TV One C2-2375A Series, Руководство по эксплуатации

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C2-2375A S
ERIES
O
PERATION
M
ANUAL
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10 SERIAL / IP CONTROL SPECIFICATION
PLEASE NOTE: Not all units support Serial and/or IP (Ethernet) communications –
check to see if this feature is present on your unit.
This section outlines how to control a unit via a Serial or Ethernet link (if fitted to
your unit), using ASCII-based commands. It details how to send and receive serial
data to perform many of the functions that a user has access to on the unit.
Not all units will support the full range of adjustments listed – this will depend on the
complexity of the unit you have.
10.1 Communication protocol basics
Packets of ASCII data containing hexadecimal numbers are exchanged between
the unit and controller via a Serial or IP link (you cannot use both at the same time).
The Serial standard is 57600 baud, 8 bits, no parity and 1 stop bit, although this can
be changed by the user (see ‘System’ menu).
No flow control is used - however all control packets start with an ASCII 'F', end
with carriage-return (13 decimal, 0x0D hexadecimal) and all such packets sent to
the unit will be acknowledged (thereby provided software handshaking). Note that
a line-feed (LF) should not be sent.
It may take around 30ms (0.03 seconds) for an RS232 command to be actioned
and acknowledged – this will vary between different models.
ASCII-hex data is used where a number is encoded into its hexadecimal equivalent
with leading zeros – e.g. Where '00' is decimal value 0, '80' is decimal 128 and 'FF'
is decimal 255. In other words, two characters are sent for each byte encoded.
Any gap of more than 1 second between the characters of a control command sent
will cause a time-out - and previous characters sent will be lost.
Write packets (sending command functions to the unit) are always 20 characters
long (including a carriage return at the end). The unit will respond with a full 20
character message indicating what has changed. This returned payload will reflect
the actual value of the parameter changed. If the user requests a value out of
bounds then the limit value is used, and the payload will then reflect the limited
value used.
Read packets (sent to request information from the unit) are always 14 characters
long (including a carriage return at the end), the response from the unit will be a 20
byte message with the Write flag (since it is ‘writing’ the value back to the host) and
the ACK flag set.