mirror of
https://github.com/romychs/Ocean-240.2-Emulator.git
synced 2026-04-21 11:03:21 +03:00
66 lines
939 B
Go
66 lines
939 B
Go
package pic
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/*
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Programmable Interrupt Controller
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i8058, MSM82C59, КР580ВН59
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By Romych, 2025.03.05
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*/
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import log "github.com/sirupsen/logrus"
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type I8259 struct {
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irr byte
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csw byte
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}
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type I8259Interface interface {
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SetIRQ(irq byte)
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IRR() byte
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CSW() byte
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SetCSW(val byte)
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}
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func (c *I8259) IRR() byte {
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irr := c.irr
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// Reset the highest IR bit
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if irr&0x80 != 0 {
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c.irr &= 0x7F
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} else if irr&0x40 != 0 {
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c.irr &= 0x3F
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} else if irr&0x20 != 0 {
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c.irr &= 0x1F
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} else if irr&0x08 != 0 {
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c.irr &= 0x07
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} else if irr&0x04 != 0 {
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c.irr &= 0x03
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} else if irr&0x02 != 0 {
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c.irr &= 0x1
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} else {
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c.irr = 0
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}
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return irr
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}
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func (c *I8259) SetIRQ(irq byte) {
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if irq < 8 {
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c.irr |= 1 << irq
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} else {
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log.Warnf("SetIRQ out of range [0..7]: %d", irq)
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}
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}
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func (c *I8259) CSW() byte {
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return c.csw
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}
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func (c *I8259) SetCSW(val byte) {
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c.csw = val
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}
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func New() *I8259 {
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return &I8259{
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irr: 0,
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}
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}
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