The Radio frequency channel menu enables the setup of interface and protocol parameters independently for each RFC and common properties for the RF modem as a whole.
The CNI menu is identical for all channel types. For CNI menu description see chapter Chapter 25, CNI-channel to node interface
Medium access layer and link layer parameters together with mobile mode parameters are set here. It replaces the old menu RF Protocol (FPe) since version 9.0.0.0.
From MORSE main menu type FAe Enter Enter :
Rfc access params: Access (M)ode:HCSMA t(Y)pe:NORMAL (h)is TO:30 (H)i/Lo rate:2 Qf(U)ll thr:10 hip(R)q cnt:5 High priority: (d)el:16000us (l):16000us (n)um:4 (T)O:10s ACK TO=f(i)x:600ms+[0..3]*(v)ar:400ms r(e)p:5 (P)rog:OFF coding (m)ode:REP (t)ype:DBL Low priority: (D)el:16000us (L):16000us n(u)m:4 T(O):10s ACK TO=fi(x):600ms+[0..3]*v(a)r:400ms re(p):5 Pro(g):OFF coding m(o)de:REP t(y)pe:DBL de(f)ault (r)ead (w)rite (I)nit (S)ync (q)uit
The packet coming from the node to RF channel is not transmitted immediately. The radio channel access procedure detects, when the RF channel is free and only now is the packet sent. Meantime the packet waits in one of ten queues. One queue for each toa address is occupied. Part of the queues is used for the high priority channel, part for low priority. The packets are classified in the queues according it’s handicap bit. It is assigned to each individual packet when coming from user channel to the node, see the menu CNI. The transfer of this bit at the retransmission is in the development. At present (version 10.0.28.0) it is not transferred. The packet are also in the next radio steps putted in the queues with the high priority.
This principle is applied for CU MR25 from fw 9.0.32.0 with limited extent of queues (number of queues 5, depth max. 5).
RFC access params
Common parameters for both priority levels:
| (M):HCSMA | Access (M)ode:HCSMA – switch-on the HSCMA mode
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| (Y):NORMAL | t(Y)pe:NORMAL – Type of access to the RF channel
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| (h):30 | (h)is TO:30 – time dimensions (sec)of list of received packets, which is used for discarding of repeated packets |
| (H):2 | (H)i/Lo rate:2 – the rate of packet transmitting frequency from the high priority queue and from the low priority queue. The high priority packets are transmitted here twice more often. |
| (U):10 | Qf(U)ll thr:10 – the special packetlost is generated after reaching this number of packet in the queue. The packet continues to be accepted until the maximal queue length 10 packets. |
| (R):5 | hip(R)q cnt:5 – the number of high priority queues. Next 10-R-1=4 queues have the low priority, one queue is the collecting. It collects packets having the toa address, to which is not available a free queue. This queue collects the packets without regard to the packet priority level. |
High priority
The parameters for packet having the high priority. The analogical parameters follows for the low priority queues.
Access
The time in which the radio tests the RF channel consists of a fixed part (fixed access period) and a random part (slot length multiplied by a random number), access period=d+r×l, where r comes from the interval 0 to (n-1). The fixed part (typically 16 ms) allows the ACK to pass without interference.
(d):16000 | (d)el:16000us – Fixed part of access period in microseconds |
(l):16000 | (l):16000us – Slot length in microseconds |
(n):4 | (n)um:4 – Max. number of slots When the channel access tunning it is recommended to let the (d)el and (l) parameters on the values 16000 (for 25kHz channel) and change the (n)um only. |
(T):10 | (T)O:10s – Access timeout in sec. The time limit for the station to try and get onto the RF channel. If this timeout is exceeded, the modem discards the packet and sends an error message. |
ACK
ACK timeout is the period that the RFC protocol waits for acknowledgement from the counterpart. To avoid collision deadlock between stations transmitting long packets and not detecting other’s signal (i.e. CSMA principle cannot work), it is recommended to set time values which correspond to the maximum transmission time of the supposed longest packet to both parts of the ACK timeout.
| (i):600 | ACK TO=f(i)x:600ms – fixed part of ACK timeout in ms |
| (v):400ms | +[0..3]*(v)ar:400ms – variable part of ACK timeout in ms |
| (e):5 | r(e)p:5 – The maximum number of repeated messages on the RF channel (unacknowledged by the counterpart) |
| (P):OFF | (P)rog:OFF – for service purposes |
Coding
The data coding in the RF channel
| (m) | (m)ode:REP – the coding activation
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| (t) | (t)ype:DBL – type of coding of RFC data
|
This menu is replaced by a new one FAe (RF Access) since 9.0.0.0 version. The mobile mode parameters are relocated into menu DGei.
Medium access layer and link layer parameters together with mobile mode parameters are set here.
