Ricoh B003 Service Manual page 756

4.2.5 SIG4 BOARD
Flash
Reset
Circuit
The SiG4 (Standard ISDN G4) board contains ICCP (ISDN Communication Control
Processor), Flash ROM, DRAM, LAPD controller, CODEC, ISDN interface and
analog interface. The ICCP controls the entire board.
ICCP (ISDN Communication Control Processor)
• 16 bit CPU which controls the entire board
• HDLC control
• Channel select for B channel interface control
CODEC
• A/D, D/A converter for ISDN G3 communication
LAPD Controller
• ISDN layer 1 and LAPD control
ROM
• 512 kB (4 Mbit) Flash ROM for system software storage
DRAM
• 2MB (16 Mbit) DRAM used
SM
CÓPIA NÃO CONTROLADA
DRAM
ROM
SYSTEM BUS
Dch
Bch
ICCP
CODEC
FCU
4-7
CÓPIA NÃO CONTROLADA
SiG4
LAPD ISDN
Controller Interface
Analog I/F
Circuit
MODEM
BOARDS
ISDN
H548D500.WMF
B003/B004/B00/B007