Toshiba Libretto 50CT/70CT Manual

1-iiLibretto 50CT/70CT Maintenance Manual 

Libretto 50CT/70CT Maintenance Manual1-iiiTable of Contents1.1  Features.......................................................................................................................1-1
1.2  System Unit Block Diagram.........................................................................................1-4
1.3  3.5-inch External FDD (Option)..................................................................................1-7
1.4  2.5-inch...

1-ivLibretto 50CT/70CT Maintenance ManualTable 1-5  FL inverter board specifications.......................................................................1-11
Table 1-6  Power supply board output rating....................................................................1-12
Table 1-7  Battery specifications.......................................................................................1-13
Table 1-8  Time required for quick...

1  Hardware Overview1.1  FeaturesLibretto 50CT/70CT Maintenance Manual1-11 
1.1 Features
The Libretto 50CT/70CT uses Toshiba’s advanced Large Scale Integration (LSI) and
Complementary Metal-Oxide Semiconductor (CMOS) technology extensively to provide
compact size, minimum weight, low power usage, and high reliability. The following features
and benefits are incorporated:qMicroprocessor
The Libretto 50CT has a 64-bit microprocessor, Intel Pentium processor running at a
clock speed of 75MHz.
*The Libretto...

1.1  Features1  Hardware Overview1-2Libretto 50CT/70CT Maintenance Manualq Parallel port
A Centronics compatible parallel port on the I/O adapter enables connection of a
printer or other parallel device and supports the Extended Capabilities Port (ECP)
conforming to IEEE-1284.
q Serial port
A standard, 9-pin, serial port only on the I/O adapter enables connection of such serial
devices as a serial printer, mouse, or modem. A Universal Asynchronous
Receiver/Transmitter (UART) is 16550A equivalent.
q...

1  Hardware Overview1.1  FeaturesLibretto 50CT/70CT Maintenance Manual1-3The front of the computer is shown in Figure 1-1.Figure 1-1  Front of the computer
The system unit configuration is shown in Figure 1-2.Figure 1-2  System unit configuration 

1.2  System Unit Block Diagram1  Hardware Overview1-4Libretto 50CT/70CT Maintenance Manual1.2 System Unit Block Diagram
Figure 1-3 is a block diagram of the system unit.Figure 1-3  System unit block diagram 

1  Hardware Overview1.2  System Unit Block DiagramLibretto 50CT/70CT Maintenance Manual1-5The system unit is composed of the following major components:q Microprocessor
Libretto 50CT:  Intel 75 MHz Pentium processor operates at 2.9/3.3 volts and
incorporates the math co-processor and 16 KB cache memory.
*Libretto 70CT:  Intel 120 MHz Pentium processor with MMX technology operates
at 2.9/3.3 volts and incorporates the math co-processor and 16 KB cache memory.
q Standard RAM
· 16 MB, eight 1M x 16-bit EDO...

1.2  System Unit Block Diagram1  Hardware Overview1-6Libretto 50CT/70CT Maintenance Manualq System Controller Gate Array
This gate array has the following functions:
· Two PICs:82C59 equivalent
· Two UARTs:16550A equivalent (one SIO is used for SIR)
· One PIT:82C54 equivalent
· One RTC:T9934 equivalent
· Two DMACs:82C37 equivalent
· I/O port decode
· SIO port control
· Parallel (ECP) port control
· Speaker control
· Power supply microprocessor interface
· PnP support
· CPU control
- SMI control
- Clock...

1  Hardware Overview1.2  System Unit Block DiagramLibretto 50CT/70CT Maintenance Manual1-7q Internal Pointing Stick Controller (IPSC)
Provides simultaneous control of both an AccuPoint and a PS/2 mouse.
q Sound Controller
The Libretto 50CT uses one OPL3-SA2 that incorporates: OPL3 FM synthesizer,
Digital Analog Converter (DAC), and MPU401 MIDI interface.
*The Libretto 70CT uses one OPL3-SA3 that incorporates: OPL3 FM synthesizer,
Digital Analog Converter (DAC), and MPU401 MIDI interface.