Disconnect the hard disk drive power and signal cables from the system board. Warning Do not attempt to disconnect the cables from the drive with the drive still in the system unit. Attempting to do so will damage the drive circuit board. LS PRO HARDWARE TECHNICAL REFERENCE 2/9...
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4. Replacement is simply the reverse of removal. Make sure that you replace the fan in the same orientation as it was before removal, and that the fan power cable is secured to the fan with a cable tie. 2/10 LS PRO HARDWARE TECHNICAL REFERENCE...
1. Remove the system board metalwork. 2. Remove the screw in the rear panel of the system unit, to the right of the Token- Ring connector. TOKEN RING CONNECTOR SECURING SCREW LS PRO HARDWARE TECHNICAL REFERENCE 2/11...
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Check that the connectors are correctly aligned, then gently insert the module. Warning Take care not to exert undue pressure when inserting the module. 2/12 LS PRO HARDWARE TECHNICAL REFERENCE...
4. Remove the seven screws which secure the system board. 5. Remove the screwlocks that secure the video and serial port connectors. 6. Remove the lock nut on the thin Ethernet connector. 7. Carefully lift the system board clear of the system unit. LS PRO HARDWARE TECHNICAL REFERENCE 2/13...
1. Remove the system unit top cover, system board metalwork, hard disk drive, power supply metalwork, fan, power supply and system board. Warning During the following instructions do not apply excessive pressure or the linkage may be deformed or the plastics break. 2/14 LS PRO HARDWARE TECHNICAL REFERENCE...
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Do not force the linkage into place. RFI screening tray The LS Pro system unit base is fitted with a metal RFI screening tray and a plastic and insulation insulation sheet during manufacture.
RAM is to install an 8 Mbyte upgrade in bank 2 and leave the other bank (or banks) empty. This configuration disables the RAM soldered to the system board. 2. When banks 2 and 3 are both occupied by 8 Mbyte upgrades the RAM soldered to the system board is disabled. 2/16 LS PRO HARDWARE TECHNICAL REFERENCE...
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2. Taking care to avoid touching any of the components on the SIMM grip the top corners of the SIMM between thumb and first finger and carefully pull the SIMM out of the socket. 3. Repeat steps 1 and 2 for the other SIMM(s) affected. LS PRO HARDWARE TECHNICAL REFERENCE 2/17...
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7. Rotate the SIMM into the vertical position by pushing gently on the top corners. 8. If the SIMM is properly located the SIMM should remain in position held by the securing clips, and with a small plastic lug through the holes on either side of the SIMM. 2/18 LS PRO HARDWARE TECHNICAL REFERENCE...
80387SX in the socket with the positioning guide at pin 1 making sure that you do not bend or otherwise damage the pins. Note The 80387SX only fits in one orientation. Do not use excessive force or damage may occur. 5. Reassemble the system. LS PRO HARDWARE TECHNICAL REFERENCE 2/19...
Signal Collision presence shield Collision presence (+ve) Transmit (+ve) Receive shield Receive (+ve) Power return Reserved (+ve) Reserved shield Collision presence (-ve) Transmit (-ve) Transmit shield Receive (-ve) Power Power shield Reserved (-ve) 2/20 LS PRO HARDWARE TECHNICAL REFERENCE...
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Transmit data (COM2) Receive data (COM2) Request to send (COM2) Data terminal ready (COM1) Ring indicate(COM1) All other pins are not connected. Note The Rev C system board does not provide the COM2 signals. LS PRO HARDWARE TECHNICAL REFERENCE 2/21...
Data bit 6 Ground Data bit 7 Ground Ack- Ground Busy Ground Ground SLCT Keyboard/mouse The keyboard and mouse connectors are miniature 6-pin connectors DIN connectors. Signal name Data Reserved Ground +5Vdc Clock Reserved 2/22 LS PRO HARDWARE TECHNICAL REFERENCE...
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(RAM) ........3/10 System board power Real time clock (RTC)RAM . 3/11 connector ......3/22 Contents of RTC RAM ..3/11 Battery jumper ....3/22 3.5 Video adapter .....3/14 General ........3/14 Video controllers ... 3/15 LS PRO HARDWARE TECHNICAL REFERENCE 3/1...
This section describes the LS Pro system board and the operation of its processing system and interface circuits. The LS Pro range uses a highly integrated, IBM AT compatible system board. In addition to standard features, the LS Pro system board provides: Ethernet interface, business audio subsystem, LOC Technology security subsystem and a mouse port.
