2023-06-21 08:22:56 -05:00
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jmp r0, start
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start:
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jmp r0, init_serial_port
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-- Uses r20 to set the port
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init_serial_port:
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add r20, r30, r10
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2023-06-26 05:18:14 -05:00
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li r20, 00
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-- outb(PORT + 1, 0x00); // Disable all interrupts
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-- outb(PORT + 3, 0x80); // Enable DLAB (set baud rate divisor)
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-- outb(PORT + 0, 0x03); // Set divisor to 3 (lo byte) 38400 baud
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-- outb(PORT + 1, 0x00); // (hi byte)
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-- outb(PORT + 3, 0x03); // 8 bits, no parity, one stop bit
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-- outb(PORT + 2, 0xC7); // Enable FIFO, clear them, with 14-byte threshold
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-- outb(PORT + 4, 0x0B); // IRQs enabled, RTS/DSR set
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-- outb(PORT + 4, 0x1E); // Set in loopback mode, test the serial chip
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-- outb(PORT + 0, 0xAE); // Test serial chip (send byte 0xAE and check if serial returns same byte)
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