AIN range change

[gm02froe]

Hi

is there a way to change the voltage range (instead of 0V...5V -> 0.4V...5V) that is translated into 127...0 values?

[audiocommander]

http://www.midibox.org/forum/index.php?topic=10056.msg74922#msg74922

else see the ACSensorizer, it's a specialized application for up to eight sensory devices delivering not exactly 0..5 V

An inverted signal is supported as well (127..0)

http://www.midibox.org/dokuwiki/acsensorizer_04

Best,

Michael

[gm02froe]

thank you for the hints. I solved it the following way:

unsigned char Math_Scale10BitTo7Bit(unsigned int v, unsigned int min10Bit, unsigned int max10Bit, unsigned char min7Bit, unsigned char max7Bit) __wparam
{
	// scales an 7-bit (0-255) value between min & max
	unsigned char scaled = 0;
	unsigned long promille;
	if(min7Bit <= 0){min7Bit = 0;}
	if(max7Bit > 127){max7Bit = 127;}
	if(min10Bit <= 0){min10Bit = 0;}
	if(max10Bit > 1023){max10Bit = 1023;}

	if(min10Bit <= v && v < max10Bit && min7Bit < max7Bit){
		promille = (unsigned long)(v);
		promille = (promille - min10Bit) * 1000 / (max10Bit - min10Bit);
		scaled = (max7Bit - min7Bit + 1) * promille / 1000 + min7Bit;
	}else if(min10Bit > v){
		scaled = min7Bit;
	}else if(max10Bit <= v){
		scaled = max7Bit;
	}
	return scaled;
}

this way I can call the method like this:

void AIN_NotifyChange(unsigned char pin, unsigned int pin_value) __wparam
{
  // a pot has been moved, send CC#<pin-number> at channel 1
  MIOS_MIDI_BeginStream();
  MIOS_MIDI_TxBufferPut(0xb0); // CC at channel 1
  MIOS_MIDI_TxBufferPut(pin);  // pin number corresponds to CC number
  MIOS_MIDI_TxBufferPut(Math_Scale10BitTo7Bit(MIOS_AIN_PinGet(last_ain_pin), AIN_10BITMIN, AIN_10BITMAX, AIN_7BITMIN, AIN_7BITMAX));
   MIOS_MIDI_EndStream();

  // notify display handler in DISPLAY_Tick() that AIN value has changed
  last_ain_pin = pin;
  app_flags.DISPLAY_UPDATE_REQ = 1;
}

and not to forget:

AIN_DEADBAND  = 5 (I dont really understand how deadband really works, this value is experimental)

plus http://www.ucapps.de/mios/mios_libsdcc_v2_5_0.zip - which is the library for my humble java-like calculations.

[audiocommander]

Hi t0gg1e4u,

although your code seems mathmatically correct, one should add that the heavy use of unoptimized divisions (and to some extend multiplications) may introduce various codesize and timing problems;

surely not if you just turn slowly one knob at a time, but I'd expect strange behaviours under heavy load (many quick changes on multiple inputs).

Please understand this as a final comment: if it works for you, it should be fine  ;)

Best,

Michael