izapple2/traceApplecorn.go

224 lines
5.3 KiB
Go

package izapple2
import (
"fmt"
)
/*
See:
https://github.com/bobbimanners/Applecorn
Chapter 45 https://raw.githubusercontent.com/bobbimanners/Applecorn/main/Manuals/Acorn%20BBC%20Micro%20User%20Guide.pdf
http://beebwiki.mdfs.net/Category:MOS_API
http://beebwiki.mdfs.net/OSBYTEs
http://mdfs.net/Docs/Comp/BBC/Osbyte00
*/
type traceApplecorn struct {
a *Apple2
skipConsole bool
osbyteNames [256]string
call mosCallData
wasInKernel bool
}
type mosCallData struct {
api uint16
a, x, y uint8
skipLog bool
}
const (
applecornKernelStart uint16 = 0xc000 // Code above this is out of BBC territory
applecornNoCaller uint16 = 0xffff
)
func newTraceApplecorn(a *Apple2, skipConsole bool) *traceApplecorn {
var t traceApplecorn
t.a = a
t.skipConsole = skipConsole
t.osbyteNames[0x7c] = "clear escape condition"
t.osbyteNames[0x7d] = "set escape condition"
t.osbyteNames[0x7e] = "ack detection of ESC"
t.osbyteNames[0x81] = "Read key with time lim"
t.osbyteNames[0x82] = "read high order address"
t.osbyteNames[0x83] = "read bottom of user mem"
t.osbyteNames[0x84] = "read top of user mem"
t.osbyteNames[0x85] = "top user mem for mode"
t.osbyteNames[0x86] = "read cursor pos"
t.osbyteNames[0xDA] = "clear VDU queue"
return &t
}
func (t *traceApplecorn) inspect() {
pc, _ := t.a.cpu.GetPCAndSP()
inKernel := pc >= applecornKernelStart
if !t.wasInKernel && inKernel {
regA, regX, regY, _ := t.a.cpu.GetAXYP()
s := "UNKNOWN"
skip := false
// Page 2 vectors
switch pc {
case t.vector(0x0208): // OSCLI vector
pc = 0xfff7
case t.vector(0x020A): // OSBYTE vector
pc = 0xfff4
case t.vector(0x020C): // OSWORD vector
pc = 0xfff1
case t.vector(0x020E): // OSWRCH vector
pc = 0xffee
case t.vector(0x0210): // OSRDCH vector
pc = 0xffe0
case t.vector(0x0212): // OSFILE vector
pc = 0xffdd
case t.vector(0x0214): // OSARGS vector
pc = 0xffda
case t.vector(0x0216): // OSBGET vector
pc = 0xffd7
case t.vector(0x0218): // OSBPUT vector
pc = 0xffd4
case t.vector(0x021A): // OSGBPB vector
pc = 0xffd1
case t.vector(0x021C): // OSFIND vector
pc = 0xffce
}
// Jump area
switch pc {
case 0xffb9:
s = "OSDRM(?)"
case 0xffbc:
s = "VDUCHR(?)"
case 0xffbf:
s = "OSEVEN(?)"
case 0xffc2:
s = "OSINIT(?)"
case 0xffc5:
s = "OSREAD(?)"
case 0xffc8:
ch := ""
if regA >= 0x20 && regA < 0x7f {
ch = string(regA)
}
s = fmt.Sprintf("OSNWRCH(A=%02x, '%v')", regA, ch)
skip = t.skipConsole
case 0xffcb:
s = "OSNRDCH()"
skip = t.skipConsole
case 0xffce:
s = "OSFIND(?)"
case 0xffd1:
s = "OSGBPB(?)"
case 0xffd4:
s = "OSBPUT(?)"
case 0xffd7:
s = "OSBGET(?)"
case 0xffda:
s = "OSARGS(?)"
case 0xffdd:
controlBlock := uint16(regX) + uint16(regY)<<8
filenameAddress := t.a.mmu.peekWord(controlBlock)
filename := t.getTerminatedString(filenameAddress, 0x0d)
s = fmt.Sprintf("OSFILE(A=%02x,FILE=%s)", regA, filename)
case 0xffe0:
s = "OSRDCH()"
skip = t.skipConsole
case 0xffe3: // This fallbacks to OSWRCH
s = "OSASCI(?)"
skip = t.skipConsole
case 0xffe7: // This fallbacks to OSWRCH
s = "OSNEWL()"
skip = t.skipConsole
case 0xffec: // This fallbacks to OSWRCH
skip = t.skipConsole
s = "OSNECR()"
case 0xffee:
ch := ""
if regA >= 0x20 && regA < 0x7f {
ch = string(regA)
}
s = fmt.Sprintf("OSWRCH(A=%02x, '%v')", regA, ch)
skip = t.skipConsole
case 0xfff1:
xy := uint16(regX) + uint16(regY)<<8
switch regA {
case 0: // Read line from input
lineAddress := t.a.mmu.peekWord(xy)
maxLength := t.a.mmu.Peek(xy + 2)
s = fmt.Sprintf("OSWORD('read line';A=%02x,XY=%04x,BUF=%04x,MAX=%02x)", regA, xy, lineAddress, maxLength)
default:
s = fmt.Sprintf("OSWORD(A=%02x,XY=%04x)", regA, xy)
}
case 0xfff4:
s = fmt.Sprintf("OSBYTE('%s';A=%02x,X=%02x,Y=%02x)", t.osbyteNames[regA], regA, regX, regY)
case 0xfff7:
xy := uint16(regX) + uint16(regY)<<8
command := t.getTerminatedString(xy, 0x0d)
s = fmt.Sprintf("OSCLI(\"%s\")", command)
}
if s == "UNKNOWN" && t.skipConsole {
// Let's also skip not known calls
skip = true
}
t.call.api = pc
t.call.a = regA
t.call.x = regX
t.call.y = regY
t.call.skipLog = skip
if !skip {
fmt.Printf("BBC MOS call to $%04x %s ", pc, s)
}
}
if t.wasInKernel && !inKernel && !t.call.skipLog {
// Returning from the call
regA, regX, regY, _ := t.a.cpu.GetAXYP()
s := ""
switch t.call.api {
case 0xfff1: // OSWORD
cbAddress := uint16(t.call.x) + uint16(t.call.y)<<8
switch t.call.a {
case 0: // Read line from input
lineAddress := t.a.mmu.peekWord(cbAddress)
line := t.getString(lineAddress, regY)
s = fmt.Sprintf(",line='%s'", line)
}
}
fmt.Printf("=> (A=%02x,X=%02x,Y=%02x%s)\n", regA, regX, regY, s)
}
t.wasInKernel = inKernel
}
func (t *traceApplecorn) getString(address uint16, length uint8) string {
s := ""
for i := uint8(0); i < length; i++ {
ch := t.a.mmu.Peek(address + uint16(i))
s = s + string(ch)
}
return s
}
func (t *traceApplecorn) getTerminatedString(address uint16, terminator uint8) string {
s := ""
for {
ch := t.a.mmu.Peek(address)
if ch == terminator {
break
}
s += string(ch)
address++
}
return s
}
func (t *traceApplecorn) vector(address uint16) uint16 {
return t.a.mmu.peekWord(address)
}