diff --git a/ChangeLog b/ChangeLog
index fc412090..eddb33ed 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,18 @@
+2006-08-17 Joerg Wunsch <j@uriah.heep.sax.de>
+
+ Submitted by Neil Davey:
+ patch #4539: Ability to control the bit clock (usleep) delay
+ for ppi interface
+ * bitbang.c: Implement bitbang_delay() and its calibration.
+ * bitbang.h: Declare bitbang_delay().
+ * main.c: Add the ispdelay option (-i).
+ * pgm.h (struct programmer_t): Add the ispdelay parameter.
+ * par.c: Add calls to bitbang_delay() when requested.
+ * serbb_posix.c: (Ditto.)
+ * serbb_win32.c: (Ditto.)
+ * avrdude.1: Document the new -i option.
+ * doc/avrdude.texi: (Ditto.)
+
2006-08-14 Joerg Wunsch <j@uriah.heep.sax.de>
Submitted by <chris@awaretechs.com>:
diff --git a/NEWS b/NEWS
index c7aee8b3..8e43b640 100644
--- a/NEWS
+++ b/NEWS
@@ -22,6 +22,9 @@ Current:
* Add high-voltage mode programming for the STK500 (both,
parallel, and high-voltage serial programming).
+ * Allow for specifying the ISP clock delay as an option for
+ bit-bang programming adapters.
+
Version 5.1:
* New devices supported:
diff --git a/avrdude.1 b/avrdude.1
index 94fa5977..3e86ed4a 100644
--- a/avrdude.1
+++ b/avrdude.1
@@ -19,7 +19,7 @@
.\"
.\" $Id$
.\"
-.Dd DATE July 19, 2006
+.Dd DATE August 16, 2006
.Os
.Dt AVRDUDE 1
.Sh NAME
@@ -38,6 +38,7 @@
.Op \&, Ns Ar exitspec
.Oc
.Op Fl F
+.Op Fl i Ar delay
.Op Fl n
.Op Fl P Ar port
.Op Fl q
@@ -330,6 +331,24 @@ reasonable before continuing. Since it can happen from time to time
that a device has a broken (erased or overwritten) device signature
but is otherwise operating normally, this options is provided to
override the check.
+.It Fl i Ar delay
+For bitbang-type programmers, delay for approximately
+.Ar delay
+microseconds between each bit state change.
+If the host system is very fast, or the target runs off a slow clock
+(like a 32 kHz crystal, or the 128 kHz internal RC oscillator), this
+can become necessary to satisfy the requirement that the ISP clock
+frequency must not be higher than 1/4 of the CPU clock frequency.
+This is implemented as a spin-loop delay to allow even for very
+short delays.
+On Unix-style operating systems, the spin loop is initially calibrated
+against a system timer, so the number of microseconds might be rather
+realistic, assuming a constant system load while
+.Nm
+is running.
+On Win32 operating systems, a preconfigured number of cycles per
+microsecond is assumed that might be off a bit for very fast or very
+slow machines.
.It Fl n
No-write - disables actually writing data to the MCU (useful for debugging
.Nm avrdude
diff --git a/bitbang.c b/bitbang.c
index 6cbb1689..e6102c7f 100644
--- a/bitbang.c
+++ b/bitbang.c
@@ -28,18 +28,103 @@
#include <unistd.h>
#include <errno.h>
+#if !defined(WIN32NATIVE)
+# include <signal.h>
+# include <sys/time.h>
+#endif
+
#include "avr.h"
#include "pindefs.h"
#include "pgm.h"
#include "par.h"
#include "serbb.h"
-#define SLOW_TOGGLE 0
-
extern char * progname;
extern int do_cycles;
extern int verbose;
+static int delay_decrement;
+
+#if !defined(WIN32NATIVE)
+static volatile int done;
+
+typedef void (*mysighandler_t)(int);
+static mysighandler_t saved_alarmhandler;
+
+static void alarmhandler(int signo)
+{
+ done = 1;
+ signal(SIGALRM, saved_alarmhandler);
+}
+#endif /* !WIN32NATIVE */
+
+/*
+ * Calibrate the microsecond delay loop below.
