Renesas Unveils ARM Cortex-M85 Based MCU with I3C Ternary Mode Support

Earlier this week Renesas publicly revealed their new RA8 series of microcontrollers, which is notably the industry’s first implementation of the ARM Cortex-M85 core. (There’s way more nuance to it, but at the highest level, the Cortex-M33 can be thought of as the next generation of M4 devices, the M85 can be thought of as the next-gen of M7 devices.) While remarkable on it’s own, frequent readers will know that we are really only here to discuss one thing: I3C.

It’s of course no surprise that the RA8M1-series features I3C support, as the RA4E2 and RA6E2 launched earlier this year had I3C peripherals. However, here’s the real surprise that’s buried deep in the technical documentation for this device. While Renesas’s previous I3C-capable devices were limited to SDR mode of operation, the RA8M1 introduces support for HDR mode. And not just HDR-DDR mode, but for the whole set. HDR-DDR, HDR-TSL, and HDR-TSP. That’s right - this is the first MCU publicly available with ternary mode support. You can find this mentioned on page 1455 of the RA8M1 User Manual.

Development kits are already conveniently available for purchase from DigiKey and Mouser, but buyer beware, there appears to be just one I3C example project included in their Example Application bundle, so it’s definitely going to take some time and effort to get an I3C Ternary mode demo running on your desk.

Already working with I3C? Check out our I3C Basic Protocol Analyzer Plugin for Saleae Logic…