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CONNECTOR PARALLEL PORT SOCKET PERIPHERALS CONTROLLER VIDEO TOKEN RING THICK CONTROLLER MODULE ETHERNET CONNECTOR SOCKET KEYBOARD CONTROLLER BATTERY POWER CONNECTOR SIMM SOCKETS 80387SX SOCKET R A M AUDIO ETHERNET CONTROLLER SCAMP FLOPPY PROCESSOR CONTROLLER LS PRO HARDWARE TECHNICAL REFERENCE 3/3...
The block diagram is a functional description of the system board and does not identify specific chips. The LS Pro system board uses highly integrated components, reducing the chip count and the system board area, and increasing reliability. The VLSI SCAMP chipset integrates much of the standard AT system board peripheral logic onto a single chip.
In the virtual 8086 mode the 80386SX/486SLC creates one or more 8086 environments within its protected multitask environment. This allows multiple 8086 tasks or a mixture of 8086 and 80286/80386 tasks to be executed concurrently. LS PRO HARDWARE TECHNICAL REFERENCE 3/5...
System Board SCAMP The LS Pro system board is based on a VLSI VL82C311 single chip AT compatible chipset. The VL82C311 integrates the following standard AT system board peripheral logic in a single QFP package: • two 8237A DMA controllers •...
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Digital audio IRQ3 Reserved IRQ4 Serial port IRQ5 Reserved IRQ6 Floppy disk controller IRQ7 Parallel port Note IRQ0 and IRQ13 are both used inside the SCAMP chip. Neither emerges for use on the system board. LS PRO HARDWARE TECHNICAL REFERENCE 3/7...
24-bit address. The bits 0-7 are taken directly from the 8237A address outputs, bits 8-15 are latched from the 8237A data outputs while bits 16-24 are from the appropriate DMA page register. 3/8 LS PRO HARDWARE TECHNICAL REFERENCE...
A refresh request puts the processor into hold and accesses memory via a DMA type operation. Sound output The sound output may be set to give the output frequency required. To enable the output bit 0 of Port B (I/O 0061h) must be set to 1. LS PRO HARDWARE TECHNICAL REFERENCE 3/9...
RAM available with each. Bank System board Upgrade to (Mbytes) capacity (Mbytes) (Mbytes) Note When banks 2 and 3 are both occupied by 8 Mbyte upgrades the RAM soldered to the system board is disabled. 3/10 LS PRO HARDWARE TECHNICAL REFERENCE...
(see also Apricot byte 2Bh) Reserved Apricot access rights Fixed disk drive type Floppy/Token-Ring autodetect Power on password Hard disk autodetect Equipment byte 38-3E Power on password Base memory (low byte) Byte checksum of bytes 38-3E LS PRO HARDWARE TECHNICAL REFERENCE 3/11...
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00h = VGA 01h = Not used (40 column colour) 02h = Not used (80 column colour) 03h = Not used (Monochrome) Reserved 1 = 80387 installed 1 = Diskette drive available for boot 3/12 LS PRO HARDWARE TECHNICAL REFERENCE...
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1 = cache enabled (see 2Bh) Reserved Reserved Access rights 1 = Setup access right enabled 1 = Floppy boot right enabled Reserved Floppy/ 1 = Token-Ring present Token-Ring 1 = Floppy drive present autodetect LS PRO HARDWARE TECHNICAL REFERENCE 3/13...
VIDEO ADAPTER General The video adapter on the LS Pro system board is based on either a Cirrus Logic CL-GD5422 or 5426 chip. These chips contain all the elements of a VGA controller, except display memory, providing 100% compatibility with the IBM VGA standard.
In this implementation a single 1.44 Mbyte floppy drive can be fitted. 720k and 1.44M diskettes are supported for both single and multithread operations. The default precompensation is 125 nanoseconds and is present for all cylinders. LS PRO HARDWARE TECHNICAL REFERENCE 3/15...
HARD DISK INTERFACE General The hard disk drive connector which is fitted on the LS Pro system board is an IDE connector which conforms to the ATA interface standard. The hard disk drive is accessed via a group of I/O ports at 01F0-01F7h. The function of each port is given in section 5.
When either of the divisor latches is loaded, a 16-bit baud counter is immediately loaded. This prevents long counts on the first load. LS PRO HARDWARE TECHNICAL REFERENCE 3/17...
The significance of port 0064h is described in section 5. Keyboard password security The 8042 provides a password security mechanism. Three commands are available regarding password operation: Test Password Installed Load Security Enable Security 3/18 LS PRO HARDWARE TECHNICAL REFERENCE...
