Fax Board; Overview; Block Diagram; Function - Konica Minolta bizhub 200 Service Manual

3. Summary of Board functions
3.2

FAX Board

3.2.1

Overview

• This board comes loaded with a G3 modem for communicating Super G3 facsimile com-
munications. Cascade connection of two identical fax boards easily achieves a multi-
port.
3.2.2

Block diagram

MFB3 board I/F
ETCX
Address
Data bus
Control signal
Line monitor signal
3.2.3

Function

A. Modem DSP (MMD5020 V.34 modem)
• A digital signal processor (DSP) and a ROM/RAM are integrated in this modem chip.
• A modem F/W ROM and Boot memory (SRAM) are built in the modem.
• The communication operation conforms to the ITU-T recommendation V.8, V.34, V.17,
V.29, V.27ter and V.21ch2.
• It can be operated at speeds from 33.6 kbps to 2.4 kbps (2.4 kbps steps) and 300 bps.
The basic specification for the recommendation is the same as before.
• It also transmits PB tones when calling PB via Line controller.
• This modem is positioned on the memory map on the MFBS board.
• The analog circuit block following the analog front-end section (AFE) to convert A/D and
D/A are processed in the Line controller.
B. Communication controller (ETCX LSI)
• It possesses an interface for the host (MFB3 board) to access to the modem DSP (data,
address, interruption and CS decoding).
• It possesses a ringer detection function using binary output from the silicone DAA.
• It has a cascade connection function to achieve multi-port.
• It enables multi-port communication by connecting two identical fax boards.
14
MMD5020
(DSP)
TYPE3 I/F
Serial I/F
Theory of Operation Ver. 1.0 Aug. 2005
Si3056 Si3019
Hybrid
DC/AC
Termination
APE
PSTN I/F
SiDAA
External
constant
circuit
TEL I/F
4040T2E611AA