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just learned you can index with ecx, updated assembly accordingly

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This commit is contained in:
Benji Dial 2019-12-26 16:24:32 -05:00
parent e0e08a12d4
commit dc6b746faa
1 changed files with 11 additions and 18 deletions
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29
src/kernel/serial.asm
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@ -22,18 +22,14 @@ send_byte:;void send_byte(uint8_t value, uint8_t port)
push ebp push ebp
mov ebp, esp mov ebp, esp
mov cl, byte [ebp + 8] ;value xor ecx, ecx
xor edx, edx mov cl, byte [ebp + 12];port
mov dl, byte [ebp + 12];port
test dl, 0xfc test cl, 0xfc
jnz .leave jnz .leave
xchg ebx, edx shl cl, 1
shl bl, 1 mov dx, word [ecx + com_ports]
mov ax, word [ebx + com_ports]
mov ebx, edx
mov dx, ax
or dx, 5 or dx, 5
@ -44,7 +40,7 @@ send_byte:;void send_byte(uint8_t value, uint8_t port)
and dx, 0xfff8 and dx, 0xfff8
mov al, cl mov al, byte [ebp + 8];value
out dx, al out dx, al
.leave: .leave:
@ -57,17 +53,14 @@ read_byte:;uint8_t read_byte(uint8_t port)
xor eax, eax xor eax, eax
xor edx, edx xor ecx, ecx
mov dl, byte [ebp + 8];port mov cl, byte [ebp + 8];port
test dl, 0xfc test cl, 0xfc
jnz .leave jnz .leave
xchg ebx, edx shl cl, 1
shl bl, 1 mov dx, word [ecx + com_ports]
mov cx, word [ebx + com_ports]
mov ebx, edx
mov dx, cx
or dx, 5 or dx, 5