Wow! Congratz Kenneth!! =) -- CeDeROM, SQ7MHZ, http://www.tomek.cedro.info
-- CeDeROM, SQ7MHZ, http://www.tomek.cedro.info On Mon, Oct 26, 2026 at 5:37 PM Alan C. Assis <[email protected]> wrote: > > WOW!!! > > Amazing!!! Kudos Ken!!! > > And a nice demo image! > > BR, > > Alan > > On Mon, Oct 26, 2026 at 1:12 PM Kenneth Pettit <[email protected]> wrote: >> >> Hi all, >> >> Been a while since I have posted. I have been getting into using NuttX >> again (at work) on a RISC-V processor I am embedding in one of our ASICs. >> But for my personal home projects, I have been using it a bit also. >> >> In 2024, I created a custom-ISA 8-bit CPU called LISA (Little ISA). And I >> wrapped a microcontroller around it and taped it out on TinyTapeout TT06 >> (and again on TT07). >> >> The goal of LISA was "How small of a CPU can I make that still runs C". >> Seems it was 94 flops, and I wrote my own custom assembler, C compiler, >> linker and debugger. Though the C compiler had more bugs than working >> features. And LISA only supported 32K CODE + 32K DATA. >> >> Over the past couple of months I have been working on the new version of >> LISA ... 8MB code + 8MB data space, a real SDCC toolchain, and it only grew >> to 150 flops for the actual CPU core. Then I added more peripherals, >> interrupts, etc. And now I have it (on FPGA ... will tape out in December) >> so it runs NuttX 13.1.0!! >> >> This is a screenshot of it running in on Arty A7 FPGA with I2C interface to >> an OLED display running full NuttX. Amazing where this OS can run! >> >> >> >> Ken
