Wildlife Acoustics sm3bat User manual

SM3/SM4 FS RS-232 Monitor Interface User Guide
Wildlife Acoustics, Inc. page 1
SM3BAT/SM4BAT FS RS-232 Monitoring
Interface
The SM3BAT and SM4BAT FS implement a serial communications interface in
support of wind energy SCADA systems to report possible bat activity. With
firmware version 1.3.3 and later of the SM3BAT, or SM4BAT FS recorders produced
with serial numbers greater than S4U06942 (shipped on or after March 12, 2019),
the recorder responds to serial requests with information including cumulative
number of bat passes and pulses detected as well as timestamp, voltage,
temperature, and flash card capacity information.
NOTE: Firmware algorithms attempt to detect and count individual echolocation pulses
from bats and sequences of bat pulses based on configured parameters. Operators
should understand that some extraneous noise sources can cause false indications of bat
activity and that not all bat activity will be detected. The outputs should be used as part
of a site-specific statistical model capable of correlating these outputs to actionable events.
The protocol is “plug-and-play” in the sense that the SM3BAT or SM4BAT FS
automatically detects receiving the first request at either 38,400 or 19,200 baud
while recording bats. Once detected, the SM3BAT or SM4BAT FS will configure the
serial port and respond to subsequent requests with information.
The SM3BAT or SM4BAT FS is configured as per normal operation for recording
bats in triggered WAV mode. The various parameters and settings can be tuned for
defining the monitoring times and definitions of a valid bat pulse or pass.
Under normal operation (e.g. without the RS-232 interface), the SM3BAT or
SM4BAT FS would stop recording if the flash cards became full or unusable.
However, when the RS-232 interface is in use (e.g. if one or more requests have
been detected), the SM3BAT or SM4BAT FS will continue recording until cards are
full or fail, but will then continue monitoring/counting. In this mode, the LCD
display will indicate that the SM3BAT or SM4BAT FS is recording to the “Z” card
(instead of “A” through “D”) and the SM3BAT or SM4BAT FS will continue to
respond to requests over RS-232 with bat activity information.

SM3/SM4 FS RS-232 Monitor Interface User Guide
Wildlife Acoustics, Inc. page 2
Hardware Interface
The SM3BAT recorder hardware has an integrated RS-232 UART terminating with
an 8-pin Conxall weatherproof panel mount connector (equivalent to Switchcraft
7282-8PG-300) accessible from the exterior of the SM3BAT chassis. Wildlife
Acoustics can provide a shielded 3 meter mating data cable terminating in 8 wires
as follows:
SM3BAT
Pin #
SM3BAT
Data Cable
Wire Color
SM3BAT
Signal
name
RS-232 Signal
(DB9 pin)
Description (relative to
SM3BAT)
1
Green
Vcc
Output 3.3V (not used)
2
Black
TX
RD (2)
Output RS-232 data TX
3
Red
RTS
CTS (8) not used
Output RS-232 RTS (not used)
4
Orange
Enable
Output GPS enable (not used)
5
White
PPS
Input GPS time synch (not used)
6
Brown
RX
TD (3)
Input RS-232 data RX
7
Yellow
CTS
RTS (7) not used
Input RS-232 CTS (not used)
8
Blue
GND
GND (5)
Ground

SM3/SM4 FS RS-232 Monitor Interface User Guide
Wildlife Acoustics, Inc. page 3
SM4BAT FS recorders produced with serial numbers greater than S4U06942
(shipped on or after March 12, 2019), have an integrated RS-232 UART with signal
lines using 2 of the 5-pins used in for the external power connector, a 5-pin Conxall
weatherproof panel mount connector (equivalent to Switchcraft 7282-5PG-300)
accessible from the exterior of the SM4BAT FS chassis. Wildlife Acoustics can
provide a “V” cable terminating with one branch of the “Y” used for external power
to the SM4BAT FS and the other branch of the “Y” terminating in 4 bare wires as
follows:
SM4BAT-FS
Pin #
“Y” Cable
Wire Color
SM4BAT-FS
Signal name
RS-232 Signal
(DB9 pin)
Description (relative to
SM4BAT-FS)
1
Black
TX
RD (2)
Transmit data to network
2
Red
RX
TD (3)
Receive data from network
3
Blue
GROUND
GROUND (5)
Signal ground
4
POWER
External power for SM4BAT-FS
5
Green
Not used

SM3/SM4 FS RS-232 Monitor Interface User Guide
Wildlife Acoustics, Inc. page 4
Communications Protocol
The RS-232 interface is configured as 8-bit, no parity, and one stop bit (8N1) with
no hardware flow control. The least significant bit is transmitted first. Baud rates of
19,200 or 38,400 bits per second can be supported.
Customer equipment would send a 2-byte request to the SM3BAT as follows:
B<CR>
This is the same as (0x42 0x0d).
Within 50ms (typical), the SM3BAT or SM4BAT FS will respond with a response
formatted as follows:
BYYYYMMDDhhmmss,aa.a,bbb,ccc,ddddd,eeeee,fffff,ggggg,hh<CR>

