Instruction manual

Hardware Overview
28 025-9416
RAM DISK BOARD
The RAM (random access memory) disk (Part No. 702-9386) stores the voice prompts and data-
base information. It could also contain paging software in some circumstances to avoid updates
to the ROM disk board. The RAM disk (item #7, Figure 2) is essentially like a hard drive in a
computer.
The RAM disk board is very similar to the ROM disk in design. It usually includes four 128KB
RAM chips along with the associated battery back-up circuitry. Some applications will require
more storage. There can be a total of eight 128KB RAM chips installed for a total of 1MB of
non-volatile storage.
While the RAM disk is protected by plastic on the solder-side, care should be taken when work-
ing around the RAM disk board. If it becomes corrupt (due to static discharge, lightning, etc.),
the contents will be lost and a reformat process must take place. Refer to Section 9 for inform-
ation on reformatting the RAM disk. After the reformat, the database and prompts must be
reloaded by the restore process. Contact the factory if you suspect the RAM disk is damaged.
Jumper Settings
The jumper locations and settings on the RAM disk are identical to those on the ROM disk. They
should be set appropriately for the installed configuration as shown in Figure 8 and described in
the preceding paragraph.
TNPP INTERFACE
The TNPP (Telocator Network Paging Protocol) interface board (Part No. 702-9362) enables the
Model 640 to receive and pass pages to increase the paging region. The TNPP interface plugs
into the main processor motherboard at J8. The board (item #8, Figure 2) comes with two bidi-
rectional 9-pin serial ports for easy connection to the network link. The TNPP Options (Part No.
950-9294 dual interface and Part No. 950-9470 unidirectional interface for satellite downlink or
ZAPP! alphanumeric entry stations) setup the paging terminal for wide-area network paging. See
Section 9 for details on the six LEDs on the TNPP interface.
The Dual Serial Card Option (Part No. 950-9469) enables the Model 640 to receive alpha-
numeric input. The DB-9 connectors are used just like the trunk card RS-232 serial ports.
TAP Inbound
The Model 640 can support inbound TAP (Telocator Alphanumeric Protocol) calls by way of the
modem capability built into the dual trunk interface boards. Any one of the four possible tele-
phone trunk inputs may be configured to handle the inbound TAP calls.
TAP Outdial
The TNPP board is also used for TAP outdial applications. When an external modem is inter-
faced with this card, the Model 640 can send display pages to other TAP-compatible paging
terminals on a dial-up connection.