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-rw-r--r--src/Boot/Windows/BootConsoleIo.cpp23
1 files changed, 22 insertions, 1 deletions
diff --git a/src/Boot/Windows/BootConsoleIo.cpp b/src/Boot/Windows/BootConsoleIo.cpp
index b03098f..9148f5c 100644
--- a/src/Boot/Windows/BootConsoleIo.cpp
+++ b/src/Boot/Windows/BootConsoleIo.cpp
@@ -238,11 +238,32 @@ byte GetKeyboardChar ()
return GetKeyboardChar (nullptr);
}
+/*
+inline void Sleep ()
+{
+ __asm
+ {
+ mov al, 0
+ mov ah, 0x86
+ // Sleep for 250 milliseconds = 250 000 microseconds = 0x0003D090
+ mov cx, 0x0003
+ mov dx, 0xD090
+ int 0x15
+ }
+}
+*/
byte GetKeyboardChar (byte *scanCode)
{
// Work around potential BIOS bugs (Windows boot manager polls the keystroke buffer)
- while (!IsKeyboardCharAvailable());
+ while (!IsKeyboardCharAvailable())
+ {
+ // reduce CPU usage by halting CPU until the next external interrupt is fired
+ __asm
+ {
+ hlt
+ }
+ }
byte asciiCode;
byte scan;