X-Git-Url: http://git.mutantstargoat.com/user/nuclear/?p=dosdemo;a=blobdiff_plain;f=libs%2Foldmik%2Fsrc%2Fmirq.c;fp=libs%2Foldmik%2Fsrc%2Fmirq.c;h=96cbcf71b10377b45ebf1e310036725ebe417e31;hp=0000000000000000000000000000000000000000;hb=77db1ca18d5446dcda9e524261399b63c2cd1813;hpb=a714b8c4811627d874934b0a0387b8cb27fc5921

diff --git a/libs/oldmik/src/mirq.c b/libs/oldmik/src/mirq.c
new file mode 100644
index 0000000..96cbcf7
--- /dev/null
+++ b/libs/oldmik/src/mirq.c
@@ -0,0 +1,99 @@
+/*
+
+Name:
+MDMA.C
+
+Description:
+Some general purpose IRQ routines
+
+Portability:
+
+MSDOS:	BC(y)	Watcom(y)	DJGPP(y)
+Win95:	n
+Os2:	n
+Linux:	n
+
+(y) - yes
+(n) - no (not possible or not useful)
+(?) - may be possible, but not tested
+
+*/
+#include <dos.h>
+#include <conio.h>
+#include "mirq.h"
+
+#define OCR1	0x20			/* 8259-1 Operation control register */
+#define IMR1	0x21			/* 8259-1 Mask register */
+
+#define OCR2	0xA0			/* 8259-2 Operation control register */
+#define IMR2	0xA1			/* 8259-2 Mask register */
+
+
+BOOL MIrq_IsEnabled(UBYTE irqno)
+/*
+	Returns true if the specified hardware irq is enabled.
+*/
+{
+	UBYTE imr=(irqno>7) ? IMR2 : IMR1;		/* interrupt mask register */
+	UBYTE msk=1<<(irqno&7);					/* interrupt mask */
+	return((inportb(imr) & msk) == 0);
+}
+
+
+BOOL MIrq_OnOff(UBYTE irqno,UBYTE onoff)
+/*
+	Use to enable or disable the specified irq.
+*/
+{
+	UBYTE imr=(irqno>7) ? IMR2 : IMR1;		/* interrupt mask register */
+	UBYTE ocr=(irqno>7) ? OCR2 : OCR1;		/* ocr */
+	UBYTE msk=1<<(irqno&7);					/* interrupt mask */
+	UBYTE eoi=0x60|(irqno&7);				/* specific end-of-interrupt */
+	BOOL oldstate;
+
+	/* save current setting of this irq */
+	oldstate=((inportb(imr) & msk) == 0);
+
+	if(onoff){
+		outportb(imr,inportb(imr) & ~msk);
+		outportb(ocr,eoi);
+		if(irqno>7) MIrq_OnOff(2,1);
+	}
+	else{
+		outportb(imr,inportb(imr) | msk);
+	}
+
+	return oldstate;
+}
+
+
+void MIrq_EOI(UBYTE irqno)
+/*
+	Clears the specified interrupt request at the interrupt controller.
+*/
+{
+        outportb(0x20,0x20);
+        if(irqno>7) outportb(0xa0,0x20);
+}
+
+
+PVI MIrq_SetHandler(UBYTE irqno,PVI handler)
+{
+#ifdef __DJGPP__
+	_go32_dpmi_seginfo seginfo;
+#endif
+	PVI oldvect;
+	int vecno=(irqno>7) ? irqno+0x68 : irqno+0x8;
+#ifdef __DJGPP__
+	_go32_dpmi_get_protected_mode_interrupt_vector(vecno, &seginfo);
+	oldvect = seginfo.pm_offset;
+	seginfo.pm_offset = handler;
+	seginfo.pm_selector = _go32_my_cs();
+	_go32_dpmi_allocate_iret_wrapper(&seginfo);
+	_go32_dpmi_set_protected_mode_interrupt_vector(vecno, &seginfo);
+#else
+	oldvect=_dos_getvect(vecno);
+	_dos_setvect(vecno,handler);
+#endif
+	return oldvect;
+}