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| author | Jan Tuomi <jan@jantuomi.fi> | 2024-04-13 16:23:36 +0300 |
|---|---|---|
| committer | Jan Tuomi <jan@jantuomi.fi> | 2024-04-13 16:23:36 +0300 |
| commit | 374feaf304df4fababf82af72776e8e98df00be8 (patch) | |
| tree | e9eb78b26d521b88826abccc01c3e2e7e7aa0b1f /atk16_asm/builtin_asm | |
| parent | 3f9f7eefb9d0836ec53a08e311219f7f497517c7 (diff) | |
WIP peripherals
Diffstat (limited to 'atk16_asm/builtin_asm')
| -rw-r--r-- | atk16_asm/builtin_asm/std_mem.atk16 | 19 |
1 files changed, 19 insertions, 0 deletions
diff --git a/atk16_asm/builtin_asm/std_mem.atk16 b/atk16_asm/builtin_asm/std_mem.atk16 new file mode 100644 index 0000000..4c6a455 --- /dev/null +++ b/atk16_asm/builtin_asm/std_mem.atk16 @@ -0,0 +1,19 @@ +@label memset + ; sets a specified number of words in memory to a specified value + ; parameters: RA = offset (offset in memory to start at) + ; RB = n (number of words to set) + ; RC = val (value to set the words to) + ; returns: void + stack_stash RD RE + ldi 0 RD ; RD := i (counter), initially 0 +@label memset_loop + subi RB RD RE ; RE := n – i (unused value) + bri zero memset_done ; exit the loop + + add RA RD RE ; RE := RA + i (address of the word to set) + str RC RE ; set the word at address RE to value in RC + + inc RD ; i := i + 1 +@label memset_done + stack_restore RD RE + return |