+ */
+static void bitbang_calibrate_delay(void)
+{
+ /*
+ * Right now, we don't have any Win32 implementation for this, so we
+ * can only run on a preconfigured delay stepping there. The figure
+ * below should at least be correct within an order of magnitude,
+ * judging from the auto-calibration figures seen on various Unix
+ * systems on comparable hardware.
+ */
+#if defined(WIN32NATIVE)
+ delay_decrement = 100;
+#else /* !WIN32NATIVE */
+ struct itimerval itv;
+ volatile int i;
+
+ if (verbose >= 2)
+ fprintf(stderr,
+ "%s: Calibrating delay loop...",
+ progname);
+ i = 0;
+ done = 0;
+ saved_alarmhandler = signal(SIGALRM, alarmhandler);
+ /*
+ * Set ITIMER_REAL to 100 ms. All known systems have a timer
+ * granularity of 10 ms or better, so counting the delay cycles
+ * accumulating over 100 ms should give us a rather realistic
+ * picture, without annoying the user by a lengthy startup time (as
+ * an alarm(1) would do). Of course, if heavy system activity
+ * happens just during calibration but stops before the remaining
+ * part of AVRDUDE runs, this will yield wrong values. There's not
+ * much we can do about this.
+ */
+ itv.it_value.tv_sec = 0;
+ itv.it_value.tv_usec = 100000;
+ itv.it_interval.tv_sec = itv.it_interval.tv_usec = 0;
+ setitimer(ITIMER_REAL, &itv, 0);
+ while (!done)
+ i--;
+ itv.it_value.tv_sec = itv.it_value.tv_usec = 0;
+ setitimer(ITIMER_REAL, &itv, 0);
+ /*
+ * Calculate back from 100 ms to 1 us.
+ */
+ delay_decrement = -i / 100000;
+ if (verbose >= 2)
+ fprintf(stderr,
+ " calibrated to %d cycles per us\n",
+ delay_decrement);
+#endif /* WIN32NATIVE */
+}
+
+/*
+ * Delay for approximately the number of microseconds specified.
+ * usleep()'s granularity is usually like 1 ms or 10 ms, so it's not
+ * really suitable for short delays in bit-bang algorithms.
+ */
+void bitbang_delay(int us)
+{
+ volatile int del = us * delay_decrement;
+
+ while (del > 0)
+ del--;
+}
+
/*
* transmit and receive a byte of data to/from the AVR device
*/
@@ -204,6 +289,8 @@ int bitbang_initialize(PROGRAMMER * pgm, AVRPART * p)
int rc;
int tries;
+ bitbang_calibrate_delay();
+
pgm->powerup(pgm);
usleep(20000);
diff --git a/bitbang.h b/bitbang.h
index b428e604..90f0d481 100644
--- a/bitbang.h
+++ b/bitbang.h
@@ -25,6 +25,7 @@
int bitbang_setpin(int fd, int pin, int value);
int bitbang_getpin(int fd, int pin);
int bitbang_highpulsepin(int fd, int pin);
+void bitbang_delay(unsigned int us);
int bitbang_rdy_led (PROGRAMMER * pgm, int value);
int bitbang_err_led (PROGRAMMER * pgm, int value);
diff --git a/doc/avrdude.texi b/doc/avrdude.texi
index 5f304a47..1babea75 100644
--- a/doc/avrdude.texi
+++ b/doc/avrdude.texi
@@ -584,6 +584,23 @@ to time that a device has a broken (erased or overwritten) device
signature but is otherwise operating normally, this options is provided
to override the check.
+@item -i @var{delay}
+For bitbang-type programmers, delay for approximately
+@var{delay}
+microseconds between each bit state change.
