Hi all, new to the forum, thank you for any guidance you can provide.
I am trying to get the Teensy 4.1 to interface automatically with an Ohaus AR3130 scale via its RS 232 port. I am using a Max3232 converter board to convert the RS232 levels to 3.3 TTL levels. The scale can send values over the RS 232 port by manually pressing the "Print" button, or by sending "P" to it's RX channel. The scale can also be tared remotely by sending "T". To get the system working, I am using the "T" as a test command because it is easy to check the scale display to see if it has been tared.
The system behaviour is unstable. Using a logic analyzer, I have been able to read the "T" that I have remotely sent at the RX channel of the scale. However, this has been intermittent, and random. (ie, if I disconnect and reconnect the logic analyzer probe, I can no longer read anything I send. It can also be disrupted by other events, like unplugging and replugging the RS 232 connector.
RX readings at the Teensy, seem to be OK. However, if I configure the Teensy serial port with Serial(9600,SERIAL_8N1_RXINV), it starts streaming readings. I use the Invert logic configuration because that's what seems to decode the data properly.
TX readings at the Teensy, and at the RX channel of the scale. As mentioned earlier, sometimes I can read at the scale, and sometimes I can not.
Even when the "T" was sent correctly, it still did not tare the scale. Looking at the scale manual, the approach I am taking seems to be correct. Any insight would be hugely appreciated.
I am trying to get the Teensy 4.1 to interface automatically with an Ohaus AR3130 scale via its RS 232 port. I am using a Max3232 converter board to convert the RS232 levels to 3.3 TTL levels. The scale can send values over the RS 232 port by manually pressing the "Print" button, or by sending "P" to it's RX channel. The scale can also be tared remotely by sending "T". To get the system working, I am using the "T" as a test command because it is easy to check the scale display to see if it has been tared.
The system behaviour is unstable. Using a logic analyzer, I have been able to read the "T" that I have remotely sent at the RX channel of the scale. However, this has been intermittent, and random. (ie, if I disconnect and reconnect the logic analyzer probe, I can no longer read anything I send. It can also be disrupted by other events, like unplugging and replugging the RS 232 connector.
RX readings at the Teensy, seem to be OK. However, if I configure the Teensy serial port with Serial(9600,SERIAL_8N1_RXINV), it starts streaming readings. I use the Invert logic configuration because that's what seems to decode the data properly.
TX readings at the Teensy, and at the RX channel of the scale. As mentioned earlier, sometimes I can read at the scale, and sometimes I can not.
Even when the "T" was sent correctly, it still did not tare the scale. Looking at the scale manual, the approach I am taking seems to be correct. Any insight would be hugely appreciated.