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T249 controlled by 2 quadrature encoders

I’m going to build a power feed(s) for a milling machine and I need to control it both in jog and constant speed modes, both in forward and reverse. I see that the T249 can be controlled via 1 quad encoder connected to 5V, TX and RX pins, but only in speed OR position modes. It seems that there were additional pins that could be set to an encoder (now I can’t find them in the manual) and I was hoping that I could control one encoder at AX, TX for position mode and another at speed mode connected to the mystery pins that are now lost to me. If not, can I control position with an encoder at AX, TX and speed with a potentiometer connected to the SDA/AN pin. I seem to feel the need to control the 5V and switch it from encoder to the other encoder/potentiometer to keep them from accidental simultaneous operation or error.

Please tell me that this is possible because it would save me a ton of chasing my tail to find something else that might work. Yes I know there’s got to be an Android solution but I’m 65 and it’s been 20 years since I’ve done any programming.

Thanks in advance for telling me that it can easily be accomplished with the Tic. If not, curses! B Smith


The Tic only supports connection to one quadrature encoder, so the best solution is probably to get a programmable controller that can read the inputs you want and send appropriate serial or I2C commands to the Tic. If you really do not want to do any of your own programming to process those signals, you could probably get something working by using a multiplexer, a switch, and 3 Tic controllers (two to process the encoders and one to drive the motor). Please let me know if you have any additional questions.


Thanks Brandon, Just to clarify… Would it be possible to use an encoder and also a potentiometer since there appear to be assigned pins for each if I was to use a non short switch to energize 5v to either the encoder or potentiometer, but not both simultaneously? It could even be a joystick with one axis controlling jog and the other axis controlling speed or 2 separate potentiometers. No, I’m not interested in programming. I can do it pretty easily with a DC motor but I’d rather use a stepper if possible. Thanks for the help


The control mode on the Tic would need to be changed for it to switch between responding to an encoder input and responding to an analog voltage input. It is only possible to change the control mode via USB, and configuration settings like this are stored in the Tic’s EEPROM, which is rated for only 100,000 write cycles, so it is probably not practical for your application.

You could use a separate microcontroller such as an Arduino in combination with the Tic. This would allow the Arduino to either read the encoder and potentiometer directly or through the serial/I2C interface on the Tic, then send serial or I2C commands to set the target position or target velocity depending on which input is “active”. However, you would need to write your own program to do this. We have a Tic library for Arduino that can help make the communication easier.