Specifications
247
OPARAM Programming/TNPP Networking Using Version 8TNPP8C3
Table 36: TNPP Port Timing Parameters
Physical Node ID
The last oparam for the TNPP card uses the same opcode and general format as the older
TNPP versions opcode “17”. This line serves two purposes. The first is to signal that all
the TNPP oparams are done. The second is to set the physical node ID of the terminal.
This is used as the source ID in all pages originating on this terminal. Only the “us”
portion must be set, for this version of TNPP software our address must always be non-
zero.
The “reject” and “block” fields are most useful for situations where a terminal is both
receiving Network USA pages from a satellite downlink, and sending pages to the
Network USA uplink. In this case, the page sent to Network USA from one port will later
appear at the satellite downlink port. This situation can cause problems such as “echoing
pages” unless special action is taken. This topic is covered in depth, along with node ID
remapping, elsewhere.
Bytes Default Description
hh 14 (2.0) T_ICT Intercharacter timeout, 0.0 .. 25.5 seconds in 0.1
second increments.
hh hh 00 3C (60) T_IDLE Idle link timeout value, 0 .. 65,535 seconds.
hh 0A (10) T_NRE response to ENQ timeout value, 0..255 seconds in 1
second increments.
hh 06 (6) C_ENQ maximum ENQ retries before error logging, 0 .. 255
count.
hh 0A (10) T_NRI timeout when receiver idle, 0 .. 255 seconds.
hh 3C (60) T_NRB timeout when receiver busy, 0 .. 255 seconds.
hh 06 (6) C_RETRY maximum retries on sending a packet, 0 .. 255
count.
hh 0A (10) T_HOLD RS flag hold off time value, 0 .. 255 seconds.
hh 18 (24) C_HOLD max Re-transmissions in response to RS holdbacks,
0 .. 255 count.
cc count 0A
17 opcode for Physical Node programming.
nn nn Physical Node ID, two bytes, MSB first. The physical node
ID is only 16 bits.
pp pp Reject port bit mask, 16 bits as high byte, low byte. See
table above for bit mapping. A packet with this node's
physical ID as its source will be rejected by all ports set “on”
here, a <CAN> will be sent in response.