Hi everyone!
So I'd love some feedback on this design I'm working on before going into pcb design.
I have the TC Monitor Pilot, but it only allows for output selection and volume. It's nice and the design with the remote is great, but I'm missing more feeatures. So I'm building a Monitor Assistant (to be accompanied by the Monitor Pilot) with the following features:
I want the same remote + controller design as the TC Monitor Pilot, and in my early tests I had success using a 2 meter USB-C cable to carry power and I2C signals between 2 devices. So that's what I'm planning to use. I've been skeptical about the cable length, and I've read many posts and articles about I2C over longer distances, some saying it would never work, while others say it works fine. I had no problems with my test on the breadboard, which is good.
I'm using an Attiny 814 in the remote device, it's the brain with all the logic. It's connected with 3 buttons, each with 2 LEDs, and I'll add support for single and double press actions to support all features. The controller device is using relays to switch the audio signals controlled by an 8-bit I/O expander (PCF8574) over I2C.
In order to program the remote device, I've included a USB to UPDI converter, using the USB-C plug hardwired to a 2P2T switch switching between programming and I2C signals.
Please don't look close at the power supply, I'm currently planning to use cheaper devices from AliExpress with some filters, but it's not set in stone.
I'm not an experienced designer at all. I have an education in electronics, but I haven't used it in 20 years and I haven't designed anything as complex as this, so there might be obvious problems I'm not seeing. Hence this review request.
What I'm looking for:
Thanks in advance for your time! 🙏
So I'd love some feedback on this design I'm working on before going into pcb design.
I have the TC Monitor Pilot, but it only allows for output selection and volume. It's nice and the design with the remote is great, but I'm missing more feeatures. So I'm building a Monitor Assistant (to be accompanied by the Monitor Pilot) with the following features:
- A/B input
- Mute / Dim
- Solo Mid / Solo Sides (M/S)
- Low pass filter (around 200hz)
- High pass filter (around 10Khz)
I want the same remote + controller design as the TC Monitor Pilot, and in my early tests I had success using a 2 meter USB-C cable to carry power and I2C signals between 2 devices. So that's what I'm planning to use. I've been skeptical about the cable length, and I've read many posts and articles about I2C over longer distances, some saying it would never work, while others say it works fine. I had no problems with my test on the breadboard, which is good.
I'm using an Attiny 814 in the remote device, it's the brain with all the logic. It's connected with 3 buttons, each with 2 LEDs, and I'll add support for single and double press actions to support all features. The controller device is using relays to switch the audio signals controlled by an 8-bit I/O expander (PCF8574) over I2C.
In order to program the remote device, I've included a USB to UPDI converter, using the USB-C plug hardwired to a 2P2T switch switching between programming and I2C signals.
Please don't look close at the power supply, I'm currently planning to use cheaper devices from AliExpress with some filters, but it's not set in stone.
I'm not an experienced designer at all. I have an education in electronics, but I haven't used it in 20 years and I haven't designed anything as complex as this, so there might be obvious problems I'm not seeing. Hence this review request.
What I'm looking for:
- Please check design for obvious faults
- Is there anything that looks weird or wrong?
- The filters are connected with 10-pin connectors, is the layout of the pin order good or problematic?
- Anything else I'm missing or not seeing?
Thanks in advance for your time! 🙏