The system board is fitted with a LOC Technology security subsystem. This subsystem allows Apricot LOC Technology software to control access to data and facilities. When Apricot LOC Technology is not in use the security hardware is passive and has no effect on the system.
82503 automatically corrects the error by reversing the signals internally. 7997 The Ethernet transceiver chip acts as the interface between thick and thin Ethernet cabling standards, implementing the IEEE802.3 10BASE2 standard. 3/20 LS PRO HARDWARE TECHNICAL REFERENCE...
System Board 3.12 APRICOT BUSINESS AUDIO The Apricot Business Audio subsystem integrated on the LS Pro system board is based on a Yamaha YMZ263 chip. It offers two channels each of which can be independently configured to either playback or record.
CMOS RAM is discharged. The jumper is identified in the illustration on page 2/5, and instructions on accessing the system board are given in section 2. 3/22 LS PRO HARDWARE TECHNICAL REFERENCE...
PCB provides power for the system unit fan. Warning The auxiliary AC outlet must only be used to power monitors approved by Apricot. The power supply on/off switch acts as the system on/off switch and is operated from the front panel via a mechanical linkage.
Power good MONITORS Introduction Apricot supplies 14" colour SVGA, and 14" and 17" colour EVGA monitors. All Apricot SVGA and EVGA monitors described here are low emission monitors which are compliant with the MPR2 radiation legislation. These monitors are fully compatible with the adapter on the system board and may be used in any standard VGA display mode.
Video signal All the Apricot monitors can be used with any computer which supplies an analogue video signal with a 31.47kHz horizontal scan frequency. Because the monitors accept analogue video signals, an infinitely variable range of gray shades/colours may be displayed.
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This control adjusts the overall height of the on screen image, and only affects the 800x600 display mode. Horizontal phase This control adjusts the horizontal position of the display area, and only affects the 800x600 and 1024x768 display modes. LS PRO HARDWARE TECHNICAL REFERENCE 4/5...
Avoid setting the brightness and contrast controls for an excessively bright display. If such a display is left on the screen for an extended period the screen phosphor may be damaged. On the left side of the monitor are horizontal and vertical size and position controls. 4/6 LS PRO HARDWARE TECHNICAL REFERENCE...
800x600 and 1024x768 resolutions. External controls On the right side of the monitor are the power switch and brightness and contrast controls. These are shown in the following illustration. BRIGHTNESS POWER CONTRAST SWITCH CONTROL CONTROL LS PRO HARDWARE TECHNICAL REFERENCE 4/7...
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This control adjusts the horizontal position of the display area. Vertical size This control adjusts the overall height of the on screen image. Vertical position This control adjusts the vertical position of the display area. 4/8 LS PRO HARDWARE TECHNICAL REFERENCE...
01F9h. The function of these registers and their bit significance is given in section 5. Quantum ProDrive ELS The 85, 127 and 170 Mbyte hard disk drives that may be fitted in the LS Pro range are from the Quantum ProDrive ELS range. The drives have nominal access times of 17mS and can transfer data at up to 4.0 Mbytes per second.
The three jumpers are labelled DS (Drive select), CS (Cable select) and SP (Slave present). The DS jumper must be fitted and the CS and SP jumpers not, in order for the drive to function in an LS Pro. Drive formats...
Peripheral items Maxtor 7213A The 213 Mbyte hard disk drive that may be fitted in the LS Pro range is a Maxtor 7213A. It has a nominal access time of 15mS and can transfer data at up to 8.0 Mbytes per second.
Quantum ProDrive LPS 240AT The 240 Mbyte hard disk drive that may be fitted in the LS Pro range is a Quantum ProDrive LPS 240AT. It has a nominal access time of 16mS and can transfer data at up to 5.0 Mbytes per second.
Full information on configuring Discache is given in the Quantum specification. Quantum LPS525A The 525 Mbyte hard disk drive that may be fitted in the LS Pro range is a Quantum LPS525A. It has a nominal access time of 10mS and can transfer data at up to 5 Mbytes per second.
Peripheral items The three jumpers are labelled DS (Drive select), CS (Cable select) and SP (Slave present). In the LS Pro application the DS jumper must be fitted and the CS and SS jumpers not. Warning None of the other jumpers are used in this application. If any of the other jumpers are installed the drive will not function correctly.
Informs the system board that the drive data register has been enabled and the drive is prepared to perform a 16-bit I/O transfer. Host ADDR 0-2 These lines are used to select registers on the drive. LS PRO HARDWARE TECHNICAL REFERENCE 4/15...
