User manual

The on-board offload utility and the high-speed MMP Unpacker application cannot
support non-standard sensor settings. Processing binary data files collected with non-standard
sensor settings is the responsibility of the operator. The firmware can automatically verify
standard sensor settings at the beginning of a deployment or allow the operator to manually
program the sensors. Contact McLane if programming non-standard sensor settings is required
for a deployment.
Other Sensors
Other sensors can be added to the MMP. Integrating non-standard sensors requires a
partnership with McLane.
NOTE
Information about Seabird Sensors is provided in Appendix , of this User Manual “Seapoint
Analog Sensors”.
Many biogeochemical sensors are direct reading instruments without the autonomous
internal logging capability of the CTD and the ACM. In a typical implementation the output of
such an instrument is digitized each time a record of engineering parameters is assembled and the
measurement is added to the engineering record.
Five analog-to-digital (A/D) channels are available on the motherboard’s
ANALOG
connector for instrument connection. Each channel can accept a 0.0 V to 4.096 V input and
digitize it to 12-bit (1 mV) accuracy. The 4.096 V limitation is a characteristic of the A/D
converter of the TT8v2. Unfortunately, analog sensors with a 0 V to 5 V output are the norm.
Fortunately, voltages greater than 4.096 V will not damage the MMP electronics, however, the
output of the A/D conversion will be 4.096 V. In these cases the sensor output can be scaled on
the MMP motherboard to fall into the allowed range. The system’s analog ground and a
reference voltage generated by the A/D are both accessible on the connector.
Two DIO channels (0 V and 5 V) are available on the motherboard
FREQUENCY
connector for instrument connection. Both channels can be programmed as counters to
accommodate sensors with frequency outputs (e.g., quartz pressure transducers). They can also
serve as simple logic inputs. Alternatively, the channels can be configured as outputs and used to
control sensor parameters such as gain.
Appendix B-11