ZETRON 2000 Series Especificaciones descargar pdf (Pagina 242)

System Configuration Files

242 025-9035AA

OPARAM Programming/TNPP Networking Using Version

8TNPP8C3

The node addresses that the TNPP card will respond to for Inbound pages are set in the

oparam.cds file. Unlike versions earlier than the 8TNPP8xx series, more than one node

address may be selected as “our address”. Each destination node address that the TNPP

card will recognize as one of its receiving addresses must have an entry in the oparam list

for the card. A destination address may be specified as routing to Central as a page, and/or

route out to another node. A maximum of 32 node addresses may be specified.

The node address is specified as four pairs of hex digits, which is a 32-bit number. The two

most significant bytes (high bytes) of the address currently are reserved; they should

always be zeros. Besides the node address itself, you must specify the inertia count, ports

to route the packet to, and ports to accept the address from. Central counts as a port. Any

destination address that is to generate pages locally must be routed to Central.

The ports to route to are specified as a bit field made of two bytes. The ports that a given

destination ID will be accepted from are specified in a similar fashion. The Multiport

hardware supports up to eight ports, which TNPP considers ports one through eight. This

numbering corresponds to the numbering used on the LEDs on the Multiport card. In order

to set the route-to destinations for a port, you should do the following.

♦ Setting route-to destinations:

1. Determine all the ports this node ID will route to.

2. Using Table 35, add together the bit numbers of all routed-to ports for the node.

3. Convert the sum to a two-byte hexadecimal value.

When a network packet is received at a serial port, or sent to the card from Central, the

destination node ID is looked up and the possible route-to ports determined. The bit

number of the port that received the page is first cleared before the TNPP card attempts to

route the packet, so that port will not be sent an “echo” of the packet.

Before routing is done that node's list of “accept-from” ports is checked. If the port the

packet was received at is in the list, then the packet is accepted for routing. If it is not in

the list, the packet will not normally be routed, and the reply to the sending node will be

<CAN> or <ACK>, depending on the BAD_PORT setting in the receiving port’s options

field. BAD_PORT is part of the opcode “05” settings, the port programming opcode.

Besides the BAD_PORT, setting the port programming allows you to specify the handling

of packets not routed by the node table. It thus allows default routing on a per-port basis.

Please note that, the port receiving the packet need not have a bit set in the route-to field.

As an example a simplex in link, such as for Network USA, will never have a packet sent

to it and thus will never be routed to. For a terminal with just Network USA Satellite

paging only Central, port zero, will ever have a page routed to it.

The route to mapping may be changed by destination remapping. This is covered in depth

later.

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ZETRON 2000 Series Especificaciones Pagina 242