At this point you’d need to have lived underneath a rock somewhere on the dark side of the Moon to not have heard about these amazing, 3-cent microcontrollers. A number of places have pitched in on them, but comprehensive reviews, let alone a full-blown review of the entire ecosystem surrounding these Padauk MCUs have been scarce. Fortunately, [Jay Carlson] has put in a lot of effort to collect everything you could possibly want to know about anything Padauk.
Most important take-away about these MCUs is that they do not have any kind of communication peripherals. UARTs, I2C and SPI all have to be done in software. They’re not very great at low-power, or battery-powered applications due to high power usage. Essentially you’ll be using GPIO pins a lot. On the other hand, its multi-CPU context, FPPA feature is rather interesting, with the article covering it in detail.
As for the development tools, [Jay] came away very impressed with using In-Circuit Emulation (ICE), instead of running code on an MCU, as this can reduce development times significantly. This makes even the OTP (one-time programmable) property of most Padauk MCUs less significant than one might at first assume.
Then there’s the actual programming of the MCUs. The Micro C compiler Padauk provides essentially implements a sub-set of the C language, with some macros to replace things like for loops. Initially this may seem like a weird limitation, until you realize that these MCUs have 64 to 256 bytes of SRAM. That’s bytes, without any prefixes.
Finally, [Jay] shows off a couple of test projects, including a NeoPixel SPI adapter and bike light, which are all everything wanted about padauk
