Echotrac CV100
User Manual
Page 32 of 32
Odom Hydrographic Systems, Inc.
May 28, 2008
6.4 Serial Data input / Chart annotation
Information that in the past was handwritten on the chart record can be transmitted to the Echotrac via the RS232
return line (ASCII Serial Input). Up to 80 ASCII characters per line can be accommodated.
Event Line (
Fix Mark)
A single line across the chart is produced by sending HEX 06 (ASCII "ACK" or "Control F"). An event line will be
printed across the chart at the end of the current sounding cycle and will not delay or interfere with normal
operation of the unit.
Event Annotation
When required, the event line can be annotated with up to 80 characters of information. This is achieved by
following the HEX 06 with HEX 01 (ASCII "SOH" or "Control A"). Once the HEX 02 is transmitted, annotation
characters can be sent sequentially or with breaks between characters. The ASCII string should be delimited by
a HEX 04 (ASCII "EOT" or "Control D"). This will cause the annotation to be printed and will return the
ECHOTRAC to normal operation.
**
Note: Event annotation must contain at least one character before the HEX 04 delimiter even if it is only a
HEX 20 ("space"). Care should also be taken to avoid annotation overrun, which is caused by grouping
annotated events so closely together that they obscure the record.
Header Information (
multiple line annotation
):
This type of information would normally be hand-written at the start or end of a survey line and would include
information relating to date, time, work area, etc. Using the Heading Information input facility it is possible to have
this information printed automatically on a blank section of chart. Each line is still limited to the maximum of 80
characters but there is no limit to the number of lines of annotation.
Header information is sent in the same way as Event Annotation (see above) except that a HEX 0D (ASCII "CR")
delimits each line of information. The HEX 04 ("Control D") is transmitted only at the end of the complete header
text. The following procedure steps through each phase of the Header Information input:
1
Transmit HEX 01 to request an annotation input.
2
Transmit a line of header information to a maximum of 80 characters.
3
Transmit HEX 0D ("CR") to print the line.
4
Transmit next line of Header Information.
5
Repeat step 3 and 4 as required until all Header Information is sent.
6
After the last "CR", send the HEX 04 delimiter to return ECHOTRAC to normal operation.
(In order to advance blank paper, send the HEX 0D ("CR") as many times as necessary.)
