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TTM 01-G Manual / October 2018
22
String-A Time Code O/P
Table 9 details the String A serial string format and fields.
About
This code is very similar in data content to the IRIG J-17 code but adds a two-character field
containing the year, and uses 8-bit ASCII, no parity data format.
Timing
Transmitted once every second. The leading edge of the “start” bit of the first character
<SOH> is exactly on the second that the message describes.
Default Comms
9600 bps, 8-bit ASCII, no parity
Definition
<SOH>ddd:hh:mm:ss:yy<CR><LF>
Placeholder
Content
<SOH>
Start Of Header: HEX 01
ddd
Day of Year: range “001” – “366”
:
HEX 3A
hh
hour: “00” – ”23”
:
HEX 3A
mm
minute: “00” – “59”
:
HEX 3A
ss
seconds: “00” – “59”
:
HEX 3A
yy
year: “00” – “99” representing the last two digits of the year since 2000
<CR>
Carriage Return: HEX 0D
<LF>
Line Feed: HEX 0A
Table 9 - String A Time Code Format Fields
Example:
Interpretation:
<SOH>112:12:34:36:10<CR><LF>
day 112, time 12:34:36, year (20)10