Baochip
@baochip
Baochip makes open-source hardware.
A version of the BIO core has been taped out and will be on the @wafer.space run 2! Thanks to Deepak Sharda (twitter: x.com/deeempak / website: lut4.com) for doing the heavy lifting of porting a version of the Baochip BIO core to this process! Full design available at github.com/dpks2003/bio...
The Baochip-1x is IR-inspectable. But, how does one read chips, and what does it even mean? Here's a blog post put out by @bunnie.org that helps make sense of the Baochip-1x SRAM macros, and its implications for trusted boot: www.bunniestudios.com/blog/2026/on...
One of my favorite features about the Baochip-1x is the BIO. I've just put out a post explaining the origin of the BIO, including a comparative study against the PIO and some examples of how to use it. www.crowdsupply.com/baochip/daba...
Production tester for the dabao is ready! 100% of boards run through a test where every I/O is toggled, both buttons are pressed, serial ports tickled, and an initial OS image is loaded. Voltages and currents are also checked. The test checks for errors in soldering, and/or faulty components.
Here's what a socket looks like for chip scale packages. Each one is custom made for a given chip package. A couple samples of the 0.4mm pitch Baochip CSP devices are laid out on the lower rim of the socket for size reference.
Behold the graveyard of Baochips! Security testing is hard, after the chips are locked the only recourse is to desolder and replace them when a test goes wrong or an attack sensor is tripped. On the upside, I'm getting really good at reworking CSPs.
Woo hoo! just in time: tape & reel packaged Dabao for #39c3. They will be at the #fail0verflow assembly with @bunnie.org . Also come see our talk on Day 2 23:00 in Room 1: "Xous: A Pure-Rust Rethink of the Embedded Operating System", where bunnie & xobs will co-present on Xous running on Baochip!
The basic dev board is in! Meet the "Dabao", a simple breakout board for the Baochip-1x. If you're interested in one and will be at #39C3, come find @bunnie.org at the fail0verflow assembly. He'll have a limited number of Alpha-1 release boards to give away! Source at github.com/baochip/dabao
The first cut of the code missed a branch delay slot, and so the two paths were different by three cycles. Open source means you can simulate code running on your chip, and be sure you got it right!
It's nice to be able to simulate your constant-time code and prove to yourself that you got it right. Pictured is a simulation of AES chaffing, where fake and real data are computed in a random order. The timing of fake->real and real->fake has to be identical in order to mask power side channels.
Backside IR image of the chip! The Baochip-1x is packaged specifically to enable you to verify that you've got the correct chip, and not a fake or a substitute part (see bunnie.org/iris for how). The final chip will have part numbering that overlaps the memory array on the lower third of the chip.
CHIIIIIIPS!!! 12" wafer of CSP bumped chips, hot off the line (solder balls are face-up in this photo, with a couple die already removed for testing).
A killer app for SoC source code is debugging your code with RTL simulation. Simulation gets you cycle-accurate views into what's happening throughout the system - the program counter, registers, state machines. Learn more on how to simulate the Baochip-1x here: baochip.github.io/baochip-1x/c...
