SC Channels


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8. SC Channels

The Serial Communication Channels menu enables the setup of all SCC parameters available, ranging from physical layer parameters to the network interface ones. It is divided into CNI, Protocol and Extensions submenus.

8.1. SC Channel to Node Interface

The CNI menu is identical for all channel types. For CNI menu description see chapter Chapter 25, CNI-channel to node interface.

8.2. SC Protocol

This submenu contains both low-level channel parameters (bit rate, handshaking, etc.) and access module configuration (type of protocol supported and its parameters).

From MORSE main menu type SPe Enter Enter:

    n     m     g    b   p8   i   s  XRC D G    o
(0)RS232 ASYNC  SW  19200N81  5 1600 — D 0 MARS-A
(1)RS232 ASYNC  SW  19200N81  5 1600 — D 0 MARS-A
(2)RS232 ASYNC  SW 115200N81  5 1600 — D 0 ASYNC LINK
    n     m     g    b   p8   i   s  XRC D G  o
(0)RS232 ASYNC  SW  19200N81  5 1600 --- D 0 MARS-A
(1)RS232 ASYNC  SW  19200N81  5 1600 --- D 0 MARS-A
(2)RS232 ASYNC  SW 115200N81  5 1600 --- D 0 ASYNC LINK
(3)RS232 ASYNC  SW  19200N81  5 1600 --- D 0 MARS-A

type 1 Enter

Serial Communication Channels:
i(n)t:RS232  (m)ode:ASYNC   dia(g):SW
(b)it/s:19200  (p)ar:NONE  (8)bit:ON  s(T)op:OFF  fr(A)gs:7+9/16
RX (i)dle:5 RX buf (s)ize:1600
TX idl(e):OFF
Handshake: (X)on/Xoff:OFF  (R)TS:OFF  (C)TS:OFF
C(D):ON  (G):0000
pr(o)tocol MARS-A parame(t)ers
ext clocks t(x):OFF  (r)x:OFF sync (w)ord:7E7E

— the interface type

  • (2)RS232 – the American version of the V.24 standard, for connector pin layout see, Support, Radio modems, MR25, Manual


    For other interface use external converter OPI 422 or OPI 485.

  • (2) RS232 – the American version of the V.24 standard, for connector pin layout see, Support, Radio modems, MR400, Manual

  • (4) RS422 – for RS485 module without clamps interconnection

  • (8) RS485 – for RS485 module with clamps connected according to RS485


— link layer low level mode (part of SCM), it is automatically derived from the selected protocol

  • (a) ASYNC

  • (b) BISYNC

  • (h) HDLC

  • (v) V.110


— diagnostic mode (part of SCM)


— normal (not used, RTS/CTS signals are controlled by the hardware)


— signals transmitted on the channel from the processor are sent back immediately


— signal arriving at the port from external equipment is received, and immediately echoed back


— standard configuration, the handshake is controlled by the software, including RTS/CTS

Signal way through interface

Fig. 8.1: Signal way through interface

  • LOOPBACK – Echoed inside CU firmware, thus before RS232 or RS422 converters.

  • ECHO – Echoed inside CU firmware. Signal goes through RS232 or RS422 converters to the processor and back.


— transmission speed in bits per second, to be written in hundreds (type b1152 to get 115200, or b6 to get 600)


— parity setting (part of SCM)

  • (n)NONE — without parity checking

  • (e)EVEN — even parity

  • (o)ODD — odd parity


— number of data bits (part of SCM)

  • ON — 8 bit

  • OFF — 7 bit


— the stop bit length consists of the optional part s(T)op and the constant part with the adjustable length fr(A)gs. The part s(T)op is present upon selecting ON and omitted at OFF.


— this part of the stop bit is present permanently. It’s length is adjustable by exchanging the number 7 by 0 to 7, the resulting length is from 9/16 to 16/16 period.

The total length of stop bit can be set using both parameters s(T)op and fr(A)gs in interval 0.563 to 1.000 or 1.563 to 2.000 bits.

The double port SCC2+3 in MR400 series can use the parameter s(T)op only. The fr(A)gs parameter has the value 16/16 permanently. The total length can be set to 1 or 2 bits.

RX (i)dle:5

— number of idle characters received from connected equipment before the RX buffer is closed. The lowest possible setting is recommended (5 characters in most cases).

RX buf (s)ize:1600

— the maximum size of the receiving buffer on the relevant SCC port – the possible maximum value is 1600 bytes

TX idl(e):OFF
  • OFF – no idle transmitted

  • ON – one idle character is transmitted ahead of every frame

(X)on/Xoff: OFF/ON

— ON = handshake performed by transmitting control characters XON and XOFF from both DCE(CU) and DTE


— ON = DCE transmissions are controlled from DTE by RTS


— ON = DCE controls DTE transmissions by CTS


— sets the initial level of the CD signal


— protocol (access module) debug messages level (0 means no debug messages)


— selects the protocol supported by the access module, the list can be changed in new firmware versions:

Select new protocol:

(n)-NONE                 (B)-ALLEN-BRADLEY DF1 
(c)-COMLI                (g)-L&G 870-5-2 IEC 
(h)-HIRSH                (H)-HIRSH-D 
(y)-HAYES                (G)-GPS 
(t)-TRAN SYNC            (X)-EXT SYNC 
(M)-MITSUBISHI           (s)-SERVICE 
(A)-ASYNC HDLC           (l)-LAP12 
(b)-ASYNC LINK ++        (e)-MARS-E 
(m)-MARS-M               (R)-MARS-U 
(N)-MARS-N               (i)-MININET 
(T)-MTS                  (o)-REM 
(r)-RDS                  (u)-SAUTER 
(p)-PR2000               (I)-UNI 
(U)-SURN                 (S)-S-BUS 

(s)-SCHENCK              (j)-JOHNSON CONTROLS 
(z)-ZAT                  (E)-ECS 
(R)-RTU                  (M)-MODBUS 
(I)-DIRAS                (P)-PPP 
(L)-SLIP                 (D)-DCF 
(p)-PROFIBUS             (F)-FBII 
(S)-SKAO                 (o)-SKAO-MODBUS 
(d)-DEBUG                (r)-RADOS 
(e)-RP570                (t)-PROMOTIC 
(c)-MELSEC C24           (a)-PARK AIR 

(a)-MARS-A               (r)-RLA 
(s)-SMS                  (m)-MDU 
(i)-INCA                 (t)-ARITECH 
(S)-SEP                  (A)-Axima 
(f)-Sifas                (b)-SEAB 
(g)-AEG                  (d)-DACP 
(w)-WSR                  (F)-AGFA 
(p)-APE                  (n)-ABSONET 

— access module parameters (a different set for each respective protocol), see, Support, Interface Protocols

ext clocks: OFF

— switching internal/external clock at RXC pin (for synchronous modes only)

(r)x: OFF

— switching internal/external clock at TXC pin

sync (W)ord: 7E7E

— sync word (for some of synchronous modes)

SC(M): 0171

— the SCM register content, for SCC special settings, not used during normal configurations

8.3. SC eXtensions

From MORSE main menu type SXe Enter Enter:

Extended parameters for SCC, supplementary parameters for some protocols. Using the menu SXe for control gprs module see the article PPP-GPRS protocol for MG100.

After entering the SXe menu the state of registers must be read using the r Enter command. When the editing changes are made, save them using the w Enter command. The initialisation do in SPe menu using the (I)nit command or by total reboot.

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