+If the host system is very fast, or the target runs off a slow clock
+(like a 32 kHz crystal, or the 128 kHz internal RC oscillator), this
+can become necessary to satisfy the requirement that the ISP clock
+frequency must not be higher than 1/4 of the CPU clock frequency.
+This is implemented as a spin-loop delay to allow even for very
+short delays.
+On Unix-style operating systems, the spin loop is initially calibrated
+against a system timer, so the number of microseconds might be rather
+realistic, assuming a constant system load while AVRDUDE is running.
+On Win32 operating systems, a preconfigured number of cycles per
+microsecond is assumed that might be off a bit for very fast or very
+slow machines.
+
@item -n
No-write - disables actually writing data to the MCU (useful for
debugging AVRDUDE).
diff --git a/main.c b/main.c
index b0a2bee3..64a11e7a 100644
--- a/main.c
+++ b/main.c
@@ -105,6 +105,7 @@ void usage(void)
" -C <config-file> Specify location of configuration file.\n"
" -c <programmer> Specify programmer type.\n"
" -D Disable auto erase for flash memory\n"
+ " -i <delay> ISP Clock Delay [in microseconds]\n"
" -P <port> Specify connection port.\n"
" -F Override invalid signature check.\n"
" -e Perform a chip erase.\n"
@@ -695,6 +696,7 @@ int main(int argc, char * argv [])
char * e; /* for strtol() error checking */
int baudrate; /* override default programmer baud rate */
double bitclock; /* Specify programmer bit clock (JTAG ICE) */
+ int ispdelay; /* Specify the delay for ISP clock */
int safemode; /* Enable safemode, 1=safemode on, 0=normal */
int silentsafe; /* Don't ask about fuses, 1=silent, 0=normal */
unsigned char safemode_lfuse = 0xff;
@@ -752,6 +754,7 @@ int main(int argc, char * argv [])
set_cycles = -1;
baudrate = 0;
bitclock = 0.0;
+ ispdelay = 0;
safemode = 1; /* Safemode on by default */
silentsafe = 0; /* Ask by default */
@@ -802,7 +805,7 @@ int main(int argc, char * argv [])
/*
* process command line arguments
*/
- while ((ch = getopt(argc,argv,"?b:B:c:C:DeE:Fnp:P:qstU:uvVyY:")) != -1) {
+ while ((ch = getopt(argc,argv,"?b:B:c:C:DeE:Fi:np:P:qstU:uvVyY:")) != -1) {
switch (ch) {
case 'b': /* override default programmer baud rate */
@@ -823,6 +826,15 @@ int main(int argc, char * argv [])
}
break;
+ case 'i': /* specify isp clock delay */
+ ispdelay = strtol(optarg, &e,10);
+ if ((e == optarg) || (*e != 0) || ispdelay == 0) {
+ fprintf(stderr, "%s: invalid isp clock delay specified '%s'\n",
+ progname, optarg);
+ exit(1);
+ }
+ break;
+
case 'c': /* programmer id */
programmer = optarg;
break;
@@ -1133,6 +1145,13 @@ int main(int argc, char * argv [])
pgm->bitclock = bitclock * 1e-6;
}
+ if (ispdelay != 0) {
+ if (verbose) {
+ fprintf(stderr, "%sSetting isp clock delay: %3i\n", progbuf, ispdelay);
+ }
+ pgm->ispdelay = ispdelay;
+ }
+
rc = pgm->open(pgm, port);
if (rc < 0) {
exitrc = 1;
diff --git a/par.c b/par.c
index 7b7766d5..7cc30ff4 100644
--- a/par.c
+++ b/par.c
@@ -48,8 +48,6 @@ extern int verbose;
#if HAVE_PARPORT
-#define SLOW_TOGGLE 0
-
struct ppipins_t {
int pin;
int reg;
@@ -102,9 +100,8 @@ static int par_setpin(PROGRAMMER * pgm, int pin, int value)
else
ppi_clr(pgm->fd, ppipins[pin].reg, ppipins[pin].bit);
-#if SLOW_TOGGLE
- usleep(1000);
-#endif
+ if (pgm->ispdelay > 1)
+ bitbang_delay(pgm->ispdelay);
return 0;
}
@@ -155,24 +152,20 @@ static int par_highpulsepin(PROGRAMMER * pgm, int pin)
if (inverted) {
ppi_clr(pgm->fd, ppipins[pin].reg, ppipins[pin].bit);
-#if SLOW_TOGGLE
- usleep(1000);
-#endif
- ppi_set(pgm->fd, ppipins[pin].reg, ppipins[pin].bit);
+ if (pgm->ispdelay > 1)
+ bitbang_delay(pgm->ispdelay);
-#if SLOW_TOGGLE
- usleep(1000);
-#endif
+ ppi_set(pgm->fd, ppipins[pin].reg, ppipins[pin].bit);
+ if (pgm->ispdelay > 1)
+ bitbang_delay(pgm->ispdelay);
} else {
ppi_set(pgm->fd, ppipins[pin].reg, ppipins[pin].bit);
-#if SLOW_TOGGLE
- usleep(1000);
-#endif
- ppi_clr(pgm->fd, ppipins[pin].reg, ppipins[pin].bit);
+ if (pgm->ispdelay > 1)
+ bitbang_delay(pgm->ispdelay);
-#if SLOW_TOGGLE
- usleep(1000);
-#endif
+ ppi_clr(pgm->fd, ppipins[pin].reg, ppipins[pin].bit);
+ if (pgm->ispdelay > 1)
+ bitbang_delay(pgm->ispdelay);
}
return 0;
diff --git a/pgm.h b/pgm.h
index f03fdbb2..be4bd105 100644
--- a/pgm.h
+++ b/pgm.h
@@ -48,6 +48,7 @@ typedef struct programmer_t {
int ppictrl;
int baudrate;
double bitclock; /* JTAG ICE clock period in microseconds */
+ int ispdelay; /* ISP clock delay */
int fd;
int page_size; /* page size if the programmer supports paged write/load */
int (*rdy_led) (struct programmer_t * pgm, int value);
diff --git a/serbb_posix.c b/serbb_posix.c
index b023df59..b78cddae 100644
--- a/serbb_posix.c
+++ b/serbb_posix.c
@@ -158,14 +158,12 @@ static int serbb_highpulsepin(PROGRAMMER * pgm, int pin)
return -1;
serbb_setpin(pgm, pin, 1);
- #if SLOW_TOGGLE
- usleep(1000);
- #endif
- serbb_setpin(pgm, pin, 0);
+ if (pgm->ispdelay > 1)
+ bitbang_delay(pgm->ispdelay);
- #if SLOW_TOGGLE
- usleep(1000);
- #endif
+ serbb_setpin(pgm, pin, 0);
+ if (pgm->ispdelay > 1)
+ bitbang_delay(pgm->ispdelay);
return 0;
}
diff --git a/serbb_win32.c b/serbb_win32.c
index 9829a7e9..e4cd95d5 100644
--- a/serbb_win32.c
+++ b/serbb_win32.c
@@ -230,14 +230,12 @@ static int serbb_highpulsepin(PROGRAMMER * pgm, int pin)
return -1;
serbb_setpin(pgm, pin, 1);
-#if SLOW_TOGGLE
- usleep(1000);
-#endif
- serbb_setpin(pgm, pin, 0);
+ if (pgm->ispdelay > 1)
+ bitbang_delay(pgm->ispdelay);
-#if SLOW_TOGGLE
- usleep(1000);
-#endif
+ serbb_setpin(pgm, pin, 0);
+ if (pgm->ispdelay > 1)
+ bitbang_delay(pgm->ispdelay);
return 0;
}