Sol-1 is a homebrew CPU and Minicomputer built from 74HC logic.
Features
Hardware
– User and Kernel privilege modes, with up to 256 processes running in parallel.
– Paged virtual memory, such that each process can have a total of 64KB RAM for itself.
– Two serial ports (16550), a real time clock(M48T02), 2 parallel ports(8255), a programmable timer(8253), an IDE hard-drive interface(2.5 Inch HDD), and a soundboard(AY-3-8910).
– 8 prioritized external interrupts
– DMA channel
– The sequencer is microcoded, with 15 ROMS operating horizontally
– 8/16-Bit MUL and DIV instructions
– Fast indexed string instructions in the spirit of x86’s REP MOVSB, CMPSB, LODSB, STOSB, etc
Register Table
General Purpose Registers
| 16bit | 8bit | Description | ----- | ----- | ----------- | A | AH/AL | Accumulator | B | BH/BL | Base Register (Secondary Counter Register) | C | CH/CL | Counter Register (Primary Counter) | D | DH/DL | Data Register / Data Pointer | G | GH/GL | General Register (For scratch)
Special Purpose Registers
| 16bit | 8bit | Description | ------ | --------- | ----------- | PC | | Program Counter | SP | | Stack Pointer | SSP | | Supervisor Stack Pointer | BP | | Base Pointer (Used to manage stack frames) | SI | | Source Index (Source address for string operations) | DI | | Destination Index (Destination address for string operations) | PTB | | Page Table Base | Status | | CPU Status | Flags | | Arithmetic and Logic flags register | TDR | TDRH/TDRL | Temporary Data Register (Internal CPU scratch register)
Software
* Unix-like operating system
* Assembler
* Full C compiler
* SystemVerilog model
* Emulator
* I plan to port the original Colossal Cave adventure, as well as many other text-adventure games in the near future.
