CERES-16

a shitty fantasy console written in rust using a proprietary MIPS based asm instruction set. a lot of inspiration from PICO-8. ceres is structured of these crates:

• ceres-sys: the core system structure of ceres-16
• ceres-asm: the assembler for ceres-16

Graphics

ceres uses a 256x144 screen with a separate video buffer from the standard memory. colors are 16-bit structured like 0b0000_rrrr_gggg_bbbb where the first four bits are ignored. the video buffer is structured row major where each u16 is an individual pixel

Register layout and info

all registers are unsigned 16 bit

Register number	Register name	Register usage
0	z0	always contains zero
1	pc	program counter
2	sp	stack pointer
3	ra	return address
4-6	a0-a2	argument registers
7	v0	return register
8	v1	return register 2
9-15	t0-t6	temporary registers

Memory map and info

god oh fuck what am i even doing

instructions

load - ld:signifier $dest immediate/address

opcode	signifier	destination	padding	immediate/address
00001	000	0000	0000	0000000000000000

store - st:signifier address $source

opcode	signifier	source	padding	address
00100	000	0000	0000	0000000000000000

add - add $src1 $src2 $dest

opcode	padding	source1	source2	dest
00010	000000000000000	0000	0000	0000

sub - sub $source1 $source2 $dest

opcode	padding	source1	source2	dest
00011	000000000000000	0000	0000	0000