Toshiba T4700CS User manual

T4700CS, T4700CT, T4800CT 1-1
1.1 Features
The Toshiba T4700CS/T4700CT/T4800CT is one of the lightest and most advanced portable
computers available. Utilizing advanced technology and high-speed components, the
T4700CS/T4700CT/T4800CT offers excellent color display legibility, battery operation and
IBM PC/AT compatibility. The T4700CS/T4700CT/T4800CT system unit consists of the
following features:
❑Microprocessor
The T4700CS/T4700CT uses an SL Enhanced Intel 486TMDX2 Microprocessor
(referred to as 486DX2 in this manual) that operates at 50 MHz, 3.3 Volts.
The T4800CT uses an SL Enhanced Intel 486TMDX4 Microprocessor (referred to as
486DX4 in this manual) that operates at 75 MHz, 3.3 Volts.
❑Math co-processor
The T4700CS/T4700CT has a math co-processor which is stored in the 486DX2.
The T4800CT has a math co-processor which is stored in the 486DX4.
❑Cache memory
The T4700CS/T4700CT has an 8 KB cache memory which is stored in the 486DX2.
The T4800CT has an 16-KB cache memory which is stored in the 486DX4.
❑Disk storage
The T4700CS/T4700CT has an internal 200- or 320-Megabyte (MB) Hard Disk Drive
(HDD) with an average access time of 12 milliseconds. A 3.5-inch Floppy Disk Drive
(FDD) supports 2HD floppy disks (1.44 Mbytes) and 2DD floppy disks (720 Kbytes).
The T4800CT has an internal 320 or 500 MB HDD with an average access time of 12
milliseconds. A 3.5-inch FDD supports 2HD floppy disks (1.44 Mbytes) and 2DD
floppy disks (720 Kbytes).
❑Memory
The T4700CS/T4700CT/T4800CT comes standard with 8 MB of CMOS Random
Access Memory (RAM) 3.3 Volts. This includes 640 KB of conventional memory and
7,424 KB of extended memory which can be utilized as expanded memory compatible
with the Lotus/Intel/Microsoft Expanded Memory Specifications (LIM-EMS).

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❑STN color LCD (T4700CS)
A high-resolution 9.5-inch full-color, Supertwist Nematic (STN) color Liquid Crystal
Display (LCD) displays 640x480 pixels with 226,981 colors for both graphics and
characters. The T4700CS internal display controller supports Video Graphics Array
(VGA) functions on the internal display devices.
The T4700CS internal display controller supports Video Graphics Adapter (VGA)
functions on the internal display and Super VGA (SVGA) functions on the external
display.
❑TFT color LCD (T4700CT/T4800CT)
A high-resolution 9.5-inch full-color, Thin Film Transistor (TFT) color LCD displays
640x480 pixels.
The T4700CT/T4800CT internal display controller supports VGA functions on the
internal display and SVGA functions on the external display.
❑Keyboard
An easy-to-use 82/84-key enhanced keyboard with full-size keys and standard spacing
is compatible with IBM standard software.
❑Batteries
The T4700CS/T4700CT/T4800CT has three different batteries: a main battery, a
backup battery, and a Real Time Clock (RTC) battery.
❑Status indicator panel
The T4700CS/T4700CT/T4800CT has a status indicator panel. It is a liquid crystal
display (LCD) panel which displays battery charge indicator and 11 icons indicating
the system status.
❑Memory card slot
The T4700CS/T4700CT/T4800CT has one Toshiba optional memory card slot, which
enables you to install a Toshiba optional memory card.
❑Personal Computer Memory Card International Association (PCMCIA) card slot
The T4700CS/T4700CT/T4800CT has two PCMCIA slots, which enable you to
install a MiNC Toshiba card modem or other industry standard PCMCIA release 2.0
card.

