Mercurial > avr_jtag

diff src/jtag.c @ 4:6b1594fb668f

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Improve performance of jtag.c and test it with Python scripts. - cp_tditdo.py send bits to TDI and hope it will feed back from TDO. - Expand loops in jtag.c to improve performance.
author Thinker K.F. Li <thinker@branda.to>
date Sun, 22 Feb 2009 12:54:45 +0800
parents abf221bf3ce4
children eb14cac68cbb
line wrap: on
line diff
--- a/src/jtag.c	Sun Feb 22 01:40:36 2009 +0800
+++ b/src/jtag.c	Sun Feb 22 12:54:45 2009 +0800
@@ -4,7 +4,7 @@
 #include "avriotools.h"
 
 /* It is supposed to work at 1Mbps */
-#define CLK_DELAY() do { _delay_ms(0.0004); } while(0)
+#define CLK_DELAY()
 
 void jtag_init(void) {
     pin_mode(&JTAG_PORT, JTAG_TCK, PM_OUTPUT);
@@ -21,9 +21,9 @@
 #define SEND_BIT(pin, bit)			\
     do {					\
 	if(bit)					\
-	    pin_hi(JTAG_PORT, JTAG_TDI);	\
+	    pin_hi(JTAG_PORT, pin);		\
 	else					\
-	    pin_lo(JTAG_PORT, JTAG_TDI);	\
+	    pin_lo(JTAG_PORT, pin);		\
 	CLK_DELAY();				\
 	TCK_HI();				\
 	CLK_DELAY();				\
@@ -32,13 +32,51 @@
 
 void jtag_tms(char *buf, int nbits) {
     int i;
+    int nbytes, byte;
     int byteoff, bitoff;
     int bit;
     
+    nbytes = nbits / 8;
+    for(i = 0; i < nbytes; i++) {
+	byte = buf[i];
+	
+	bit = byte & 0x01;
+	SEND_BIT(JTAG_TMS, bit);
+	TCK_LO();
+	
+	bit = byte & 0x02;
+	SEND_BIT(JTAG_TMS, bit);
+	TCK_LO();
+	
+	bit = byte & 0x04;
+	SEND_BIT(JTAG_TMS, bit);
+	TCK_LO();
+	
+	bit = byte & 0x08;
+	SEND_BIT(JTAG_TMS, bit);
+	TCK_LO();
+	
+	bit = byte & 0x10;
+	SEND_BIT(JTAG_TMS, bit);
+	TCK_LO();
+	
+	bit = byte & 0x20;
+	SEND_BIT(JTAG_TMS, bit);
+	TCK_LO();
+	
+	bit = byte & 0x40;
+	SEND_BIT(JTAG_TMS, bit);
+	TCK_LO();
+	
+	bit = byte & 0x80;
+	SEND_BIT(JTAG_TMS, bit);
+	TCK_LO();
+    }
+    
+    byte = buf[i];
+    nbits %= 8;
     for(i = 0; i < nbits; i++) {
-	byteoff = i / 8;
-	bitoff = i % 8;
-	bit = buf[byteoff] & (1 << bitoff);
+	bit = byte & (1 << i);
 	SEND_BIT(JTAG_TMS, bit);
 	TCK_LO();
     }
@@ -46,35 +84,159 @@
 
 void jtag_shift(char *buf, int nbits) {
     int i;
+    int nbytes, byte;
     int byteoff, bitoff;
     int bit;
     
-    for(i = 0; i < nbits; i++) {
-	byteoff = i / 8;
-	bitoff = i % 8;
-	bit = buf[byteoff] & (1 << bitoff);
+    nbytes = nbits / 8;
+    for(i = 0; i < nbytes; i++) {
+	byte = buf[i];
+	
+	bit = byte & 0x01;
+	SEND_BIT(JTAG_TDI, bit);
+	TCK_LO();
+	
+	bit = byte & 0x02;
+	SEND_BIT(JTAG_TDI, bit);
+	TCK_LO();
+	
+	bit = byte & 0x04;
+	SEND_BIT(JTAG_TDI, bit);
+	TCK_LO();
+	
+	bit = byte & 0x08;
+	SEND_BIT(JTAG_TDI, bit);
+	TCK_LO();
+	
+	bit = byte & 0x10;
 	SEND_BIT(JTAG_TDI, bit);
 	TCK_LO();
+	
+	bit = byte & 0x20;
+	SEND_BIT(JTAG_TDI, bit);
+	TCK_LO();
+	
+	bit = byte & 0x40;
+	SEND_BIT(JTAG_TDI, bit);
+	TCK_LO();
+	
+	bit = byte & 0x80;
+	SEND_BIT(JTAG_TDI, bit);
+	TCK_LO();
+    }
+    
+    nbits %= 8;
+    if(nbits) {
+	byte = buf[i];
+	for(i = 0; i < nbits; i++) {
+	    bit = byte & (1 << i);
+	    SEND_BIT(JTAG_TDI, bit);
+	    TCK_LO();
+	}
     }
 }
 
