Hey Team! I've got a question on if Workstation can/does support the following products: Bellingham + Stanley RFM712-M Digital Refractometer Metrohm 913 pH meter Digital thermometer (Bluetooth) (*don't have a make/model for this one, just the technology) I understand we send messages back and forth to the instruments, but what would the instrument need to communicate to us? (edited)
asked
Jeff Mierzwa
1 answers
1
Hey Jeff,
The refractometer has both a serial and a tcp interface, so you should be able to communicate with it that way. You would just need to determine its message format from its documentation or via trial and error
From my initial research, it looks like the Metrohm pH meter is exposed to Windows as an external drive containing CSV files that have the latest measurements. The data would be readable using a File device and can be parsed in Mendix. It looks like you are not able to trigger a measurement programmatically. It has to be done via the button on the device.
Regarding bluetooth digital thermometers, ideally you would choose a BLE device that exposes the temperature via a GATT characteristic. Most BLE (bluetooth low energy) thermometers do it this way, though some don't follow the GATT specification, which makes it harder to communicate with. If you have a device that follows the specification, then you can simply subscribe to the temperature characteristic, and you will receive a message in your Mendix app whenever the temperature reading changes. See the docs for the message to send to subscribe to a characteristic.