fb3c7e04c4
This includes both separate .md files, and documentation that was on the head of the .S source files. Retest everything as this was done, and fix a few easy things.
36 lines
714 B
ArmAsm
36 lines
714 B
ArmAsm
#include "common.h"
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BEGIN
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/* Chanel 2, square wave, load TODO?, binary */
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mov $0xb6, %al
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out %al, $0x43
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/* Set frequency of Channel 2. */
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.equ div, 1193181 / 1000
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mov div, %ax
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out %al, $0x42
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mov %ah, %al
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out %al, $0x42
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/* Dummy read of System Control Port B. TODO why? */
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in $0x61, %al
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/* Enable timer 2 output to speaker.
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* THIS is where the sound begins.
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*/
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mov $0x03, %al
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out %al, $0x61
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/* Loop forever to keep hearing it. */
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loop:
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nop
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jmp loop
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/* This is how a sound can be stopped.
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* This code never reached in this example.
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* unless you hack it up.
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*/
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in $0x61, %al
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mov $0x00, %al
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out %al, $0x61
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