- 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 (e.g. chip programmer) 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)
Following circuit is the result: http://www.ucapps.de.../mbhp_mf_ng.pdf
- a dedicated PIC controller controls the motorfaders directly
- it can be accessed via MIDI (only) - 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
Two snapshots of the prototype - currently I've only tested the circuit with high-quality K Faders, which were not properly controllable with MBHP_MF_V1
Meanwhile PCBs are available (layout created by SmashTV - thank you!!! )
MIOS Studio got a new configuration tool:
Especially the calibration is much easier now, not at least because of the new motor position tracing feature:
Currently following modes are planned:
- PitchBender Chn#1..#8
- PitchBender Chn#9..#16
- CC#07 Chn#1..#8
- CC#07 Chn#9..#16
- CC#16..#23 Chn#1
- CC#24..#31 Chn#1
- Faked Logic Control
- Faked Logic Control Extension
- Faked Mackie Control
- Faked Mackie Control Extension
There is no real need to add more modes, considered that MIDI events can be mapped on the host PC and/or from another microcontroller (like Core32) which uses MBHP_MF_V3 as a companion.
By using Pitchbender events, the highest resolution (10bit) is available.
More about this topic (e.g. test of different motorfaders) after holidays.
Best Regards, Thorsten.