T4700CS, T4700CT, T4800CT 1-3
❑Expansion port
The T4700CS/T4700CT/T4800CT has one unique 150-pin expansion port, which
attaches to a Desk Station IV.
❑PRT/FDD port
T4700CS/T4700CT/T4800CT’s Centronics compatible parallel interface port serves
two purposes. The port can be used to connect a Centronics compatible printer or an
external 5.25-inch floppy disk drive.
❑RS-232C port
The T4700CS/T4700CT/T4800CT has one 9-pin serial interface port.
❑Mouse port
The T4700CS/T4700CT/T4800CT has one 6-pin mouse port on the back that can be
connected to an IBM PS/2 mouse.
❑Keyboard port
The T4700CS/T4700CT/T4800CT has one 6-pin keyboard port on the back that can
be connected to an IBM PS/2 keyboard.
❑Microsoft BallPoint mouse V2.0 with QuickPort connection (BPQP2)
The T4700CS/T4700CT/T4800CT has one BPQP2 port on the right.
❑RGB port
The T4700CS/T4700CT/T4800CT has one 15-pin RGB port on the back that can be
connected to an external video display.
❑Audio ports
• Headphone, standard 3.5 mm diameter miniature stereo jack with
speaker shutoff switch.
Use a headphone with an impedance of 16W.
• Microphone, standard 3.5 mm diameter miniature monaural jack.

1-4 T4700CS, T4700CT, T4800CT
The T4700CS/T4700CT/T4800CT Personal Computer is shown in figure 1-1. The system
configuration is shown in figure 1-2.
Figure 1-1 T4700CS/T4700CT/T4800CT personal computer
Figure 1-2 T4700CS/T4700CT/T4800CT system unit configuration

T4700CS, T4700CT, T4800CT 1-5
1.2 System Unit Block Diagram
Figure 1-3 is a block diagram of the T4700CS/T4700CT/T4800CT system unit.
Figure 1-3 T4700CS/T4700CT/T4800CT system board block diagram

1-6 T4700CS, T4700CT, T4800CT
The T4700CS/T4700CT/T4800CT system board shown in figure 1-3 is composed of the
following major components:
❑ A 486DX2-50 (T4700CS/T4700CT) CPU, which incorporates a math co-
processor and 8 KB cache memory.
A 486DX4-75 (T4800CT) CPU, which incorporates a math co-processor and
16 KB cache memory.
❑The following memory components:
Standard RAM: 8 MB, 32-bit data width (70 ns)
Cache memory: 8 KB (inside a 486DX2-50 CPU)
16 KB (inside a 486DX4-75 CPU)
System, Video, 128 KB (96 KB are used), 8-bit data width
BIOS: A 1-Mbit flash ROM is used (150 ns).
This ROM contains Initial Reliability Test (IRT), Basic Input/
Output System (BIOS), and video BIOS.
Video RAM: 1 MB, 16-bit data width.
Two 256Kx16 bit chips are used.
Memory card: 4, 8, or 16 MB memory card can be installed.
32-bit data width.
❑ Super Integration (SI) T9901, which stores the following components:
•Two Direct Memory Access Controllers (DMAC): 82C37
•Two Programmable Interrupt Controllers (PIC): 82C59
•One Programmable Interval Timer (PIT): 82C54
•One Floppy Disk Controller (FDC): TC8565
•One Serial Input/Output Controller (SIO): TC8570
•One Variable Frequency Oscillator (VFO): TC8568
•One I/O Controller
•One Printer Port Controller
•One Speaker Controller
❑ A Real Time Clock (RTC)
One T9934 chip is used. The T9934 has 128 of bytes memory. Fourteen bytes
memory are used for the calendar and clock. The remaining 114 bytes are used for the
system configuration data.
❑ A Keyboard Controller (KBC)
One M37452M4 chip is used.
This KBC includes the keyboard scan controller and keyboard interface controller.
The KBC controls the internal keyboard, external keyboard port, PS/2 mouse port,
and BPQP2 port.

T4700CS, T4700CT, T4800CT 1-7
❑VGA display controller: WD90C24A (208-pin)
This controller controls internal and external VGA compatible display and external
SVGA compatible display with Analog Digital Converter (DAC). It can display data
on the internal and external display at the same time and operates at 3.3 volts.
.
❑Sound Controller
One AD1848 chip is used. The AD1848 controls the internal sound system.
❑Clock Generator receives 14.31818 MHz (X1) and generates the following frequen-
cies:
•25 MHz for the CPU (CPU operates 50MHz[T4700CS/T4700CT] or
75MHz [T4800CT])
•14.7456 MHz for the COM
•24 MHz for the FDC and VFO
•16 MHz is used for GA
•14.31818 MHz for WD90C24A (for VGA)
OSC (X3) generates 32.768 KHz for RTC.
❑Gate Array
System Controller Gate Array
This gate array has following functions:
•CPU Controller
-SMI Controller
-CPU Clock Controller
•Memory Controller
-DRAM Controller
-Compatible Bus Interface Controller
•Bus Controller
-Compatible Bus Interface Controller
-Compatible Access Controller
-DMAC Controller
-I/O Controller
•Address Latch Controller
-32-Bit to 16-Bit Controller
-Address Latch
-DMA Address Generator
-Refresh Address Generator
•I/O Register
-Compatible I/O Port Register
-Saving the data of the Register (in resume) Controller
-Toshiba Special Register

1-8 T4700CS, T4700CT, T4800CT
•Processing Speed Controller
•Data Latch
•Suspend/Resume Controller
Sub LCD Controller Gate Array
This gate array has following functions:
•Status Indicator Panel Controller
-LCD Segment Flashing Controller
•Internal Communication Controller
-KBC/Power Supply Micro Processor/Main CPU Communication
Controller
-KBC/Power Supply Micro Processor Interrupt Controller
IC Card Controller Gate Array
This gate array has following functions:
•IC Card Controller
-PCMCIA IC Card Controller
-Toshiba Modem Card Controller
•EEPROM (for security) Controller
-KBC-Security-EEPROM Communication Controller
•Others
-KBC Communication Controller
-Disable the PRT/FDD Port, HDD Access Controller
-EEPROM (for BIOS) Access Mode Controller
-Sound System Access Controller

T4700CS, T4700CT, T4800CT 1-9
1.3 3.5-inch Floppy Disk Drive
The T4700CS/T4700CT/T4800CT 3.5-inch Floppy Disk Drive (FDD) is a thin, high-perfor-
mance reliable drive that supports 720-KB (formatted) 2DD and 1.44-MB (formatted) 2HD
3.5-inch floppy disks.
The T4700CS/T4700CT/T4800CT FDD is shown in figure 1-4. The specifications for the
FDD are described in table 1-1.
Figure 1-4 3.5-inch FDD
Table 1-1 3.5-inch FDD specifications
Item 2-MB mode 1-MB mode
Storage capacity (KB)
Unformatted 2,000 1,000
Formatted 1,311 737
Number of heads 2 2
Number of cylinders 80 80
Access time (ms)
Track to track 3 3
Average 181 181
Head settling time 15 15
Recording track density (tpi) 135 135
Data transfer rate (Kbps) 500 250
Rotation speed (rpm) 300 300
Recording method Modified Frequency Modulation (MFM)

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1.4 2.5-inch Hard Disk Drive
The Hard Disk Drive (HDD) is a random access non-volatile storage device. It has a non-
removable 2.5-inch magnetic disk and mini-winchester type magnetic heads.
T4700CS/T4700CT supports the 200 MB and 320 MB. T4800CT supports the 320 MB and
500 MB.
The T4700CS/T4700CT/T4800CT HDD is shown in figure 1-5. Specifications for the HDD
are described in table 1-2.
Figure 1-5 2.5-Inch HDD
Table 1-2 2.5-inch HDD specifications
200 MB 320 MB 500 MB
(MK2224FC) (MK2326FC) (MK2428FC)
Storage capacity (MB)
Formatted 213.0 320.0 524.0
Number of disks 2 3 4
Data heads 4 6 8
Data surfaces 4 6 8
Track per surface 1,560 1,830 1,920
Bytes per sector 512 512 512
Access time (ms)
Track to track 3 3 3
Average 12 12 12
Maximum 25 25 25
Rotation speed (rpm) 4,000 4,200 4,000
Data transfer rate (bps)
To/from media 18.9 to 31.6 M 18.7 to 29.6 M 18.9 to 31.6 M
Interleave 1:1 1:1 1:1
Recording method 1-7 RLL 1-7 RLL 1-7 RLL