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ainser64_module [2016/07/11 16:20]
psykhaze created
ainser64_module [2016/08/04 09:43] (current)
psykhaze
Line 1: Line 1:
 ====== AINSER64 Module ====== ====== AINSER64 Module ======
 +
 +{{ :​neonking:​mbhp_ainser64.jpg?​400 |}}
 +
 +===== Introduction =====
 +
 +MBHP_AINSER64 is the successor of the MBHP_AIN module, and **//only supported by MIOS32!//
 +\\
 +\\
 +It is based on the 8-channel ADC MCP3208** from Microchip and **8x4051 multiplexers** so that up to **64 analog inputs** are available. They can be used to scan pots and/or faders with 12bit resolution between 0 and 5V..**The accuracy and especially the signal/​noise ratio is much better compared to the internal ADCs of STM32** for insignificantly higher costs (around 3 EUR).
 +\\
 +\\
 +Another advantage is the **Improved Scalability**. While with the previous MBHP_AIN module the maximum number of scannable inputs was limited by the number of on-chip ADC channels, **the new approach allows to access multiple MBHP_AINSER64 and MBHP_AINSER8 modules from the same microcontroller.The ADC is accessed via SPI** (e.g. J19 of the MBHP_CORE_STM32F4 module).
 +\\
 +\\
 +Multiple MBHP_AINSER8 (or MBHP_AINSER64) modules are connected to J19 in parallel, and accessed by strobing dedicated chip select lines. J19 provides two chip selects (called "​RC1"​ and "​RC2"​),​ if more modules should be scanned, common IO pins could be used for the same purpose (e.g. available at J5). Alternatively,​ AINSER* modules could be chained, or a 3-to-8 MUX could be used for accessing 8 modules via 3 IO pins of the microcontroller.
 +\\
 +\\
 +**Accuracy**:​ the on-chip ADCs of STM32 are jittering by at least +/- 16. Accordingly,​ the effective resolution which can be used for MIDI controller purposes is 10 bit. Such a high resolution is especially useful for PitchBender and NRPN messages.
 +\\
 +\\
 +**Powering the module via USB (provided at J19 by the core module) is sufficient**. It's recommended to use a "​selfpowered"​ USB Hub like this one from Reichelt. It also decouples the power from the (noisy) PC supply, and allows to run the MIDIbox without a PC connection.
 +\\
 +
 +===== Parts List / Schematic =====
 +
 +See [[ainser64_board_parts_list|AINSER64 Parts List]]
 +\\
 +  * {{http://​ucapps.de/​mbhp/​mbhp_ainser64.pdf|Schematic}}<​sup>​UCapps</​sup>​
 +
 +
 +===== Inputs/ Outputs Port Table =====
 +
 +^ Port ^ Pins # ^ Description ​                                                                           ^
 +| J2   | 10     | Serial input which is usually connected to J19 of MBHP_CORE_STM32F4 module. ​           |
 +| J3   | 10     | Serial output which could be used to chain multiple MBHP_AINSER* modules.**Please note: the standard AINSER driver for MIOS32 doesn'​t support this method!** Instead it expects that multiple modules are connected to J19 in parallel, and that they are using dedicated chip select lines (selected via jumper J4)!        |
 +| J4   | 3      | A jumper has to be connected to this port to select the first or second chip select line of J2 for accessing the ADC.  |
 +|J6-J13| 10     | 8x8 analog inputs and 5V (=Vd) / Ground (=Vs) connections.**Please note: all unused analog inputs have to be clamped to ground (Vss)**, otherwise your MIDIbox will send out a lot of random MIDI events |
ainser64_module.txt ยท Last modified: 2016/08/04 09:43 by psykhaze