ADDR0 host data 14 host ADDR2 host data 0 host data 15 ground ground The pin layout of the connector. Power connector Function +12 Volts ground (for +12V) ground (for +5V) +5 Volts 4/16 LS PRO HARDWARE TECHNICAL REFERENCE...
FLOPPY DRIVE Description The floppy disk drive fitted in the LS Pro range is a 3.5", high density double-sided, one inch high unit. The drive can read and write 3.5" discs with a formatted capacity of either 1.44Mbytes or 720 kbytes. The drive has a constant disk rotation speed of 300 rpm.
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A low pulse on this input will cause the read/write head to move to the next track. The direction of movement is determined by the direction input at the end of the step pulse. 4/18 LS PRO HARDWARE TECHNICAL REFERENCE...
The following illustration shows the layout of the keys and the key legends on the UK keyboard. apricot Print Pause Scroll Scrn Lock SysRq Break £ & Home Page Insert Lock Page Delete Down Home Pg Up Caps Lock < > Pg Dn Enter Ctrl Alt Gr Ctri LS PRO HARDWARE TECHNICAL REFERENCE 4/19...
Echo (EEh) This is sent in response to an echo command from the system unit. Self-test pass (AAh) This code is sent to the system unit if the keyboard RAM and ROM self-test is passed. 4/20 LS PRO HARDWARE TECHNICAL REFERENCE...
When the keyboard receives any of these commands, it sends an ACKnowledge (FAh) response. If the data is incorrectly received the keyboard sends a RESEND (FEh) request. The use and formats of these commands is described in the following paragraphs. LS PRO HARDWARE TECHNICAL REFERENCE 4/21...
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The delay before the typematic operation comes into effect is shown in the table below: Delay 250mS 500mS 750mS 1000mS Enable (F4h) The keyboard responds with an ACK, clears its output buffer, and enables key scanning and keycode transmission. 4/22 LS PRO HARDWARE TECHNICAL REFERENCE...
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The codes are listed in the following table: Scan code set 1 Make Break Make Break Number Code Code Number Code Code E0 38 E0 B8 E0 1D E0 9D E0 35 E0 B5 E0 1C E0 9C 4/24 LS PRO HARDWARE TECHNICAL REFERENCE...
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E0 D0 D0 2A E0 AA E0 49 E0 C9 E0 2A E0 AA E0 51 E0 D1 E0 2A E0 AA E0 4D E0 CD E0 2A E0 AA E0 35 E0 B5 E0 2A LS PRO HARDWARE TECHNICAL REFERENCE 4/25...
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E0 F0 7C E0 7A E0 F0 7A Alt key active E0 74 E0 F0 74 F0 84 Ctrl key active E0 7E E0 This key does F0 7E not have a break code LS PRO HARDWARE TECHNICAL REFERENCE 4/27...
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F0 33 Typematic F0 6B Make only F0 3B Typematic F0 69 Make only F0 42 Typematic F0 77 Make only F0 4B Typematic F0 75 Make only F0 4C Typematic F0 73 Make only 4/28 LS PRO HARDWARE TECHNICAL REFERENCE...
F0 17 Make only Connector The keyboard is connected to the system unit via a 6-pin miniature DIN connector. The pinout and connector details are given below. Signal name Data Reserved Ground +5Vdc Clock Reserved LS PRO HARDWARE TECHNICAL REFERENCE 4/29...
KeyLOC CARD The KeyLOC card is a credit card sized unit which is used in conjunction with the Apricot LOC Technology software to control access to the computer and the data stored on it. The KeyLOC card consists of a plastic case and a small circuit board. The plastic case is in two halves and contains the circuit board and three small batteries.
The SETUP utility allows BIOS shadowing to be enabled or disabled. If shadowing is enabled the BIOS on the system board is copied into RAM where it can be accessed faster. A more detailed description of the region between 768k and 1M (0C0000h and 100000h) is given over. 5/2 LS PRO HARDWARE TECHNICAL REFERENCE...
This often allows DOS to make better use of the available space. Note The Rev C system board has a slightly different memory map, refer to Appendix B for details. LS PRO HARDWARE TECHNICAL REFERENCE 5/3...
Memory and I/O Usage I/O SPACE The table below shows the general use of I/O space on the LS Pro system board. The pages which follow describe in more detail specific ports and groups of ports. Addresses (hex) Device 0000-000F...
