I’ve spent a bit of time over the past couple of months re-implementing the microcode assembler from scratch. The original microcode assembler was thrown together to save me from typing 64 ones and zeroes for every word of microcode (which […]
I implemented the microcode for the 16 bit, 8 bit low, and 8 bit high variants of AND, OR, and XOR this evening, which went smoothly (if a bit tediously). At this point 47 instructions are implemented in microcode, and […]
The new LLVM-based assembler is fully working, and 100% of the regression tests have been moved over to it as of this afternoon. It took close to 9 months to get done, but it’s all working now and gives us […]
I’ve spent the last few evenings tweaking the LLVM backend’s MC code to fix a lot of minor issues, and it’s to the point where it can generate normal output from ECLair assembly input now! It understands that different instructions […]
Worked on the LLVM backend a bunch more this evening, and it successfully assembled something for the first time! Halt is just 0xfe but the backend only understands 16-bit instructions at the moment, so it assembled as noop, halt, but […]
I haven’t made any posts here in ages, but that doesn’t mean that work hasn’t been happening behind the scenes! I looked at what my options were last fall when it came to assemblers, and it looked like I had […]
Started working on the implementation of jmpe/jmpne, got frustrated that the temporary assembler still doesn’t support two-byte instructions. Fixed this, it now looks at the opcode and figures out which instruction will require a second register-selector byte and handles this […]
While thinking about the toolchain I realized I hadn’t ever finished implementing branch instructions. Today I added a microcode bit to negate branching (for the ‘if not’ jump instructions), and implemented the jmpnz and jmpno instructions. Also updated the test […]
As I started looking at adding ECLair’s instructions to the LLVM port, I realized that a lot of them aren’t organized in a reasonable way. For example, add16 with the source/dest register A has an entirely different pattern of bits […]
I’ve spent a bunch of my spare time over the past few months figuring out a toolchain for ECLair. I’m using LLVM so far, and have been working on learning how to port it to a new target platform and […]