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2020-12-08- Fixed yet another bug with the ortho extension.mrb0nk500
2020-12-08- Implemented support for the Orthogonal extension intomrb0nk500
both the assembler, and the emulator. I finally figured out how I could get support for the Ortho extension implemented into the old assembler. The only reason for doing this, is to buy me some while I start work on the new assembler, and to help me get an idea for how to do the same in the new assembler.
2020-11-20- Implemented support for Sux's base extension.mrb0nk500
This is the biggest milestone I've reached for this project, since the base extension changes alot about what Sux can do by default, and now makes it a viable instruction set for modern day use, when compared with other instruction sets.
2020-11-20- Cleaned up a bit of the code.mrb0nk500
- Made the debug print for the CPU flags more readable. - Started work on implementing line number support into SuBAsm.
2020-10-06- Made the stack pointer 64 bit, rather than 16 bit.mrb0nk500
This is to allow for making the stack bigger for anything that needs to change the size of it. - Made the SuB Suite set the stack pointer to the end of the usable RAM, and allow for changing the stack size. In this case, the size of the stack is currently set to 192K, with the end of the heap being just below the stack.
2020-10-04- Added support for reading, and writing outside themrb0nk500
emulator's memory. All reads outside of the emulator's memory give back $/0xFF bytes, while all writes outside of the emulator's memory are ignored. - Implemented malloc(), and free() in the SuB Suite. In order to do this, I had to add support for a heap, which I did by reserving the first 3 banks of the address space (the first 192K), and by adding a routine that finds the end of the RAM. In this case, I set the starting address for the routine at bank 3 (bank 4 with one indexing), but, the routine's starting address isn't hardcoded, and thus, any starting address can be passed as an argument. The routine uses the fact that we can now read/write outside the emulator's memory, and also uses the fact that writing outside the emulator's memory will be ignored, and that reading outside the emulator's memory will always read $/0xFF bytes, and uses that to signal that it's reached the end of the RAM. - Added a test program for getting the size of RAM starting at address $/0x20000.
2020-09-24- Fixed some more bugs with struct, and union handling.mrb0nk500
2020-08-31- Optimized the memory read/write functions a bit more.mrb0nk500
- Added a memcopy() function, for later on.
2020-08-30- Did some more work on SuBAsm's lexer.mrb0nk500
- Optimized the memory read, and write functions. - Made the emulator faster, and cleaner in general.
2020-08-17- Fixed some bugs in the emulator's assembler.mrb0nk500
- Simplified the effective address functions. - Made SuBEditor a bit faster. - JSR, and RTS now support using the RS prefix, which is used to specify the return address size, with an RS prefix of 0 being a return address size of 64 bits, rather than 8 bits.
2020-08-13Refactored get_addr(), and all of the effectivemrb0nk500
address handling. It's now all done using several functions for each addressing mode, with the result being the effective address. I did this to make the codebase cleaner, and more readable.
2020-08-12- Refactored the escape sequence parsing, and handling.mrb0nk500
It now uses a struct to store the escape sequence. Before it handles the escape sequence, it parses it, which includes things like getting any arguments that are supplied, and getting the mode type. - Moved the code that handles control codes to a separate function. The reason for doing this was because I wanted to make the escape sequence handling faster, but also make the code more readable at the same time. I got the idea to do this from st, a terminal emulator created by the suckless.org project.
2020-08-08- Refactored the opcode table, in order to make themrb0nk500
instruction formatting simpler. - Refactored the instruction table of the emulator's assembler, it now has two parts, the addressing mode bits, and the base value. The base value is what's used to generate the actual opcode, with the addressing mode bits telling the assembler what addressing modes this instruction supports. The reason for doing this was to use less space. For comparison, the previous version used 870 bytes for the instruction table, while the new version uses only 222 bytes. The new version is nearly 4 times smaller than the pervious version. - The B register based ALU instructions now use their own addressing mode, and are specified by using 'b' as the operand for those instructions. For example, to add the Accumulator with the B register, you now use "ADC B" instead of "AAB".
2020-08-08Did a ton of stuff.mrb0nk500
- Changed the file structure of the SuB Suite, so that all variable declarations, symbols, and constants are in a single file. - Moved the C library functionss into a separate file, and made them use stack frames. - Added support for using the emulator's assembler for realtime debugging, to enter it, get in to stepping mode by pressing Ctrl+s, press any other key, then press F1, The reason for having to press some other key before pressing F1 is because it only allows entering the assembler when the keyboard is not ready. - Added the ".res" directive to the emulator's assembler, the ".res" directive tells the assembler to reserve however many bytes specified by the operand. - Fixed some bugs in the emulator's assembler.
2020-07-06- Implemented a new opcode table.mrb0nk500
- Added a new preifx called the OF prefix, which adds the contents of a specific register to the current operand. - Added a table generator, which parses opcode table csv files.
2020-06-22Did some more stuff.mrb0nk500
- Fixed some bugs in the emulator's assembler. - Worked on SuBAsm's lexer some more. - Created a new directory for the SuB suite, and moved all of the SuB suite's files in there.
2020-06-13Make the registers single 64 bit uints, and convertmrb0nk500
all the value getting, and setting into macros. This is to make the codebase cleaner.
2020-05-29Make JSL, JSR absolute, and remove RTL.mrb0nk500
The reason for doing this was because JSL, and RTL are redundent, as they both do the same thing as JSR, and RTS.
2020-05-28Refactored the assembler, yet again, and implementedmrb0nk500
support for comma separated values. The assembler now uses a linked list of tokenized lines, each containing a linked list of tokens for that line. I also moved all of the large tables into the higher parts of memory, in order to free up the lower part of memory for the user. Comma sepparated values only work with directives, and only with the byte", word, dword, and qword directives. I also added support for getting the upper, and lower halves of an address. The tokens for both of those are '<', and '>' respectively.
2020-05-03Put the instruction, and I/O routines into separatemrb0nk500
functions. I did this to make it more readable, while still making it fast, due to inlining it.