Comtech EF Data SMS-458B - Manual (Page 76)

SMS-458B Modem Protection Switch Revision 2
Theory of Operation MN/SMS458B.IOM
4–16
4.3 Address Decoder/Driver
4.3.1 General
The address decoder/driver is a 10.5 x 3.5 inches module (Figure 4-4) that fits into
slot 4 of the front-upper section of the switch chassis. Its functions include:
• Address decoding of the external address bus
• External data bus buffering
• Serial communications interface
• Modem fault interface
• Fault
outputs
Refer to Figure 4-5 for a block diagram of the address decoder/driver card.
Figure 4-4. Address Decoder/Driver