Toshiba Satellite M20 Maintenance Manual page 24

1 Hardware Overview
• EC
− Power supply sequence control
− Thermal control
− LED control
− Beep control
− Device ON/OFF
− Cooling fan speed control
− Universal I/O port
− Dock power supply control
− Battery capacity check
− Flash memory reprogramming function
− EC access interface
− I2C communication control
−
RS-232C driver
• MAX3243
− Conversion of signal levels for communication with an external device
2
Battery E PROM
• 24C02 equivalent (128 words x 16 bits, I2C interface) integrated in the battery
pack
− Storing records of battery use
Clock Generator
• ICS950810A
− Generating the clock signal required for the system
−
Modem Controller
• Built-in MDC card with XircomLucent Mars3+SiDAA
• Functions of the modem controller:
− Digital signal conductor protection
− Ring wake-up support
− Communication codes supported:
For data communication:
1-10
V.90 (56K bps) data communication control
V.32 bis (14.4K, 12K, 9600)
V.22 bis (2400, 1200)
V.22 (1200)
V.23 (1200, 600, 75)
V.21 (300)
1.2 System Unit Block Diagram
Satellite M20 Maintenance Manual