Search found 1398 matches

by Pito
Thu Aug 24, 2017 8:22 am
Forum: Projects
Topic: HB100 Radar speed detector
Replies: 8
Views: 80

Re: HB100 Radar speed detector

Roger, I would guess you will not be happy with your measurements unless you wire the amplifier as on the schematics above. The useful (your beat) output signal from the module is in range of uV, and only up to couple of hundreds Hertz of frequency. You have to consider that. Doppler shift output fr...
by Pito
Thu Aug 24, 2017 7:53 am
Forum: Projects
Topic: HB100 Radar speed detector
Replies: 8
Views: 80

Re: HB100 Radar speed detector

Best you would use 2 modules in series (each with 1Meg feedback). Mind the coupling capacitors (C2) should be bigger. Also remove the R2. C4=100pF - with that capacitor and 1Meg the upper corner freq will be maybe 2kHz, thus you will get a lot of noise. Your beat signals are up to say 200Hz, so I wo...
by Pito
Thu Aug 24, 2017 7:42 am
Forum: Projects
Topic: HB100 Radar speed detector
Replies: 8
Views: 80

Re: HB100 Radar speed detector

With that MAX module you have to remove the R2 resistor when connected to the radar output (leave the 12k at the module's output there). With R5=1k you get gain=100, with R5=100ohm you get gain=1000, etc. Also I would increase the C2 to something like 1uF (ceramic/foil) to move down the input's high...
by Pito
Thu Aug 24, 2017 6:51 am
Forum: Projects
Topic: HB100 Radar speed detector
Replies: 8
Views: 80

Re: HB100 Radar speed detector

The second opamp is an amplifier too, with gain about 120, the 2.2nF creates a low pass filter in both (corner freq is aprox 74Hz -6dB). The 4.7uF and 10k creates high pass corner aprox 3.5Hz. So in total the gain is aprox 100 x 120 = 12000 (inside a bandpass 3-75Hz). With none signal at the input (...
by Pito
Wed Aug 23, 2017 5:10 pm
Forum: STM32F103 Boards
Topic: AttachInterrupt for STM32F103
Replies: 12
Views: 5182

Re: AttachInterrupt for STM32F103

How did you measure the 5-10us interrupt latency?
by Pito
Wed Aug 23, 2017 8:03 am
Forum: Black Magic Probe & other
Topic: J-Link EDU Mini $18
Replies: 12
Views: 149

Re: J-Link EDU Mini $18

@pito Have you tried it ? I tested this on 2 different types of "dongle" and it would not install on either @Roger: As I wrote above you need a small fw mod, but no idea how to do it.. http://www.stm32duino.com/viewtopic.php?f=3&t=1448#p18757 UPDATE: tried here (for my educational purpose only) and...
by Pito
Wed Aug 23, 2017 6:39 am
Forum: Black Magic Probe & other
Topic: J-Link EDU Mini $18
Replies: 12
Views: 149

Re: J-Link EDU Mini $18

Segger offers ST-Link conversion to J-Link since spring '16..
Works with ST-Link clones (dongles) too (a tiny sw mod is needed afaik).
Has been tested by someone here and it works..
https://www.segger.com/products/debug-p ... -on-board/
by Pito
Tue Aug 22, 2017 4:48 pm
Forum: STM32generic
Topic: [STM32GENERIC/HAL] SerialUSB TX/RX speed problem
Replies: 69
Views: 1251

Re: [STM32GENERIC/HAL] SerialUSB TX/RX speed problem

Because of 3secs between the packets when the bufsize in the sketch is 256bytes (or 512, 1024 etc).. That is even visible in TT as the 4kB chunks always nap for 3secs.. Another test - counting bytes - logged into TT file. To make it simple I've TXed 1.280.000 bytes #define bufsize 64 #define TXCHARS...
by Pito
Tue Aug 22, 2017 1:52 pm
Forum: STM32generic
Topic: [STM32GENERIC/HAL] SerialUSB TX/RX speed problem
Replies: 69
Views: 1251

Re: [STM32GENERIC/HAL] SerialUSB TX/RX speed problem

Problem: STM32Generic with CDC_BUF 128, and bufsize = 256 (speed ???) 3seconds between packets STM32Generic CDC_BUFF 128 bufsize 256.JPG And STM32Generic with CDC_BUF 4096, and bufsize = 64 (speed 420kB/sec) STM32Generic CDC_BUFF 4096 and bufsize 64.JPG STM32Generic with CDC_BUF 4096, and bufsize = ...
by Pito
Tue Aug 22, 2017 1:19 pm
Forum: STM32generic
Topic: [STM32GENERIC/HAL] SerialUSB TX/RX speed problem
Replies: 69
Views: 1251

Re: [STM32GENERIC/HAL] SerialUSB TX/RX speed problem

This is with MMini, Libmaple F1, with this vitor_boss' mod of my sketch (Serial.write(buf..): void loop() { uint32_t i; uint8_t x = 85; uint32_t elapsed = micros(); uint8_t buf[bufsize]; for (i = 0; i < bufsize; i++) { buf[i] = x; } elapsed = micros(); for (i = 0; i < TXCHARS; i+=bufsize) { Serial.w...