# Another UART Module **URL:** \ **Category:** Expansion Card\ **Created:** [June 2, 2022, 3:58pm UTC](https://community.frame.work/t/another-uart-module/19177 "2022-06-02T15:58:14Z")\ **Posts on this page:** 8\ **Page:** 1
**Author:** ![Luke\_Paulson](https://sea1.discourse-cdn.com/flex001/user_avatar/community.frame.work/luke_paulson/32/9211_2.png) [@Luke\_Paulson](https://community.frame.work/u/Luke_Paulson)\ **Post date:** [June 2, 2022, 3:58pm UTC](https://community.frame.work/t/another-uart-module/19177/1 "2022-06-02T15:58:14Z")
I’m working on a serial communication module that should bring out I2C, SPI, UART, and JTAG and support the most common voltage levels. Unforturnelty, because of a design error, the level shifting circuit isn’t working. So far, the UART is confirmed working, so that’s a good enough reason to start working on REV2. Eventually, it would be amazing to have a set of modules geared towards electronics/embedded development; I see someone is already working on a [Logic Analyzer](http://community.frame.work/t/logic-analyser-work-in-progress) ![PXL_20220602_025049975](https://us1.discourse-cdn.com/flex001/uploads/framework3/original/2X/c/c268d307a7c992b1e3e46897772e27661277e01b.jpeg) There are a few more pictures on the [insta](https://instagram.com/castrlab/) ---
**Author:** ![nrp](https://sea1.discourse-cdn.com/flex001/user_avatar/community.frame.work/nrp/32/352_2.png) [@nrp](https://community.frame.work/u/nrp)\ **Post date:** [June 5, 2022, 9:49pm UTC](https://community.frame.work/t/another-uart-module/19177/2 "2022-06-05T21:49:25Z")
Awesome work! Connector selection is definitely a tricky one for this sort of card. We found a 0.1" pitch connector that just barely fits, that we put on the Microcontroller reference design. ---
**Author:** ![Luke\_Paulson](https://sea1.discourse-cdn.com/flex001/user_avatar/community.frame.work/luke_paulson/32/9211_2.png) [@Luke\_Paulson](https://community.frame.work/u/Luke_Paulson)\ **Post date:** [June 11, 2022, 7:15pm UTC](https://community.frame.work/t/another-uart-module/19177/3 "2022-06-11T19:15:14Z")
To get a better fit, I dropped to 50mil (1.27mm) pitch; this makes it easier to sandwich the board between the two rows. I made a bit more progress on the module; I made some board-level repairs and got the indications and level shiting circuitry to work. Now I can change the serial comm level to 5V, 3.3V and 1.8V, and the indicator LED. At this point, revision two looks like a production-level device. The next big thing I need to work on is creating a configuration tool that will allow me to configure the device and provide a terminal or somthing to use the various communication protocols. That’ll be the hard part for me… There’s slightly better video on Instagram ![ezgif.com-gif-maker(3)](https://us1.discourse-cdn.com/flex001/uploads/framework3/original/2X/3/3f275ec3f54e28c856a6ac9637856104235bd7fb.gif) ---
**Author:** ![noname](https://avatars.discourse-cdn.com/v4/letter/n/58f4c7/32.png) [@noname](https://community.frame.work/u/noname)\ **Post date:** [August 15, 2022, 10:34am UTC](https://community.frame.work/t/another-uart-module/19177/4 "2022-08-15T10:34:29Z")
Do you have a GitHub repository for the schematics? ---
**Author:** ![Luke\_Paulson](https://sea1.discourse-cdn.com/flex001/user_avatar/community.frame.work/luke_paulson/32/9211_2.png) [@Luke\_Paulson](https://community.frame.work/u/Luke_Paulson)\ **Post date:** [August 18, 2022, 12:15am UTC](https://community.frame.work/t/another-uart-module/19177/5 "2022-08-18T00:15:39Z")
I do, but I’m not ready to release it publicly yet, there are still a couple bugs. I will more likely make available pdf of the schematics. The code will probably be open source when it’s ready. ---
**Author:** ![noname](https://avatars.discourse-cdn.com/v4/letter/n/58f4c7/32.png) [@noname](https://community.frame.work/u/noname)\ **Post date:** [August 18, 2022, 11:22am UTC](https://community.frame.work/t/another-uart-module/19177/6 "2022-08-18T11:22:26Z")
> [@Luke\_Paulson](#): > > I will more likely make available pdf of the schematics I hope that is enough for me haha. I am really new to the whole designing own electronics hobby. On the other hand it might be a cool little exercise to turn the PDF into a proper Gerber file. ---
**Author:** ![Luke\_Paulson](https://sea1.discourse-cdn.com/flex001/user_avatar/community.frame.work/luke_paulson/32/9211_2.png) [@Luke\_Paulson](https://community.frame.work/u/Luke_Paulson)\ **Post date:** [August 18, 2022, 3:57pm UTC](https://community.frame.work/t/another-uart-module/19177/7 "2022-08-18T15:57:01Z")
If your looking for a base project, you should checkout frameworks expansion module repo. If you need any help with the electronics or PCB development feel free to drop me a private message. > **[GitHub - FrameworkComputer/ExpansionCards: Reference designs and documentation to create...](https://github.com/FrameworkComputer/ExpansionCards)** > > Reference designs and documentation to create Expansion Cards for the Framework Laptop ---
**Author:** ![Luke\_Paulson](https://sea1.discourse-cdn.com/flex001/user_avatar/community.frame.work/luke_paulson/32/9211_2.png) [@Luke\_Paulson](https://community.frame.work/u/Luke_Paulson)\ **Post date:** [February 15, 2023, 5:25pm UTC](https://community.frame.work/t/another-uart-module/19177/8 "2023-02-15T17:25:42Z")
I’ve just finished building the second revision of the module, which is more or less a complete redesign. The original serial bridge wasn’t going to do what I needed, so I’m going the MCU route. The plan is to have all the same functionality as the original module, but the MCU should allow some other nifty features; I’d say this is a pretty similar idea to the Bus Pirate. At this point, the board powers up and accepts firmware. Now I need to write the firmware… again. I did a little blog [post](https://castrlab.com/electronics/2023/02/14/Framework-Expansion-Module.html) about the general design choices and included the Gitlab link if anyone was interested in helping out or had any suggestions. This is all taking longer than expected since it’s a side project; bear with me.