From MORSE main menu type FPe Enter Enter :
RF channels:
Access |ACK |coding |Mobile
id a del l num TO|fix var rep P hT|mod typ|base mask center per
(0) NORMAL 16 16 4 10| 600 400 5 30|REP DBL|OFF
(1) NORMAL 16 16 4 10| 600 400 5 30|REP DBL|OFF
(2) NORMAL 16 16 4 10| 600 400 5 30|REP DBL|OFF
(3) NORMAL 16 16 4 10| 600 400 5 30|REP DBL|OFF
(4) NORMAL 16 16 4 10| 600 400 5 30|REP DBL|OFF
de(f)ault (r)ead (w)rite
(I)nit (S)ync
(q)uittype 1 Enter
Radio Frequency Channels: (a)ccess type:NORMAL (d)el:16ms (l):16ms (n)um:4 (T)O:10s ACK TO=(f)ix:600ms+[0..3]*(v)ar:400ms (r)ep:5 (P)rog:OFF (H)ipr:OFF (h)is TO:30 coding (m)ode:REP (t)ype:DBL (M)obile mode:OFF (b)ase:00000000 mas(k):00000000 (c)enter addr:00000000 (p)eriod:0sec
Access
The time in which the radio tests the RF channel consists of a fixed part (fixed access period) and a random part (slot length multiplied by a random number), access period=d+r×l, where r comes from the interval 0 to (n-1). The fixed part (typically 16 ms) allows the ACK to pass without interference.
(a)cces type | — Type of access to the RF channel
|
(d)el:16ms | — Fixed part of access period in ms. |
(l):16ms | — Slot length in ms. |
(n)um:4 | — Max. number of slots. When the channel access tunning it is recommended to let the (d)el and (l) parameters on the values 16 (for 25kHz channel) and change the (n)um only. Lower (n)um causes the higher priority and conversely. |
(T)O:10s | — Access timeout in sec. The time limit for the station to try and get onto the RF channel. If this timeout is exceeded, the modem discards the packet and sends an error message. |
ACK
ACK timeout is the period that the RFC protocol waits for acknowledgement from the counterpart. To avoid collision deadlock between stations transmitting long packets and not detecting other’s signal (i.e. CSMA principle cannot work), it is recommended to set time values which correspond to the maximum transmission time of the supposed longest packet to both parts of the ACK timeout.
ACK TO=(f)ix :600ms | — fixed part of ACK timeout in ms |
+[0..3]*(v)ar: 400ms | — variable part of ACK timeout in ms |
(r)ep: 5 | — The maximum number of repeated messages on the RF channel (unacknowledged by the counterpart) |
(P)rog: OFF | — for service purposes |
| (H)ipr:OFF | — for service purposes |
(h)is TO: 30 | — time dimensions (sec)of list of received packets, which is used for discarding of repeated packets |
Coding
The data coding in the RF channel
coding (m)ode: |
|
(t)ype: | — type of coding of RFC data
|
Mobile mode
The mobile station parameters
(M)obile: OFF/ON | — setting this parameter switches the RFC to mobile mode |
(b)ase: 00000000 | — comparative address for choice of base stations |
mas(k): 00000000 | — if any station which can be received on the RF 0 channel is to be taken as base, masked parts of the (b)ase parameter and the base station address must be equal |
(c)enter: 00000000 | — address of central station, where this mobile has to report to |
(p)eriod: 0sec | — period (sec) for reporting to the central station (0 means no periodical reports are sent) |
The RF modem configuration data (common for all RFCs, as there is only one physical RF channel). It is strongly recommended to use default values here.
From MORSE main menu type FMe Enter Enter
RF Modem: RFTX disabl(e):OFF (m)ode:MORSE invert (T)X:ON (R)X:ON TX blocks: (i)dle:0 sy(n)c:3 DQ (t)reshold:5 Valid for SW < 805 (s)ync TO:40 RSS treshol(d):105 RSS m(o)de:RSS treshold FX(9)19 FX(5)89 (W)dog:0min (l)oging:OFF de(f)ault (r)ead (w)rite (I)nit (S)ync (q)uit >>
RFTX disabl(e): OFF |
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(m)ode: MORSE |
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invert (T)X: OFF/ON | — TX and/or RX modulation inverted; use default values when in doubt |
invert (R)X: OFF/ON | — TX and/or RX modulation inverted; use default values when in doubt |
TX blocks: (i)dle:0 | — the delay before sync.blocks transmitting |
(s)ync: 3 | — number of sync blocks transmitted (6 bytes each) |
(s)ync TO: 40 | — frame sync timeout (msec); after detecting the first sync
byte the RF modem is waiting for frame synchronisation sequence .
When this timeout expires, the Noise sync counter is incremented
(see |
DQ (t)reshold:5 | — DQ limit for access to the channel – RFC does not start
the transmitting when the audible signal better then set limit
occurs on the RFC, it is replaced by MR25 from fw 10.0.50.0 employs DQ treshold only MR400 from fw 10.0.50.0 employs RSS treshold only |
RSS treshol(d):105 | — access to the channel – RFC does not start the transmitting when the audible signal stronger then set limit occurs on the RFC, the RSS treshold is used for the MR400 series since fw 806 |
RSS m(o)de: | — for MR400 series only
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FX(9)19 | — setting of the signal processor for MR25 and MR400, the
|
FX(5)89 | — setting of the signal processor for MR900, the parameter
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(W)dog: | — for service purposes |
(l)oging: | — for service purposes |