17 lines
380 B
ArmAsm
17 lines
380 B
ArmAsm
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// Copyright 2014 Normmatt
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// Licensed under GPLv2 or any later version
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// Refer to the license.txt file included.
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.arm
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.global ioDelay
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.type ioDelay STT_FUNC
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@ioDelay ( u32 us )
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ioDelay:
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ldr r1, =0x18000000 @ VRAM
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1:
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@ Loop doing uncached reads from VRAM to make loop timing more reliable
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ldr r2, [r1]
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subs r0, #1
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bgt 1b
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bx lr
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