Areva KITZ 101, User Manual

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The normal operational mode of the KITZ unit uses the 11 bit frame format.
However, some equipment to which the KITZ unit is to be interfaced can only
support the 10 bit frame format (eg. most modems).
The use of the 10 bit frame format will result in a less secure communications
protocol which does not meet the IEC-870 - 5 FT 1.2 requirements.
5.4 Time tagging of K-Bus messages
The fifth switch (switch 4) appends an IEC-870 format time tag (using the KITZ
RTC‘s current time) to a received K-Bus message.
The KITZ Interface unit will insert an IEC-870 format time tag into a converted
IEC-870 courier message if all of the following conditions apply:
1) Switch 4 (fifth from left is set).
2) The message contains a millisecond timer count (DTL Type 38h - 3Bh).
3) The message contains a courier status byte (or bytes) (DTL Type 5Ch - 5Fh).
4) An IEC-870 time tag (DTL Type 3Ch - 3Fh) is not already contained before
the status byte within the message.
The IEC-870 time tag will be added after the millisecond count.
The time tag format is shown below.
IEC TIME Extended
ms. Minutes Hour Day Month Year
DTL (EXT) Length
3C 07 0 - 59999 0 - 59 0 - 23 1 - 31 1 - 12 0 - 99
The IEC-870 time tag value is the time of reception of the first byte of the K-Bus
message.
If switch 4 is not set, the millisecond counter of the relay reply will be adjusted to
take account of protocol conversion delays.
5.5 Modem control
The Modem Set-up and Modem Present switches control the KITZ unit mode of
operation when connected to a modem. This is shown in the following table:
Modem Modem Function
Present Set-Up
(Switch 5) (Switch 6)
Position 0 Position 0 Normal operation - Modem control lines (CTS, DSR
and DCD) ignored. DTR always active, RTS reflects
Receive/Transmit state.
Position 1 Position 0 Modem control lines (CTS (Tx), DSR (Rx) and DCD
(Rx)) must be active to START (see note)
communication. DTR always active, RTS reflects
Receive/Transmit state.
Position 0 or 1 Position 1 Communication disabled on RS232
and K-Bus ports.
Table 5. KITZ RS232 modem control.