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simplified state

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This commit is contained in:
Michael Steil 2010-09-24 10:15:54 +00:00
parent 178d216ae9
commit e3042fd534
1 changed files with 26 additions and 36 deletions
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62
perfect6502.c
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@ -62,15 +62,13 @@ typedef int BOOL;
*
************************************************************/
enum {
STATE_VCC, /* node is VCC */
STATE_PU, /* node is connected to VCC */
STATE_FH, /* node was connected to VCC */
#define isNodeHigh(nn) (nodes_state[nn] <= STATE_FH) /* everything above is high */
STATE_GND, /* node is GND */
STATE_PD, /* node is connexted to GND */
STATE_FL, /* node was connected to GND */
};
#define STATE_0 0
#define STATE_1 1
#define STATE_FLOATING 2
#define STATE_0_FLOATING (STATE_0 | STATE_FLOATING)
#define STATE_1_FLOATING (STATE_1 | STATE_FLOATING)
#define isNodeHigh(nn) (nodes_state[nn] & 1)
/* the smallest types to fit the numbers */
typedef uint16_t nodenum_t;
@ -313,34 +311,34 @@ addNodeToGroup(nodenum_t i)
}
/*
* 1. if the group is connected to GND, it's STATE_GND
* 2. if the group is connected to VCC, it's STATE_VCC
* 3a. if there is a pullup node, it's STATE_PU
* 3b. if there is a pulldown node, it's STATE_PD
* 1. if the group is connected to GND, it's STATE_0
* 2. if the group is connected to VCC, it's STATE_1
* 3a. if there is a pullup node, it's STATE_1
* 3b. if there is a pulldown node, it's STATE_0
* (if both 1 and 2 are true, the first pullup or pulldown wins, with
* a statistical advantage towards STATE_PU)
* 4. otherwise, if there is an FH node, it's STATE_FH
* 5. otherwise, it's STATE_FL (if there is an FL node, which is always the case)
* a statistical advantage towards STATE_1)
* 4. otherwise, if there is an FH node, it's STATE_1_FLOATING
* 5. otherwise, it's STATE_0_FLOATING (if there is an FL node, which is always the case)
*/
state_t
getNodeValue()
{
if (group_contains(vss))
return STATE_GND;
return STATE_0;
if (group_contains(vcc))
return STATE_VCC;
return STATE_1;
state_t flstate = STATE_FL;
state_t flstate = STATE_0_FLOATING;
for (count_t i = 0; i < group_count(); i++) {
nodenum_t nn = group_get(i);
if (get_nodes_pullup(nn))
return STATE_PU;
return STATE_1;
if (get_nodes_pulldown(nn))
return STATE_PD;
if (nodes_state[nn] == STATE_FH)
flstate = STATE_FH;
return STATE_0;
if (nodes_state[nn] == STATE_1_FLOATING)
flstate = STATE_1_FLOATING;
}
return flstate;
}
@ -364,16 +362,8 @@ void
floatnode(nodenum_t nn)
{
/* VCC and GND are constant */
if (nn == vss || nn == vcc)
return;
state_t state = nodes_state[nn];
if (state == STATE_GND || state == STATE_PD)
nodes_state[nn] = STATE_FL;
if (state == STATE_VCC || state == STATE_PU)
nodes_state[nn] = STATE_FH;
if (nn != vss && nn != vcc)
nodes_state[nn] |= STATE_FLOATING;
}
void
@ -854,8 +844,8 @@ setupNodesAndTransistors()
nodes_c1c2s[c1][nodes_c1c2count[c1]++] = i;
nodes_c1c2s[c2][nodes_c1c2count[c2]++] = i;
}
nodes_state[vss] = STATE_GND;
nodes_state[vcc] = STATE_VCC;
nodes_state[vss] = STATE_0;
nodes_state[vcc] = STATE_1;
}
void
@ -863,7 +853,7 @@ initChip()
{
/* all nodes are floating */
for (nodenum_t nn = 0; nn < NODES; nn++)
nodes_state[nn] = STATE_FL;
nodes_state[nn] = STATE_0_FLOATING;
/* all transistors are off */
for (transnum_t tn = 0; tn < TRANSISTORS; tn++)
set_transistors_on(tn, NO);