![background image](http://html1.mh-extra.com/html/zetron/640-dapt-xtra/640-dapt-xtra_installation-and-repair-manual_3549374040.webp)
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.
Summary of Contents for 640 DAPT XTRA
Page 2: ......
Page 6: ...Statements vi 025 9416...
Page 20: ...Introduction 8 025 9416...
Page 26: ...Specifications 14 025 9416...
Page 96: ...Installation 84 025 9416...
Page 126: ...Optional Equipment Installation 114 025 9416...
Page 134: ...Voice Prompts 122 025 9416...
Page 174: ...Parts Lists and Schematics 162 025 9416 Schematic...
Page 175: ...Parts Lists and Schematics 025 9416 163...
Page 176: ...Parts Lists and Schematics 164 025 9416...
Page 177: ...Parts Lists and Schematics 025 9416 165...
Page 178: ...Parts Lists and Schematics 166 025 9416...
Page 179: ...Parts Lists and Schematics 025 9416 167...
Page 180: ...Parts Lists and Schematics 168 025 9416...
Page 181: ...Parts Lists and Schematics 025 9416 169...
Page 182: ...Parts Lists and Schematics 170 025 9416 Silkscreen...
Page 185: ...Parts Lists and Schematics 025 9416 173 Schematic...
Page 186: ...Parts Lists and Schematics 174 025 9416...
Page 187: ...Parts Lists and Schematics 025 9416 175...
Page 188: ...Parts Lists and Schematics 176 025 9416...
Page 189: ...Parts Lists and Schematics 025 9416 177...
Page 190: ...Parts Lists and Schematics 178 025 9416 Silkscreen...
Page 193: ...Parts Lists and Schematics 025 9416 181 Schematic...
Page 194: ...Parts Lists and Schematics 182 025 9416...
Page 195: ...Parts Lists and Schematics 025 9416 183...
Page 196: ...Parts Lists and Schematics 184 025 9416 Silkscreen...
Page 198: ...Parts Lists and Schematics 186 025 9416 RAM Disk 702 9386B ROM Disk 702 9389B...
Page 199: ...Parts Lists and Schematics 025 9416 187 TNPP Interface 702 9362C 2...
Page 200: ...Parts Lists and Schematics 188 025 9416 Terminal Block Adapter 702 9470B...
Page 201: ...Parts Lists and Schematics 025 9416 189 CONFIGURATION DIAGRAMS Dual Trunk Telco DID 024 0076A...
Page 202: ...Parts Lists and Schematics 190 025 9416 Dual Trunk Telco End to End 024 0077A...
Page 203: ...Parts Lists and Schematics 025 9416 191 Dual Trunk Telco E M 024 0078A...
Page 204: ...Parts Lists and Schematics 192 025 9416 Dual Trunk Telco Ground Start 024 0079A...
Page 210: ...025 9416...