SM3/SM4 FS RS-232 Monitor Interface User Guide
Wildlife Acoustics, Inc. page 5
Where the following fields are defined:
Field
Description
Number of bytes
B
Start character (0x42)
1
YYYYMMDDhhmmss
Timestamp
14
,
Delimiter (0x2c)
1
aa.a
Supply voltage e.g. 12.0
3-4
,
Delimiter (0x2c)
1
bbb
Internal temperature in Celsius (e.g. -20)
1-3
,
Delimiter (0x2c)
1
ccc
Flash cards full indicator, percentage of full
1-3
,
Delimiter (0x2c)
1
ddddd
Number of bat passes detected modulo 100,000
channel 0 since last power cycle
1-5
,
Delimiter (0x2c)
1
eeeee
Number of bat pulses detected modulo 100,000
channel 0 since last power cycle
1-5
,
Delimiter (0x2c)
1
fffff
Number of bat passes detected modulo 100,000
channel 1 since last power cycle
1-5
,
Delimiter (0x2c)
1
ggggg
Number of bat pulses detected modulo 100,000
channel 1 since last power cycle
1-5
,
Delimiter (0x2c)
1
hh
CRC-7 Checksum (two hexadecimal digits [0-9A-F])
2
<CR>
End of message (0x0d)
1
The maximum message length is 56 bytes including the “B” start character and
<CR> ending character. The CRC-7 checksum is calculated on the bytes including

SM3/SM4 FS RS-232 Monitor Interface User Guide
Wildlife Acoustics, Inc. page 6
the “B” start character through the “,” delimiter just before the checksum value
using the polynomial (x^7+x^3+1).
For example, the message “B20170522034559,6.1,26,5,8,153,0,0,3F”+<CR> would
be as of May 22, 2017 at 03:45:59 in the morning (24-hour time), battery
measuring 6.1V, internal temperature 26C, flash cards 5% full, 8 bat passes and 153
bat pulses, detected since the last power cycle, on channel 0 (and nothing on
channel 1) and a valid CRC-7 value of 0x3F.
Note that after power-up, the SM3BAT or SM4BAT FS may listen on the RS-232
port at 38,400 baud. If the customer equipment sends the request message at
19,200 baud, the SM3BAT or SM4BAT FS will detect a first character with the value
0x18 typically followed by two additional characters with undetermined values.
This is how the SM3BAT or SM4BAT FS could automatically detect if the customer
equipment is operating at 19,200 baud. If this is the case, the SM3BAT or SM4BAT
FS can reconfigure the UART to operate at this lower baud rate. As a consequence,
the first request message (or the first few request messages) after power up may
go unanswered.
Operational Considerations
Scheduling
The SM3BAT or SM4BAT FS can be programmed to monitor during specific periods
of the day, and “sleep” during other parts of the day to conserve power. When the
SM3BAT or SM4BAT FS is sleeping, it will not respond to RS-232 messages.
Therefore, the SM3BAT or SM4BAT FS must be programmed when to be
monitoring for bats: e.g. 24 hours or just at night, etc.
Recording
The SM3BAT or SM4BAT FS normally records the ultrasonic echolocation audio
data on up to 4 SDHC or SDXC flash cards. Full spectrum recordings can typically
consume 1-2GB of card space per night depending on bat activity. The flash cards
will eventually fill up. Normally, the SM3BAT or SM4BAT FS would shut down if it is
no longer able to make recordings. However, for this application, it is desirable to
continue monitoring, updating bat counters, and responding to requests. If the RS-
232 interface is detected, then the SM3BAT or SM4BAT FS will continue monitoring
for bats even if the flash cards are full, but no new bat activity data will be recorded.
This condition is indicated by the flash card 100% full indication in the response
messages.

SM3/SM4 FS RS-232 Monitor Interface User Guide
Wildlife Acoustics, Inc. page 7
Bat Activity
Echolocating bats typically produce individual ultrasonic “pulses” continuously
while they fly for navigation, avoiding obstacles, and hunting for food. The
frequencies, bandwidth and duration of pulses varies from species to species and
with the functional needs of the bat at the time (e.g. many bats will increase
bandwidth and decrease duration as they close in on prey).
The SM3BAT or SM4BAT FS can be configured to recognize pulses that may be
tuned to specific bats in a given area. This includes specifying the minimum and
maximum frequencies and minimum and maximum durations of a pulse. These
parameters can be tuned to recognize echolocating bats while avoiding false
positives from other ultrasonic noise sources such as wind, rain, and insects. The
optimum parameters will depend on the specific bats and insects likely occurring in
a given area.
A “bat pass” refers to a series of pulses recorded as a bat flies by the microphone.
Additional parameters in the SM3BAT or SM4BAT FS help define what a bat pass is
including the maximum trigger duration and the maximum time between pulses
(the trigger window). A bat pass begins with the first detected pulse, and ends
when either no pulses have been detected after the maximum time between
pulses has occurred, or when the maximum trigger duration has been reached.
The SM3BAT or SM4BAT FS will not count a bat pass unless it contains at least two
pulses. In this way, the SM3BAT or SM4BAT FS can count passes and pulses
detected on an ongoing basis and report these counts to the customer equipment.
Note: Both the pass and pulse counts are reset if power is cycled, intentionally or from
power source interruption.