Command/status When the system reads I/O location 0064h it receives information about the status of port the controller. When the system writes to I/O location 0064h the byte is interpreted as a command. 5/6 LS PRO HARDWARE TECHNICAL REFERENCE...
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Bit 7 Reserved. Read A read from port 0064h has the following significance. output buffer full input buffer full system flag command/data inhibit switch reserved general timeout parity error LS PRO HARDWARE TECHNICAL REFERENCE 5/7...
This bit reflects the condition of the I/O check latch. If the bit is set to 1 an I/O check has occurred. Bit 7 This bit reflects the condition of the Parity check latch. If the bit is set to 1 a Parity check has occurred. 5/8 LS PRO HARDWARE TECHNICAL REFERENCE...
K (low byte) memory size in K (high byte) expanded memory size in K (low byte) expanded memory size in K (high byte) 19h-31h reserved 32h-33h configuration CRC 34h-36h reserved date century 38h-3Eh reserved checksum LS PRO HARDWARE TECHNICAL REFERENCE 5/9...
36 mapping registers through the two data ports. For further data ports information on EMS refer to the LIM 4.0 specification. The SCAMP EMS system is configured using the EMS configuration registers. 5/10 LS PRO HARDWARE TECHNICAL REFERENCE...
D0000-DFFFFh segment access control E0000-FFFFFh segment access control Reserved Miscellaneous control ROM and DMA control Bus control Apricot ports A block of 16 ports between 0120h and 012Fh are reserved for Apricot specific functions. Port Function LAN LED 1.6 Mbyte floppy reserved...
1 4Mbps is selected. Bit 2 This bit selects between 8 and 16-bit modes. When set to 0 8-bit operation is selected, when set to 1 16-bit is selected. 5/12 LS PRO HARDWARE TECHNICAL REFERENCE...
When it is set high the LED is not lit. Bits 6,7 Reserved. Note The function of this port is different on Rev C system boards. Refer to Appendix B for further information. LS PRO HARDWARE TECHNICAL REFERENCE 5/13...
03FE 02FE Modem status register 03FF 02FF Scratch register The registers are described in detail in the manufacturers data sheets. Note Rev C system boards are not fitted with the second serial port (COM2). 5/14 LS PRO HARDWARE TECHNICAL REFERENCE...
Memory and I/O Usage Ethernet controller The Ethernet controller on the LS Pro system board uses a block of 17 I/O ports from 0300h to 0310h. Port Function 82596 PORT address 0301-0303 reserved 82596 CA address 0305-0307 reserved 0308-030F Ethernet ID PROM...
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0 to bit 0 of 310h write to port 08Eh write a 1 to bit 0 of 310h write to port 08Eh write a 0 to bit 0 of 310h write to port 08Eh Bits 1-7 Reserved. 5/16 LS PRO HARDWARE TECHNICAL REFERENCE...
Memory and I/O Usage Business audio The Apricot business audio subsystem occupies a block of 8 ports from 0388h to 038Fh. Port Function 0388-038B reserved 038C Address 038D channel 0 data 038E reserved 038F channel 1 data The following descriptions are brief outlines of the function of the ports. A full description is given in the manufacturers data sheet.
When this bit is set to 0 the printer has received a character and is ready to accept another. Bit 7 This bit represents the state of the BUSY signal. When the signal is active the printer is busy and cannot accept data. 5/18 LS PRO HARDWARE TECHNICAL REFERENCE...
DAC state register 03C7 Pixel address (read mode) 03C8 Pixel address (write mode) 03C9 Pixel data register These registers comply with the VGA standard. They are described in detail in the manufacturers data sheet. LS PRO HARDWARE TECHNICAL REFERENCE 5/19...
The groups of registers are described in the following sections. There are several pairs of registers an index register and a data register. In these cases the index register is a pointer to a number of other registers which are accessed via the accompanying data register. 5/20 LS PRO HARDWARE TECHNICAL REFERENCE...
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The following table shows the index and the registers that are accessed via the index. Register Index Reset Clocking mode Map mask Character map select Memory mode These are standard VGA registers and are not described in further detail here. LS PRO HARDWARE TECHNICAL REFERENCE 5/21...
Vertical retrace end Vertical display enable end Offset Underline location Start vertical blank End vertical blank CRTC mode control Line compare These are standard VGA registers and are not described in further detail here. 5/22 LS PRO HARDWARE TECHNICAL REFERENCE...
Each colour code is translated by a palette register into video signals to drive the monitor. The attribute controller registers are addressed by a single I/O port address. LS PRO HARDWARE TECHNICAL REFERENCE 5/23...
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The following table shows the index values and the registers that are accessed by them: Register Index Palette 00h to 0Fh Attribute mode control Overscan control Colour plane enable Horizontal pixel panning Colour select These are standard VGA registers and are not described in further detail here. 5/24 LS PRO HARDWARE TECHNICAL REFERENCE...
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Signature generator result (low byte) Signature generator result (high byte) VCLK0-3 denominator and post-scalar value 1B-1E BIOS ROM write enable and MCLK select * indicates that the register is present in the CL-GD5426, but not the CL-GD5422. LS PRO HARDWARE TECHNICAL REFERENCE 5/25...
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VGA standard. Note Revision C of the LS Pro system board is equipped with a CL-GD5410 video controller. This uses a different set of extension registers. Refer to Appendix B for further information.
HiVision 17" Low Emission multi sync Width ..........................405 mm Height ..........................370 mm Depth ..........................480 mm Weight ..........................25.9 kg Resolution ......................1024x768 max Size ............................17" Viewable ..........................16" Pitch ..........................0.26mm LS PRO HARDWARE TECHNICAL REFERENCE A/1...
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Width .......................... 101.6 mm Depth .......................... 150.0 mm Weight ..........................425 g Rotational speed ......................300 rpm Track density ......................... 135 TPI Cylinders ..........................80 Tracks ............................. 160 R/W heads ..........................2 Encoding Method ......................MFM A/2 LS PRO HARDWARE TECHNICAL REFERENCE...
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Seek error rate ..................< 1 per 10 seeks Physical Rotation speed ......................3663rpm Recording density ....................38,600 bpi Track density ........................ 1800 tpi Cylinders ..........................1528 Disks ............................1/2 Tracks ......................3056/4584/6112 Heads ........................... 2/3/4 Capacity (formatted) ................85/127/170 Mbytes LS PRO HARDWARE TECHNICAL REFERENCE A/3...
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Capacity (formatted) ..................... 200Mbytes Quantum LPS 240AT Height ..........................25.4mm Depth ........................... 146.2mm Width ........................... 101.6mm Weight ..........................0.48 Kg Environmental Ambient temperature Operating ........................5 to 55 °C Non-operating ..................... -40 to 70 °C A/4 LS PRO HARDWARE TECHNICAL REFERENCE...
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Disk to Buffer .................... 3.8 Mbytes/second Seek time (ms) Average............................. 17 Track to track ........................... 4 Full stroke ..........................30 Quantum LPS525AL Height ..........................25.4mm Depth ..........................146mm Width ........................... 101.6mm Weight ..........................0.5 Kg LS PRO HARDWARE TECHNICAL REFERENCE A/5...
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Disks ............................3 Tracks ..........................14,688 Heads ............................6 Capacity (unformatted) ....................525 MB Seek time (ms) Average............................. 10 Track to track ........................... 3 Full stroke ..........................18 Maximum data To AT-bus....................5.0 Mbytes/second transfer rates A/6 LS PRO HARDWARE TECHNICAL REFERENCE...
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Revision C system board This manual describes the LS Pro fitted with a Revision D system board. During the first eight months of production the LS Pro range was fitted with Revision C system boards. This Appendix helps you identify which revision of system board you have, and describes the differences between revisions C and D.
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Revision C system board CL-GD5410 The video adapter on revision C of the LS Pro system board is based on a Cirrus Logic CL-GD5410 chip. The CL-GD5410 contains all the elements of a VGA controller, except display memory, providing 100% compatibility with the IBM VGA standard.
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All the code in the region E0000h to EFFFFh region is used only at boot. Thus with the option ROM socket empty the region from C0000h to EFFFFh is available as DOS UMB space. LS PRO HARDWARE TECHNICAL REFERENCE B/3...
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Revision C system board I/O registers The function of two of the Apricot specific I/O ports are different on the revision C system board. The two ports are 121h and 12Ch. On revision C of the system board, port 121h is used to control the diagnostic LED on the system board.
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If a blank screen is obtained, check that power is applied to both the system unit and monitor. Check that all cables are properly connected and that the system is properly configured. LS PRO HARDWARE TECHNICAL REFERENCE C/1...
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Error messages which appear on the screen are in text form, not error codes. The appropriate action can then be taken. For example: Error message Not a boot diskette - strike F1 to retry boot Action Insert correct disk and reboot LS PRO HARDWARE TECHNICAL REFERENCE C/3...