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Thanks for answering my questions. Your project is really really interesting. Two more questions if you find some spare time: 3. Why does it use tty for inter

Thanks for answering my questions. Your project is really really interesting. Two more questions if you find some spare time: 3. Why does it use tty for interrupts instead of directly calling int 10? 4. How does this even print to the screen or use a tty in the first place? Is it just something inherent in bios api?

shikaan 1y ago
Hey, thanks for your interest in this project! 3. The tty interrupt advances the cursor along with printing. So, once again, I do it to save on some instructions. In the first iterations I wanted to retain more control (by printing and moving as separate operations) so that I could reuse this across the board, but eventually I ran out of space. 4. I am relying heavily on BIOS interrupts, which are criminally underdocumented. The most reliable source is Ralph Brown's documentation[1] which is very far from what I was expecting to be authoritative documentation. Turns out this collection is really good and basically _the_ source of truth for BIOS interrupts. To answer your question, yes, this is basically calling the BIOS API. [1]: https://wiki.osdev.org/Ralf_Brown's_Interrupt_List https://wiki.osdev.org/Ralf_Brown's_Interrupt_List
- rerdavies 1y ago
  THIS is the bible for BIOS APIs" https://bitsavers.trailing-edge.com/pdf/ibm/pc/ps2/PS2_and_PC_BIOS_Interface_Technical_Reference_Apr87.pdf https://bitsavers.trailing-edge.com/pdf/ibm/pc/ps2/PS2_and_P... Complete with reference assembler source code.
  - shikaan 1y ago
    Oh boy, this is amazing! Thanks for the reference