Refactoring PC components

okean240/pic/pic8259.go

@@ -0,0 +1,54 @@
+package pic
+
+/*
+    Programmable Interrupt Controller
+	i8058, MSM82C59, КР580ВН59
+
+	By Romych, 2025.03.05
+*/
+
+import log "github.com/sirupsen/logrus"
+
+type I8259 struct {
+	irr byte
+}
+
+type I8259Interface interface {
+	SetIRQ(irq byte)
+	IRR() byte
+}
+
+func (c *I8259) IRR() byte {
+	irr := c.irr
+	// Reset the highest IR bit
+	if irr&0x80 != 0 {
+		c.irr &= 0x7F
+	} else if irr&0x40 != 0 {
+		c.irr &= 0x3F
+	} else if irr&0x20 != 0 {
+		c.irr &= 0x1F
+	} else if irr&0x08 != 0 {
+		c.irr &= 0x07
+	} else if irr&0x04 != 0 {
+		c.irr &= 0x03
+	} else if irr&0x02 != 0 {
+		c.irr &= 0x1
+	} else {
+		c.irr = 0
+	}
+	return irr
+}
+
+func (c *I8259) SetIRQ(irq byte) {
+	if irq < 8 {
+		c.irr |= 1 << irq
+	} else {
+		log.Warnf("SetIRQ out of range [0..7]: %d", irq)
+	}
+}
+
+func NewI8259() *I8259 {
+	return &I8259{
+		irr: 0,
+	}
+}