 void jtag_shift_inout(char *ibuf, char *obuf, int nbits) {
-    int i;
+    int i, j;
+    int nbytes, byte, obyte;
+    int tdo;
     int byteoff, bitoff;
-    int bit, tdo, bitmask;
+    int bit;
     
-    for(i = 0; i < nbits; i++) {
-	byteoff = i / 8;
-	bitoff = i % 8;
-	bitmask = 1 << bitoff;
+    nbytes = nbits / 8;
+    for(i = 0; i < nbytes; i++) {
+	byte = ibuf[i];
+	obyte = 0;
+	
+	bit = byte & 0x01;
+	SEND_BIT(JTAG_TDI, bit);
+	tdo = GET_TDO();
+	if(tdo)
+	    obyte |= 0x01;
+	else
+	    obyte &= ~0x01;
+	TCK_LO();
 	
-	bit = ibuf[byteoff] & bitmask;
+	bit = byte & 0x02;
+	SEND_BIT(JTAG_TDI, bit);
+	tdo = GET_TDO();
+	if(tdo)
+	    obyte |= 0x02;
+	else
+	    obyte &= ~0x02;
+	TCK_LO();
+	
+	bit = byte & 0x04;
+	SEND_BIT(JTAG_TDI, bit);
+	tdo = GET_TDO();
+	if(tdo)
+	    obyte |= 0x04;
+	else
+	    obyte &= ~0x04;
+	TCK_LO();
+	
+	bit = byte & 0x08;
+	SEND_BIT(JTAG_TDI, bit);
+	tdo = GET_TDO();
+	if(tdo)
+	    obyte |= 0x08;
+	else
+	    obyte &= ~0x08;
+	TCK_LO();
+	
+	bit = byte & 0x10;
 	SEND_BIT(JTAG_TDI, bit);
 	tdo = GET_TDO();
+	if(tdo)
+	    obyte |= 0x10;
+	else
+	    obyte &= ~0x10;
 	TCK_LO();
+	
+	bit = byte & 0x20;
+	SEND_BIT(JTAG_TDI, bit);
+	tdo = GET_TDO();
+	if(tdo)
+	    obyte |= 0x20;
+	else
+	    obyte &= ~0x20;
+	TCK_LO();
+	
+	bit = byte & 0x40;
+	SEND_BIT(JTAG_TDI, bit);
+	tdo = GET_TDO();
 	if(tdo)
-	    obuf[byteoff] |= bitmask;
+	    obyte |= 0x40;
+	else
+	    obyte &= ~0x40;
+	TCK_LO();
+	
+	bit = byte & 0x80;
+	SEND_BIT(JTAG_TDI, bit);
+	tdo = GET_TDO();
+	if(tdo)
+	    obyte |= 0x80;
 	else
-	    obuf[byteoff] &= ~(bitmask);
+	    obyte &= ~0x80;
+	TCK_LO();
+
+	obuf[i] = obyte;
+    }
+    
+    nbits %= 8;
+    if(nbits) {
+	byte = ibuf[i];
+	obyte = 0;
+	for(j = 0; j < nbits; j++) {
+	    bit = byte & (1 << j);
+	    SEND_BIT(JTAG_TDI, bit);
+	    tdo = GET_TDO();
+	    if(tdo)
+		obyte |= 1 << j;
+	    else
+		obyte &= ~(1 << j);
+	    TCK_LO();
+	}
+	obuf[i] = obyte;
     }
 }