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Firmware: remove superfluous delays

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Change-Id: I5c8c5ba9ea87458c05a229973672503bd1aa6100
This commit is contained in:
David Banks 2019-11-04 11:38:02 +00:00
parent 86b8e219eb
commit dd8116b364
1 changed files with 14 additions and 31 deletions
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45
firmware/AtomBusMon.c
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@ -456,7 +456,7 @@ void hwCmd(unsigned int cmd, unsigned int param) {
unsigned int hwRead8(unsigned int offset) { unsigned int hwRead8(unsigned int offset) {
MUXSEL_PORT &= ~MUXSEL_MASK; MUXSEL_PORT &= ~MUXSEL_MASK;
MUXSEL_PORT |= offset << MUXSEL_BIT; MUXSEL_PORT |= offset << MUXSEL_BIT;
Delay_us(1); Delay_us(1); // fixed 1us delay is needed here
return MUX_DIN; return MUX_DIN;
} }
@ -465,10 +465,10 @@ unsigned int hwRead16(unsigned int offset) {
unsigned int lsb; unsigned int lsb;
MUXSEL_PORT &= ~MUXSEL_MASK; MUXSEL_PORT &= ~MUXSEL_MASK;
MUXSEL_PORT |= offset << MUXSEL_BIT; MUXSEL_PORT |= offset << MUXSEL_BIT;
Delay_us(1); Delay_us(1); // fixed 1us delay is needed here
lsb = MUX_DIN; lsb = MUX_DIN;
MUXSEL_PORT |= 1 << MUXSEL_BIT; MUXSEL_PORT |= 1 << MUXSEL_BIT;
Delay_us(1); Delay_us(1); // fixed 1us delay is needed here
return (MUX_DIN << 8) | lsb; return (MUX_DIN << 8) | lsb;
} }
@ -522,13 +522,11 @@ void loadAddr(unsigned int addr) {
unsigned int readMemByte() { unsigned int readMemByte() {
hwCmd(CMD_RD_MEM, 0); hwCmd(CMD_RD_MEM, 0);
Delay_us(10);
return hwRead8(OFFSET_DATA); return hwRead8(OFFSET_DATA);
} }
unsigned int readMemByteInc() { unsigned int readMemByteInc() {
hwCmd(CMD_RD_MEM_INC, 0); hwCmd(CMD_RD_MEM_INC, 0);
Delay_us(10);
return hwRead8(OFFSET_DATA); return hwRead8(OFFSET_DATA);
} }
@ -542,13 +540,11 @@ void writeMemByteInc() {
unsigned int readIOByte() { unsigned int readIOByte() {
hwCmd(CMD_RD_IO, 0); hwCmd(CMD_RD_IO, 0);
Delay_us(10);
return hwRead8(OFFSET_DATA); return hwRead8(OFFSET_DATA);
} }
unsigned int readIOByteInc() { unsigned int readIOByteInc() {
hwCmd(CMD_RD_IO_INC, 0); hwCmd(CMD_RD_IO_INC, 0);
Delay_us(10);
return hwRead8(OFFSET_DATA); return hwRead8(OFFSET_DATA);
} }
@ -932,7 +928,6 @@ int pollForEvents() {
if (STATUS_DIN & BW_ACTIVE_MASK) { if (STATUS_DIN & BW_ACTIVE_MASK) {
cont = logDetails(); cont = logDetails();
hwCmd(CMD_WATCH_READ, 0); hwCmd(CMD_WATCH_READ, 0);
Delay_us(10);
} }
if (Serial_ByteRecieved0()) { if (Serial_ByteRecieved0()) {
// Interrupt on a return, ignore other characters // Interrupt on a return, ignore other characters
@ -943,6 +938,15 @@ int pollForEvents() {
return cont; return cont;
} }
// Applies a fixed 1ms long reset pulse to the CPU
// This should be good for clock rates down to ~10KHz
void resetCpu() {
log0("Resetting CPU\n");
hwCmd(CMD_RESET, 1);
Delay_us(1000);
hwCmd(CMD_RESET, 0);
}
/******************************************* /*******************************************
* User Commands * User Commands
*******************************************/ *******************************************/
@ -978,7 +982,6 @@ void doCmdStep(char *params) {
i = instructions; i = instructions;
} }
if (i == instructions || (trace && (--j == 0))) { if (i == instructions || (trace && (--j == 0))) {
Delay_us(10);
logAddr(); logAddr();
j = trace; j = trace;
} }
@ -986,24 +989,7 @@ void doCmdStep(char *params) {
} }
void doCmdReset(char *params) { void doCmdReset(char *params) {
log0("Resetting CPU\n"); resetCpu();
#if defined(CPU_6502) || defined(CPU_65C02)
// For the 6502 cores, to get the single stepping to stop correctly
// on the first instruction after reset, it helps to assert reset twice.
// I haven't looked into why this is, as it doesn't seem very important.
// It's mostly cosmetic, but nice on the Atom to consisently show FF3F.
int i;
for (i = 0; i < 2; i++) {
#endif
hwCmd(CMD_RESET, 1);
Delay_us(50);
hwCmd(CMD_STEP, 0);
Delay_us(50);
hwCmd(CMD_RESET, 0);
Delay_us(50);
#if defined(CPU_6502) || defined(CPU_65C02)
}
#endif
logAddr(); logAddr();
} }
@ -1347,10 +1333,7 @@ void doCmdContinue(char *params) {
// Reset if required // Reset if required
if (reset) { if (reset) {
log0("Resetting CPU\n"); resetCpu();
hwCmd(CMD_RESET, 1);
Delay_us(100);
hwCmd(CMD_RESET, 0);
} }
// Wait for breakpoint to become active // Wait for breakpoint to become active