Serial Ports

Connector Pin-out & Data I/O Set-up

The Data I/O port is accessed using an industry standard DB-25 plug which is provided as part of the basic Bathy-500MF delivery. Pin designations are shown below.

1.         Chassis Ground
2.         RS-232 TXD   ~ DATA LOG OUT
3.         RS-232 RXD   ~ GPS IN
4.         RS-232 RTS
5.         RS-232 CTS
6.         RS-232 DSR
7.         Signal Ground
8.        (unused)
9.        RS-422 TXD +     ~ DATA LOG OUT
10.        RS-422 TXD -      ~ DATA LOG OUT
11.        RS-422 RXD+      ~ GPS IN
12.        RS-422 RXD         ~ GPS IN
13.        RS-422 RTS+
14.        RS-422 RTS
15.        RS-422 CTS+
16.        RS-422 CTS
17.        RS-422 DSR+
18.        RS-422 DSR-
19.        (unused)
20.        RS-232 DTR
21.        (unused)
22.        (unused)
23.        RS-422 DTR+
24.        RS-422 DTR-
25.        (unused)

Note: Bathy-500MF units are shipped from the factory preset for RS-232. Jumper must be changed to enable RS-422 (NOTE:Only one jumper block is to be installed at any time).

Data Input /Output Wiring Diagrams

RS-232 Wiring Diagram

RS-422 Wiring Diagram

Data Formats - Input

In lieu of GPS position your Bathy-500MF will accept external annotation from various PC-based hydrographic software; Up to forty-four characters (Alphanumeric-uppercase) may be printed vertically. Serial input is made to the same hardware pins as is used for GPS input.

To start an annotation string, "CONTROL F" then "CONTROL A" is inputted; This is followed by up to forty-four characters, then "CONTROL D" to end the string. Simply put, the sequence is shown below.

(CNTRL F) (CNTRL A) (ANNOTATION) (CNTRL D)

Should the user not desire vertical annotation but instead desire a vertical fix mark line, only a (CNTRL F) need be sent from the PC.

Data Formats - Output

This output emulates the ODOM Echotrac output sentence as shown in the example below.

_E T_ _ _ x x x x <CR>

During normal operation the "space" in front of the "E" will be blank; When a Fix Mark is initiated, this space will contain the character "F". During proper equipment operation, the "space" immediately after the "T" is blank; Should the bottom be lost, an error condition s indicated by the character "E" being placed in this space.

Output in "FEET" units is denoted as "ET" while output in "METERS" is denoted as "et".

The example, "x x x x" indicates three digits in front of the decimal point and thus one digit after when in English mode (i.e. "1234" equals 123.4 feet). If in Metric mode, there would be two places after the decimal, thus "1234" equals 12.34 meters. Note that zeroes are suppressed.

The structure for this industry standard output is shown below.

_D T_ _ _ x x x . x _FT <CRLF> (English mode)

_D T_ _ _ x x . x x _MT <CRLF> (Metric mode)

 During normal operation the "space" in front of the "D" will be blank; An "E" in this space indicates an error such as lost bottom while an "F" indicates a Fix Mark.

Data output will be NMEA 0183 depth below transducer sentence format as shown below.

$ S D D B T , x x x . x , f , x x x . x x, M , x x . x , F <CRLF>

Where x x x . x = feet (f) x x x . x x = meters (M) x x . x = fathoms (F)

Data Output will be NMEA 0183 depth belowsurface sentence format as shown below.

$ S D D B S , x x x . x , f , x x x . x x , M , x x . x , F <CRLF>

Where x x x . x = feet (f) x x x . x x = meters (M) x x . x = fathoms (F)

This data output emulates the output sentence of the Atlas DESO-25.

D A x x x x x . x x Ft * (English mode)

D A x x x x x . x x _m * (Metric mode)

Note that an asterisk is always used as a terminator at the end of the sentence. Also note that in the Metric mode, a blank space will always appear in front of the "m" character.

Your Bathy-500MF emulates the digital depth output of the ODOM Digitrace depth digitizer unit.   The ODOM standard output data string contains 11 characters as shown below; No parity is used and the sentence has 8 data bits and 1 stop bit.

Byte 1:

An ASCII "F" (hex 46) appears as the first byte in the string whenever the operator depresses the recorder MARK key. The depth value in the output string reflects the depth at the point which the key is pressed. At all other times the ASCII "space" (hex 20) appears at this location.

 

Byte 2 & 3:

Characters 2 and 3 contain the unit identifiers. These are set to "D" and "T" (hex 44, 54).

 

Byte 4:

Position 4 is reserved as an error indicator in the form of an ASCII "E" (hex 45) and coincides with all zeros in the depth field. An ASCII "space" is present at all other times.

 

Byte 5:

This location will always contain the ASCII "space".

 

Byte 6 thru 10

True depth is given in these five positions with the decimal point understood to be fixed between bytes 8 and 9. Leading zero suppression is applied to the first two digits of depth. For example, for a depth of 8.5 feet, the five digits would appear as: space/space/8/5/0.

Depth in the output sentence will be corrected for Offset and Speed of Sound. In the event of an error due to loss of bottom tracking two zeros will appear in the depth field and the "E" character will occur in byte 4.

Byte 11:

A carriage return <CR> delimiter (hex )D) is always placed at the end at the string.