This video was very helpful,, I just bought one of these modules from ebay for $7.98, and it came with no datasheet or anything, so thanks again for helping me get started in using it
Hi Martyn, very helpful thanks. I'm trying to switch on and off a solenoid 0-200 times per minute, but not as clever as you guys. I'm guessing this would be part of the solution, if you could point me to another vid to achieve this, that would be even better :)
How could I vary the duty cycle based off a automotive style temp sensor/switch BMW etc? So I could send the preset pwm signal to a fan motor controller.. 128hz or around there is what the controller is set for from factory.
You'd probably be better to use an Arduino rather than this module. For example, this project: www.electroschematics.com/9540/arduino-fan-speed-controlled-temperature/
the output is switched trough a transistor, which gives quite a large peak-peak signal, but due to the high impedance you normally need to output through an amplifier to hear it.
Is it possible to achieve a PWM signal for frequencies less than 1Hz using this module? I have an application which I need a signal pulsed every 30 seconds and was hoping to use this module to do so.
I have a more recent module here that has slightly different commands - F1000 selects 1kHz, F10000 selects 10kHz. The duty cycle command is more flexible also - you can send 'D2' or 'D98' to select 2% or 98% duty cycle. Try these.
HI There, Very good explanation and testing, thank you. can this be set as positive offset frequency? (@4:36 it semms to be positiv offset. am I right?)
Hi Martyn, great video and schematic. I have a question. I’m inputting 8v, but my signal out is only dropping down to around 6 V. That is an oscillation between 8v and 6v. Is there something wrong with my unit or am I doing something wrong.
I haven't encountered that, but I haven't driven the module at more than 5V. I would suspect that the regulator is oscillating, although the 8V looks within its capabilities from the datasheet. You could try putting more capacitance around the regulator, or put a zener in series with it to drop some of the voltage.
@@joedelamo1435 No, not necessarily faulty, but they do try to reduce the bill of materials, e.g. by minimising components and sometimes extra decoupling capacitors can be a help.
It's definitely not designed to be TTL compatible, but will probably work as long as it is run off 5V. Rather than plug it into an expensive piece of equipment, buy a 74xx TTL chip, e.g. 74LS00 and connect the frequency generator to that, make sure that it works and doesn't burn out.
It's the end of the backlight structure, and seems to be where the backlight LED is attached. As far as I can see the backlight is permanently on - it would be nicer if it were controlled by the microcontroller.
thanks.perhaps the power supply could be cut by snipping of the leads to the back light or putting a mini dip switch. i wonder what the power consumption is. the led version used about 18 milliamps at 5volts.
I'm still working on it, Mark. I have an stm8s003 on an evaluation board, and I just built a code sample yesterday to try to understand the on-board UART, and see if there's something obvious that I'm missing about how to use serial. I can't find any further advice online about how to use the serial port on this frequency generator module (other than the same document that's listed on the icstation site). Interestingly, there is also an earlier similar frequency generator (with 2 channels and a different 7-segment display) , which also seems to have problems with the serial interface. I might get one of these also, and see if I can make any progress with that.
Looks Like These are the commands for this PWM module. Cheers Communication Standard: 9600 bps Data bits: 8 Stop bit: 1 Check digit: none Flow control: none 1>. set the frequency of the PWM "F101": Set the frequency to 101 HZ (001 to 999) "F1.05": set the frequency of 1.05 KHZ (1.00 ~ 9.99) "F10.5": Set the frequency to 10.5KHZ (10.0 ~ 99.9) "F1.0.5": set the frequency of 105KHZ (1.0.0 ~ 1.5.0) 2>. set the PWM duty cycle "DXXX": set the PWM duty cycle to XXX; (001 ~ 100) Such as D050, set the PWM duty cycle is 50% 3>. read the set parameters Send a "read" string to read the set parameters. Set successfully return: DOWN; Setup failed to return: FALL.
I bought this one. www.ebay.co.uk/itm/Signal-Generator-PWM-Pulse-Frequency-Duty-Cycle-Adjustable-Module-LCD-3-3V-30V-H/382432921538?_trkparms=aid%3D333200%26algo%3DCOMP.MBE%26ao%3D1%26asc%3D20171012094517%26meid%3D801272f5de3949a484960ac572a0605e%26pid%3D100008%26rk%3D1%26rkt%3D11%26sd%3D391905048325%26itm%3D382432921538%26pmt%3D1%26noa%3D0%26pg%3D2047675&_trksid=p2047675.c100008.m2219
The documentation only talks about integer steps: 2>. set the PWM duty cycle "DXXX": set the PWM duty cycle to XXX; (001 ~ 100) Such as D050, set the PWM duty cycle is 50%
The frequency goes up to 150kHz and actually gives quite a nice square wave at the higher frequencies. According to my oscilloscope, the display reads a little low (1%), so at 100kHz (indicated) my 'scope says 98.9 kHz
Martyn, thank you for the video, is there a chance to wire this frecuency generator as to use it for a motor/electromagnet directly? any help, greatly apleciated
If you look later in the video, it does have a transistor output stage, so it probably can drive a small motor. With inductive loads like motors and electromagnets it's usually a good idea to have a reverse diode across the coil, otherwise otherwise back EMF from the coil will go through the transistor and may damage it (e.g. see electronics.stackexchange.com/questions/110574/how-to-choose-a-flyback-diode-for-a-relay)
The core electronics run off 3.3V, but there is a small voltage regulator on board (you can see it on the upper right at 00:30 in the video when I turn the board over). The specifications say that the max input is 30V, but I personally don't believe that regulator will survive 30V without any kind of heatsink. I'd be reluctant to go over 12V.
In brief, because you need to send the command in a contiguous block of characters and you must not add CR or LF to the end of the command. I show it working in part 3 ( ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-1gkhW2-eBPA.html )
Странное искажение прямоугольного сигнала, в моем обзоре ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-iRD4SNUlzJ8.html , такого не наблюдал. По всей видимости у вас не согласована емкость щупа. Лайк и подписка.