Ned Konz
Program to record speech audio into RAM and then play it back, moving Billy Bass's mouth in sync with the speech.
Remember Big Mouth Billy Bass?
I've made a simple demo program for him using the Freescale FRDM-KL25Z board. I've hooked up the digital I/O to his motor driver transistors and pushbutton switch.
This program records 1.8 seconds of speech audio from ADC input when the pushbutton is pressed, then plays the audio back with Billy Bass's mouth controlled so that it opens during vowel sounds.
The ADC input is driven from a microphone and preamplifier, via a capacitor and into a resistor divider connected to the +3.3V supply pin to provide mid-range biasing for the ADC signals.
The DAC output is connected to his audio amplifier input (to the trace that was connected to pin 10 of the controller IC). I had to provide a DC bias using the DAC to get the single transistor amplifier biased into proper operation.
For more on the method of vowel recognition, please see the paper: http://www.mirlab.org/conference_papers/International_Conference/ICASSP%201999/PDF/AUTHOR/IC991957.PDF
Y. Nishida, Y. Nakadai, Y. Suzuki, T. Sakurai, T. Kurokawa, and H. Sato. 1999.
Voice recognition focusing on vowel strings on a fixed-point 20-MIPS DSP board.
In Proceedings of the Acoustics, Speech, and Signal Processing, 1999. on 1999 IEEE International Conference - Volume 01 (ICASSP '99), Vol. 1. IEEE Computer Society, Washington, DC, USA, 137-140. DOI=10.1109/ICASSP.1999.758081 http://dx.doi.org/10.1109/ICASSP.1999.758081
Diff: FastAnalogIn.h
- Revision:
- 1:2fa375aacece
- Child:
- 2:5bcd2f55a294
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/FastAnalogIn.h Tue May 14 14:08:22 2013 +0000
@@ -0,0 +1,52 @@
+#ifndef __included_fast_analog_in_h
+#define __included_fast_analog_in_h
+
+#include "mbed.h"
+
+namespace NK
+{
+
+using namespace mbed;
+
+class FastAnalogIn: public mbed::AnalogIn
+{
+public:
+ void start_read() {
+ ADC0->SC1[0] = ADC_SC1_ADCH(_adc.adc); // start conversion
+ }
+
+ uint16_t read_u16() {
+ // Wait Conversion Complete
+ while ((ADC0->SC1[0] & ADC_SC1_COCO_MASK) != ADC_SC1_COCO_MASK);
+
+ // Return value
+ return (uint16_t)ADC0->R[0];
+ }
+
+ FastAnalogIn(PinName what)
+ : mbed::AnalogIn(what) {
+ ADC0->CFG2 = /* ADC_CFG2_MUXSEL_MASK // ADxxb channels are selected */
+ 0 | ADC_CFG2_ADACKEN_MASK // Asynchronous Clock Output Enable
+ | ADC_CFG2_ADHSC_MASK // High-Speed Configuration
+ | ADC_CFG2_ADLSTS(0); // Long Sample Time Select = 24 clocks
+
+ // set up for averaging 16 samples at 125KHz sample rate => 7812.5 samples/sec
+ ADC0->SC3 = ADC_SC3_AVGE_MASK // Hardware Average Enable
+ | ADC_SC3_AVGS(2) // 16 Samples Averaged
+ | ADC_SC3_ADCO_MASK; // contin conversion
+ }
+
+ void enable_interrupt() {
+ ADC0->SC1[0] |= ADC_SC1_AIEN_MASK; // enable interrupt
+ ADC0->SC1[1] |= ADC_SC1_AIEN_MASK; // enable interrupt
+ }
+ void disable_interrupt() {
+ ADC0->SC1[0] &= ~ADC_SC1_AIEN_MASK; // disable interrupt
+ ADC0->SC1[1] &= ~ADC_SC1_AIEN_MASK; // disable interrupt
+ }
+
+};
+
+}
+
+#endif
\ No newline at end of file