I have a S5D9 IOT board. It is very compact. I want to share my tutorial with the community on how to add ADC capability to the board. I think that it is very useful if the sensor only has an analog output.
In this tutorial, I show 4 examples that covers both r_iic and r_sci_i2c drivers with and without framework. Here is my blog link with source code available.
There are other blogs from me such as adding a distance sensor, a temperature sensor, and a small OLED display that may be useful for your next small project. Feel free to explore them.
Michael, thanks for the great tutorial. When you were working with ADC and DAC, did you have access to an oscilloscope?
I'm looking at buying a super cheap hobbyist DIY kit to at least check the signal. Have you seen the DSO138 kits?
You can get these official kits on Amazon.com for $24.99.
Searching on eBay results in even cheaper clones for $14.98
Here's one example, shipping from the US for $20, free shipping, with the SMD components soldered on.
Here's the specs on it.
Maximum real-time sampling rate : 1MspsAccuracy : 12BitSampling buffer depth : 1024 bytesAnalog bandwidth : 0 - 200KHzVertical Sensitivity : 10mV / Div - 5V / Div ( 1-2-5 progressive manner )Adjustable vertical displacement , and with instructionsInput impedance : 1MΩMaximum input voltage : 50Vpp (1: 1 probe ), 400Vpp (10: 1 probe )Coupling modes include DC / AC / GNDThe horizontal time base range : 10μs / Div - 50s / Div ( 1-2-5 progressive manner )With automatic, regular and one-shot mode , easy to capture the moment waveformAvailable rising or falling edge triggerAdjustable trigger level position , and with instructionsObservable trigger waveform before ( negative delay )Can freeze at any time waveform display (HOLD function )Comes 1Hz /3.3V square wave test signal source
Any opinion on this?
In reply to codetricity:
In reply to Mike:
Michael, thanks for this great information. I noticed that Eric's blog had a screenshot of the Digilent WaveForms software for their o-scopes. He included it in his article on DAC. I went on the Digilent site and saw that the WaveForms software worked with the Digilent Electronics Explorer and the Analog Discovery. I think Eric may have the same Analog Discovery unit that you have. It looks like an excellent piece of equipment. I may get that after I progress. The Analog Discovery looks more portable than the Electronics Explorer and should take up less desk space.
In reply to Jesse Casman:
We just need access to the Analog pins, right?
I've researched more options in the last week. The goal is to find the cheapest equipment that can be used to help with tutorials.
I've ordered a USB Logic Analyzer, which can be purchased for between $9 to $16. Here's a link to Amazon for a $16 unit.
The hardware can be used with Sigrok PulseView
I've researched the cheapest possible oscilloscope units for learning.
Max 200 kHz, single channel.
Standalone, not a USB DSO.
Usable for PWM tutorials for servo (50 Hz) and variable speed DC motors
Usable for audio signals (20 kHz), possibly using microphone
Might be useful for watchdog timer tutorial
Max 48MHz sampling with 20MHz analog bandwidth (claimed), two channels. USB DSO. Community seems somewhat unhappy with software from vendor. possible open source solutions exist.
Can be integrated with open source project Sigrok PulseView. Can replace firmware on boot temporarily with open source version.
Can be used with $5 Android App HScope.
Another open source project called OpenHantek is available.
Another older open source project called BasicScope may also work
Two things about the Rigol DS 1054z
1. There's a promo on until March 31, 2018 that provides the serial decoder and other software with the DS1054z.
2. The popular EEVblog is really keen on the DS 1054z
Based on my current research, I think a good progression for the equipment shown in future tutorials is:
Phase 1: Renesas board and software only, no outside components.
Phase 2: Renesas board and free software with basic components and a multimeter. Assume that person has breadboard, wires, resistors, LEDs.
Phase 3: Show use of cheap $10 logic analyzer with short video or tutorial included with project that explains what the main learning concept such as i2c, SPI, UART does. Tutorial shows open source Sigrok Pulseview as interface
Phase 4: Show use of cheap $20 oscilloscope with project tutorial to illustrate main learning concept such as PWM for servo or variable speed motor control, audio, ADC. Limit max frequency to under 100 kHz
Phase 5: Show use of normal entry bench oscilloscope such as Rigol DS 1054z
Here's the EEVblog video review of the Rigol DS 1054z.