ref: df04ea8d6c2e1e75307a77f2b086a836f480ab72
dir: /sys/src/boot/pc/uart.s/
#include "x16.h" TEXT uartinit(SB), $0 MOVL c+8(SP), AX MOVB $0x00, AH JMP _uartbios TEXT uartputc(SB), $0 MOVL c+8(SP), AX MOVB $0x01, AH JMP _uartbios TEXT uartgetc(SB), $0 MOVL p+4(SP), DX CALL rmode16(SB) STI MOVB $0x03, AH BIOSCALL(0x14) CALL16(pmode32(SB)) ANDL $0x8100, AX MOVL $0x0100, BX CMPL BX, AX JE _uartread XORL AX, AX RET _uartread: MOVB $0x02, AH _uartbios: MOVL p+4(SP), DX CALL rmode16(SB) STI BIOSCALL(0x14) CALL16(pmode32(SB)) ANDL $0xFF, AX RET