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cleanup

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This commit is contained in:
Michael Steil 2010-09-23 06:56:23 +00:00
parent 740d7b9f48
commit 134aeb7d51
1 changed files with 34 additions and 65 deletions
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99
perfect6502.c
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@ -31,7 +31,6 @@ enum {
STATE_GND,
STATE_FL,
STATE_PD,
STATE_UNDEFINED,
};
#define MAX_HIGH STATE_FH /* VCC, PU and FH are considered high */
@ -370,6 +369,12 @@ setHigh(nodenum_t nn)
setNode(nn, 1);
}
/************************************************************
*
* Address Bus and Data Bus Interface
*
************************************************************/
/* the nodes that make the data bus */
const nodenum_t dbnodes[8] = { db0, db1, db2, db3, db4, db5, db6, db7 };
@ -383,6 +388,7 @@ writeDataBus(uint8_t x)
x >>= 1;
}
/* recalc all nodes connected starting from the data bus */
nodenum_t list[NODES];
bcopy(dbnodes, list, sizeof(dbnodes));
recalcNodeList(list, 8);
@ -416,13 +422,6 @@ readAddressBus()
(isNodeHigh(ab15) << 15);
}
void
handleBusRead()
{
if (isNodeHigh(rw))
writeDataBus(mRead(readAddressBus()));
}
uint8_t
readDataBus()
{
@ -444,16 +443,12 @@ mWrite(uint16_t a, uint8_t d)
memory[a] = d;
}
void
handleBusWrite()
{
if (!isNodeHigh(rw)) {
uint16_t a = readAddressBus();
uint8_t d = readDataBus();
mWrite(a,d);
}
}
/************************************************************
*
* Tracing/Debugging
*
************************************************************/
uint8_t
readA()
{
@ -580,63 +575,37 @@ chipStatus()
readSP(),
readP(),
readNOTIR() ^ 0xFF);
#if 0
var machine1 =
' halfcyc:' + cycle +
' phi0:' + readBit('clk0') +
' AB:' + hexWord(ab) +
' D:' + hexByte(readDataBus()) +
' RnW:' + readBit('rw');
var machine2 =
' PC:' + hexWord(readPC()) +
' A:' + hexByte(readA()) +
' X:' + hexByte(readX()) +
' Y:' + hexByte(readY()) +
' SP:' + hexByte(readSP()) +
' ' + readPstring();
var machine3 =
' Sync:' + readBit('sync')
' IRQ:' + readBit('irq') +
' NMI:' + readBit('nmi');
var machine4 =
' IR:' + hexByte(255 - readBits('notir', 8)) +
' idl:' + hexByte(255 - readBits('idl', 8)) +
' alu:' + hexByte(255 - readBits('alu', 8)) +
' TCstate:' + readBit('clock1') + readBit('clock2') +
readBit('t2') + readBit('t3') + readBit('t4') + readBit('t5');
var machine5 =
' notRdy0:' + readBit('notRdy0') +
' fetch:' + readBit('fetch') +
' clearIR:' + readBit('clearIR') +
' D1x1:' + readBit('D1x1');
setStatus(machine1 + "<br>" + machine2);
if (loglevel>2 && ctrace) {
console.log(machine1 + " " + machine2 + " " + machine3 + " " + machine4 + " " + machine5);
}
#endif
}
/************************************************************
*
* Main CLock Loop
*
************************************************************/
void
halfStep()
{
#ifdef DEBUG
printf("%s\n", __func__);
#endif
if (isNodeHigh(clk0)) {
setLow(clk0);
handleBusRead();
} else {
setHigh(clk0);
handleBusWrite();
}
BOOL clk = isNodeHigh(clk0);
setNode(clk0, !clk);
if (clk && isNodeHigh(rw))
writeDataBus(mRead(readAddressBus()));
if (!clk && !isNodeHigh(rw))
mWrite(readAddressBus(), readDataBus());
}
/************************************************************
*
* Initialization
*
************************************************************/
void
initChip()
{
#ifdef DEBUG
printf("%s\n", __func__);
#endif
nodenum_t nn;
for (nn = 0; nn < NODES; nn++)
nodes_state[nn] = STATE_FL;