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piezo-ddr-controller
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switch to 16-bit dumps & add a script for dumping cleaned waveforms 

I can see very clear signal when I:
- tape only the contacts of the sensor to the table, and
- bend the free end into the air, and release (it snaps down)
This commit is contained in:
Colin 2019-12-31 19:29:45 -08:00
parent 2369db3657
commit 609ec60238
2 changed files with 115 additions and 49 deletions
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70
scripts/itm-to-pcm.py Executable file
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@ -0,0 +1,70 @@
#!/usr/bin/env python3
'''
Convert itm.txt dumps to pcm (wave) files
usage: itmdump -f /tmp/itm.txt > dump.txt
itm-to-pcm.py dump.txt dump.wav
'''
import wave
import sys
def read_itm(file_in):
f = open(file_in, 'rb')
while True:
samples = f.read(2)
if not samples: break
#if len(set(samples)) != 1: continue # corrupted
#yield samples[0]
yield samples[0] + 0x100*samples[1]
#for line in f:
# try:
# if line.startswith(b'ADC:'):
# sample = int(line[len('ADC: '):].strip(), 16)
# if sample < 0x1000: yield sample
# except:
# pass
def frames_from_samples(itm):
b = bytearray()
for sample in itm:
sample = (sample + 0x10000) % 0x10000 # counteract Python's signed mod badness
lsb0 = sample % 0x100
lsb1 = (sample // 0x100) % 0x100
b.append(lsb0)
b.append(lsb1)
return b
def clean_frames(frames):
# Run a median filter over the frames to clean outliers:
post_med = [0]*len(frames)
for i, _ in enumerate(frames):
left = max(0, i-2)
right = min(len(frames), i+3)
post_med[i] = median(frames[left:right])
# Remove DC component
dc = sum(post_med) / len(post_med)
post_dc = [f - dc for f in post_med]
# Amplify to [-0x7fff, 0x7fff]
prev_max = max(abs(f) for f in post_dc)
amp_factor = 0x7fff / prev_max
post_amp = [f*amp_factor for f in post_dc]
# Round to int
return [int(round(f)) for f in post_amp]
def median(samples):
x = list(sorted(samples))
return x[len(x) // 2]
def main():
_self, file_in, file_out = sys.argv
itm = clean_frames(list(read_itm(file_in)))
wave_out = wave.open(file_out, 'wb')
wave_out.setnchannels(1)
wave_out.setsampwidth(2)
wave_out.setframerate(1000)
wave_out.writeframes(frames_from_samples(itm))
if __name__ == "__main__":
main()

94
src/main.rs
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@ -232,15 +232,15 @@ fn main() -> ! {
// 0b110 = 181.5 clocks
// 0b111 = 601.5 clocks
per.adc1.smpr1.modify(|_, w| {
unsafe { w.smp1().bits(0b101) };
unsafe { w.smp2().bits(0b101) };
unsafe { w.smp3().bits(0b101) };
unsafe { w.smp4().bits(0b101) };
unsafe { w.smp5().bits(0b101) };
unsafe { w.smp6().bits(0b101) };
unsafe { w.smp7().bits(0b101) };
unsafe { w.smp8().bits(0b101) };
unsafe { w.smp9().bits(0b101) };
unsafe { w.smp1().bits(0b010) };
unsafe { w.smp2().bits(0b010) };
unsafe { w.smp3().bits(0b010) };
unsafe { w.smp4().bits(0b010) };
unsafe { w.smp5().bits(0b010) };
unsafe { w.smp6().bits(0b010) };
unsafe { w.smp7().bits(0b010) };
unsafe { w.smp8().bits(0b010) };
unsafe { w.smp9().bits(0b010) };
w
});
@ -262,48 +262,44 @@ fn main() -> ! {
// We have 48 KBytes of ram
// But sizes >= 4096 seem to cause faults :s
let mut buffer = [0u8; 2048];
loop {
for sample in buffer.iter_mut() {
*sample = (per.adc1.dr.read().bits() >> 4) as u8;
}
itm::write_all(&mut per.itm.stim[0], &buffer);
//let avg_sample = (buffer.iter().map(|x| *x as u32).sum::<u32>() / buffer.len() as u32) as u16;
//if buffer.iter().any(|&s| s as u32 * 4 > avg_sample as u32 * 5 || s as u32 * 5 < avg_sample as u32 * 4) {
// // Dump the buffer:
// itm::write_all(&mut per.itm.stim[0], &buffer);
// //for sample in buffer.iter() {
// ////for i in 0..2048 {
// // //let data = (buffer[i] >> 4) as u32;
// // let data = (sample >> 4) as u8;
// // while !per.itm.stim[0].is_fifo_ready() {}
// // per.itm.stim[0].write_u8(data);
// // //per.itm.stim[0].write_u32(data | (data << 8) | (data << 16) | (data << 24));
// // //delay(10000);
// //}
//}
}
// let mut buffer = [0u8; 1024];
// let mut background_level = 0; // 0 .. 65536
// loop {
// for sample in &mut buffer[..256] {
// *sample = (per.adc1.dr.read().bits() >> 4) as u8;
// }
// let bg_this_iter = buffer[..256].iter().map(|&x| x as u32).sum::<u32>();
// if background_level == 0 {
// background_level = bg_this_iter;
// }
// let thresh = background_level / 230;
// if buffer[..256].iter().any(|&s| s as u32 > thresh) {
// for sample in &mut buffer[256..] {
// *sample = (per.adc1.dr.read().bits() >> 4) as u8;
// }
// itm::write_all(&mut per.itm.stim[0], &buffer);
// //itm::write_all(&mut per.itm.stim[0], &buffer[..1024]);
// //delay(8000000);
// //itm::write_all(&mut per.itm.stim[0], &buffer[1024..2048]);
// //delay(8000000);
// //itm::write_all(&mut per.itm.stim[0], &buffer[2048..3072]);
// //delay(8000000);
// //itm::write_all(&mut per.itm.stim[0], &buffer[3072..]);
// //delay(8000000);
// }
// background_level = (background_level*7 + bg_this_iter) / 8; // LPF
// }
// continuous dump mode (8-bit):
// loop {
// let sample = (per.adc1.dr.read().bits() >> 4) as u8;
// itm::write_all(&mut per.itm.stim[0], &[sample]);
// }
loop {
iprintln!(&mut per.itm.stim[0], "hello!");
}
loop {
//let push_button = per.gpioa.idr.read().idr0().bit();
//let push_button = per.gpiod.idr.read().idr0().bit();
//per.gpioe.odr.modify(|_, w| {
// w.odr8().bit(push_button)
//});
//iprintln!(&mut per.itm.stim[0], "ADC: {:x}", per.adc1.dr.read().bits());
//per.itm.stim[0].write_u32(per.adc1.dr.read().bits());
while !per.itm.stim[0].is_fifo_ready() {}
let adc = per.adc1.dr.read().bits();
//let data = adc as u16;
//per.itm.stim[0].write_u16(data);
let data = (adc >> 4) as u32;
//per.itm.stim[0].write_u8(data);
per.itm.stim[0].write_u32(data | (data << 8) | (data << 16) | (data << 24));
delay(1);
let sample = (per.adc1.dr.read().bits() << 4) as u16;
let high = (sample >> 8) as u8;
let low = (sample & 0xff) as u8;
itm::write_all(&mut per.itm.stim[0], &[low, high]);
}
}