diff options
Diffstat (limited to 'src/serial.c')
| -rw-r--r-- | src/serial.c | 51 |
1 files changed, 42 insertions, 9 deletions
diff --git a/src/serial.c b/src/serial.c index 8ca7e367..026c399d 100644 --- a/src/serial.c +++ b/src/serial.c @@ -54,6 +54,7 @@ getComAddr(struct bregs *regs) return addr; } +// SERIAL - INITIALIZE PORT static void handle_1400(struct bregs *regs) { @@ -75,14 +76,10 @@ handle_1400(struct bregs *regs) set_success(regs); } -static void -handle_1401(struct bregs *regs) +static int +write_serial(u16 addr, u16 timeout, char c) { - u16 addr = getComAddr(regs); - if (!addr) - return; u16 timer = GET_BDA(timer_counter); - u16 timeout = GET_BDA(com_timeout[regs->dx]); while (((inb(addr+5) & 0x60) != 0x60) && (timeout)) { u16 val16 = GET_BDA(timer_counter); if (val16 != timer) { @@ -90,14 +87,29 @@ handle_1401(struct bregs *regs) timeout--; } } - if (timeout) - outb(regs->al, addr); - regs->ah = inb(addr+5); if (!timeout) + // Ran out of time. + return -1; + outb(c, addr); + return 0; +} + +// SERIAL - WRITE CHARACTER TO PORT +static void +handle_1401(struct bregs *regs) +{ + u16 addr = getComAddr(regs); + if (!addr) + return; + u16 timeout = GET_BDA(com_timeout[regs->dx]); + int ret = write_serial(addr, timeout, regs->al); + regs->ah = inb(addr+5); + if (ret) regs->ah |= 0x80; set_success(regs); } +// SERIAL - READ CHARACTER FROM PORT static void handle_1402(struct bregs *regs) { @@ -122,6 +134,7 @@ handle_1402(struct bregs *regs) set_success(regs); } +// SERIAL - GET PORT STATUS static void handle_1403(struct bregs *regs) { @@ -159,6 +172,26 @@ handle_14(struct bregs *regs) /**************************************************************** + * Serial debugging + ****************************************************************/ + +#define BX_DEBUG_PORT 0x03f8 + +void +debug_serial_setup() +{ + /* setup for serial logging: 8N1 */ + outb(0x03, BX_DEBUG_PORT+3); +} + +void +debug_serial(char c) +{ + write_serial(BX_DEBUG_PORT, 0x0a, c); +} + + +/**************************************************************** * LPT ports ****************************************************************/ |