I2C communication USB to I2C converter - Page 1
Forum section: electronics / projects

author: Nikos A.
author_rank: Regular Contributor
timestamp: September 01, 2020, 12:43:24 pm
content: Hi everyone,I am designing a board that incorporates the bq27421 battery gauge. Reading this Application Reporthttps://www.ti.com/lit/an/slua790/slua790.pdf?ts=1598963347236&ref_url=https%253A%252F%252Fwww.google.com%252F, the author uses an I2C master control panel (see pg3) to communicate with the slave.That seems really convinient before starting developing the firmware.I suppose that this requires a USB to I2C converter something like thishttps://learn.adafruit.com/adafruit-ft232h-breakout/overviewisn't it? Also, I believe is required some kind of software to run the I2C control panel.. So I want to ask if someone has to recommend any PC based I2C master tool to interact with I2C slaves.ThanksNick

author: HB9EVI
author_rank: Frequent Contributor
timestamp: September 01, 2020, 01:15:07 pm
content: https://github.com/harbaum/I2C-Tiny-USBworks reliably but not very fastotherwise: MCP2221simple to use and faster; a plus is, that it doesn't require any external components like a crystal; although I haven't done any longtime test so far;

author: jhenderson0107
author_rank: Regular Contributor
timestamp: September 01, 2020, 01:23:08 pm
content: I have this one and it works well:https://www.crowdsupply.com/excamera/i2cdriver

author: madires
author_rank: Super Contributor
timestamp: September 01, 2020, 01:39:01 pm
content: Arduino, BusPirate, RasPi, ... anything with an MCU and an USB port.

author: magic
author_rank: Super Contributor
timestamp: September 01, 2020, 01:47:04 pm
content: Any VGA/DVI/HDMI output contains an I2C master but it takes software to use it.Very easy on Linux.

author: rvalente
author_rank: Frequent Contributor
timestamp: September 01, 2020, 04:09:40 pm
content: Bus pirate, can't think of anything easier.Plug it, open a terminal, done!

author: ebclr
author_rank: Super Contributor
timestamp: September 01, 2020, 11:36:26 pm
content: https://www.onetransistor.eu/2017/09/ch341a-usb-i2c-programming.htmlhttps://pt.aliexpress.com/item/32516648608.html?spm=a2g0o.productlist.0.0.751f528apVP4Rj&algo_pvid=81a95aef-2358-416a-8c02-087575f3d637&algo_expid=81a95aef-2358-416a-8c02-087575f3d637-8&btsid=0ab6d59515990033223611820e8e91&ws_ab_test=searchweb0_0,searchweb201602_,searchweb201603_

author: Scrts
author_rank: Frequent Contributor
timestamp: September 02, 2020, 12:43:34 am
content: I've used Bus Pirate for hobby use, which is great if you send a single command here and there.And we use TotalPhase stuff for work:https://www.totalphase.com/products/aardvark-i2cspi/,which has single/group command mode as well as bulk/script send/receive plus EEPROM read/write app.

author: Nikos A.
author_rank: Regular Contributor
timestamp: September 02, 2020, 09:00:20 am
content: Thank you all for your inputs!! Bus Pirate looks like a great option, that was exactly what I was lookign for!!!!Thanks!!

author: evac
author_rank: Contributor
timestamp: September 02, 2020, 09:24:34 am
content: Quote from: HB9EVI on September 01, 2020, 01:15:07 pmThe I2C-tiny has worked pretty well for me.Perhaps not the best suited for your specific application, but one big advantage at least for me is that there is Linux kernel module for it which creates a new bus in the kernel I2C subsystem.This means that you can leverage existing kernel modules for I2C devices instead of having to write your own.E.g. if you connect say an LM45 sensor to the I2C-tiny, it will be natively recognized in Linux and show up in lm_sensors and other monitoring utilities.Even the bq27421 has a Linux driver, so you could connect it and it should show up as a battery.