MIDIbox MF MotorFader NG PCB

The MF_NG module is the successor of the MBHP_MF module and has following design targets:

• find a solution to handle high-quality faders like Alps K faders with "coreless" motors
• find a solution for MBHP_CORE_LPC17 which doesn't deliver stable enough ADC conversion results due to the reduced 3.3V voltage range
• find a solution for MBHP_CORE_LPC17 which cannot handle touch sensors properly without heavy CPU load (resp. without an additional external device or microcontroller)
• find a solution which is compatible with PIC based projects for best usability
• find a solution which is DIY friendly and doesn't require additional gear for something which isn't part of the MBHP yet
• find a solution which can be easily tested and troubleshooted (no need to learn new processes)

And this module is the result:

• a dedicated PIC controller controls the motorfaders directly.
• the firmware can be updated via MIDI!
• motorfaders are accessed via MIDI - this allows standalone usage, cascading (to chain multiple modules), and the re-use of existing infrastructure such as MIOS, MIOS Studio and MIOS Bootloader
• the module can either be connected to a PC directly, or controlled from a second PIC or STM32 or LPC17 (note that MBHP_CORE_LPC17 has a third and even a fourth MIDI IO port at TTL level so that the available two MIDI IO pairs are still free)
• native support of various protocols (e.g. PitchBender, CCs, even Logic Control and Mackie Control Emulation)
• support for 8 touch sensors
• instead of TC4427 I'm using L293D now - not at least because of the integrated diodes.
• due to the direct motor control connections, the PIC is now able to generate PWM with 50 uS steps for improved motor speed control while a motor is moved
• since the firmware is dedicated for this task, there was enough memory free to integrate advanced features, such as runtime-calibration and motor position tracing which are supported by MIOS Studio: