New product: A-Star 328PB Micro

Posted by Jan on 20 February 2018

Today we are releasing our newest A-Star programmable controller, the A-Star 328PB Micro. It is basically our version of the ubiquitous Arduino Pro Mini type products, but with the newer ATmega328PB microcontroller. The board itself is pretty straightforward (though the updated AVR is exciting), so the main thing I want to share in this post is our history with the Atmel ATmega328PB microcontrollers (this was before Microchip acquired Atmel) and how this product would not have existed without our lower-cost manufacturing initiative that I have been discussing.

We have been using the ATmega8, and then the ATmega48, ATmega168, and ATmega328P, since 2004 in many of our user-programmable products because of their versatility and excellent free compiler support (which also made Arduino possible). We first heard about the ATmega328PB in early 2014. The product kept being delayed, and I did not get a quote for them until October 2015. I ordered a reel right away; it arrived in March 2016. Over those two years, we put our AVR-related efforts into the ATmega32U4, releasing several A-Star 32U4 programmable controllers and using it on robots like the Zumo 32U4. The ATmega32U4 was a superior part with native USB and more I/O lines, making it a better fit for many of our applications. By the time we finally got the ATmega328PB parts, we had the A-Star 32U4 Micro available for just $12.75, making it less exciting to put effort into a lower-performance product that might end up costing almost the same amount.

Original ATmega168-based Baby Orangutan robot controller from 2005 (left) next to A-Star 32U4 Micro boards.

The new manufacturing equipment I ordered in the fall of 2017, along with the availability of our latest AVR programmer, brought attention back to the feasibility of a basic ATmega328PB carrier. I was hesitant to put effort into a product where we could not offer something substantially more compelling than what was already available. Despite the ATmega328PB being out in the wild for almost two years, it still had not really made it into many Arduino products, so I thought that perhaps we could offer something there. But more importantly, I wanted to see how low we could price it. I was aware of Arduino Pro Mini clones available on eBay and the AliExpress-type sites for under $3. Most official Arduino Pro Mini type products cost more like $10. For this project to be worthwhile, I wanted to get under $5.

It turns out we had to squeeze quite a bit just to get to the upper limit of that “under $5” goal, and so we are releasing this product at a unit retail price of $4.95. It’s not the under-$3 you can find for the absolute cheapest clones, but if you get the A-Star 328PB Micro from us, you are getting a well-supported, well-made product (each unit is 100% automatically visually inspected and 100% functionally tested) and supporting a company that is doing more than just copying products that are already out there.

It is my hope that by being able to offer the A-Star 328PB Micro for under $5, we are offering something meaningful, giving you a new option for general-purpose controllers at the price of a cheap lunch. I am interested to hear what you think. Is the 328PB interesting when you can get USB for not much more? Is the price low enough for you to buy from us instead of getting it from China?

We are offering the A-Star 328PB Micro in four voltage and frequency combinations:

A-Star 328PB Micro pinout diagram.

The A-Star 328PB Micro provides access to all 24 I/O lines of the microcontroller and ships with an Arduino-compatible serial bootloader; you can also use an AVR in-system programmer (ISP) for access to the entire chip. We recommend our USB AVR Programmer v2, which supports both programming interfaces and can be configured to run at either 3.3 V or 5 V.

Last but not least, we are continuing our plan of offering new products at the highest quantity price break at single unit quantities as an introductory celebration. That means that for the first 100 customers, you can get an A-Star 328PB Micro for just $3.87! (Must use coupon code AS328PBINTRO; click to add the coupon code to your cart.)

While we assemble (and design and document and ship and support) the boards here in Las Vegas, we still get the bare PC boards from China, where they are currently on holiday celebrating Chinese New Year. That is constraining how many units we can make at the moment, so we are limiting shipments to 5 units per customer. However, the introductory coupon has no quantity limit, and you can order more than five at that price if you would like. Backordered units are likely to ship within a few weeks.


I know this is not the right place for this, but I need help with this board... I ordered a couple of them (and two of the 2.1 prog's) when you sent out that email, but I am STILL not able to compile for them in any of my Arduino programming environments (Arduino, MS VS Code, Visual Studio 2017 w/ Visual Micro (paid) plugin).

It looks like the compiler is not liking spaces in my PC (Win 10/HP I5/8GB laptop) user name, but as I would have to completely re-install the OS to change it, I am unwilling to do so.

The error I get is this:

avr-g++: error: **LAST PART OF MY TWO-WORD-WITH-A-SPACE USERNAME HERE**\AppData\Local\Arduino15\packages\pololu-a-star\hardware\avr\4.0.1/variants/a-star328pb/io_328pb.h: No such file or directory

I have verified the path and file exists, and that is the correct path, minus the obligatory C:\users\**FIRST PART OF MY USERNAME**.

Can you point me to the file I need to edit to correct this? I "assume" we need a \% or something in there to support it. While I'm pretty comfortable and not new to embedded programming, I am far from conversant with the intricacies of the Arduino programming environment.

Thank you,
Hi, Brad.

I'm sorry you've been having trouble working with your A-Star 328PBs. You are right about the cause of the error, and we've published a new version of our A-Star boards package to fix it. Please try updating to the latest version (4.0.2) through the Arduino IDE's Boards Manager and see if it works for you.

If you continue to have trouble, our forum is a better place for troubleshooting, so please post there.

Thank you Kevin. After updating I was able to upload via ICSP, but not Serial. I will go look at the forum.

I am a proud owner of a A-Star 328PB board together with your USB AVR programmer v2.1. I managed to get these things successfully running on my Linux box (Ubuntu 18.04) with my toolchain consisting of geany, avr-gcc, avrdude etc. on a late afternoon yesterday. Yes, blinking yellow LED was the first evidence of successful operation.

The very minor thing I would like note today is the fact, that the 6-pin connection between these boards should have more clarification on your side, especially how to plug the programming cable to the A-Star side. I simply noticed that the ground connection was the guiding star, but others may have a higher risk than me to plug it in the wrong direction.

So could you please include an additional picture where the A-Star is described in more detail showing clearly how the cable and plug should be oriented to be correctly inserted on the A-Star board? BTW I appreciate your entire textual and visual description with great satisfaction on your site. I believe it is of great help for beginners and for more advanced experimenters too.
The "Connecting to the serial interface" section of the A-Star 328PB User's Guide has instructions specifically for using our USB AVR Programmer v2.1, including a picture of the connected boards. If you requesting something beyond what we already have there, can you elaborate?

Hi Brandon,

thank you for your swift response. The picture you mentioned is not covering my case. If you can insert the flat ISP cable from the programmer to the board in such picture clearly indicating the no.1 wire in red would be helpful and supportive to establish unambiguousness with respect to correct plug orientation.



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