/*
* avrdude - A Downloader/Uploader for AVR device programmers
* Copyright (C) 2000, 2001, 2002, 2003 Brian S. Dean <bsd@bsdhome.com>
* Copyright (C) 2005 Michael Holzt <kju-avr@fqdn.org>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
/* $Id$ */
#include "ac_cfg.h"
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <fcntl.h>
#include <unistd.h>
#include <errno.h>
#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 bitbang_setpin(PROGRAMMER * pgm, int pin, int value)
{
if ( pgm->flag )
serbb_setpin(pgm->fd,pin,value);
else
par_setpin(pgm->fd,pin,value);
return 0;
}
static int bitbang_getpin(PROGRAMMER * pgm, int pin)
{
if ( pgm->flag )
return serbb_getpin(pgm->fd,pin);
else
return par_getpin(pgm->fd,pin);
}
static int bitbang_highpulsepin(PROGRAMMER * pgm, int pin)
{
if ( pgm->flag )
return serbb_highpulsepin(pgm->fd,pin);
else
return par_highpulsepin(pgm->fd,pin);
}
/*
* transmit and receive a byte of data to/from the AVR device
*/
static unsigned char bitbang_txrx(PROGRAMMER * pgm, unsigned char byte)
{
int i;
unsigned char r, b, rbyte;
rbyte = 0;
for (i=7; i>=0; i--) {
/*
* Write and read one bit on SPI.
* Some notes on timing: Let T be the time it takes to do
* one bitbang_setpin()-call resp. par clrpin()-call, then
* - SCK is high for 2T
* - SCK is low for 2T
* - MOSI setuptime is 1T
* - MOSI holdtime is 3T
* - SCK low to MISO read is 2T to 3T
* So we are within programming specs (expect for AT90S1200),
* if and only if T>t_CLCL (t_CLCL=clock period of target system).
*
* Due to the delay introduced by "IN" and "OUT"-commands,
* T is greater than 1us (more like 2us) on x86-architectures.
* So programming works safely down to 1MHz target clock.
*/
b = (byte >> i) & 0x01;
/* set the data input line as desired */
bitbang_setpin(pgm, pgm->pinno[PIN_AVR_MOSI], b);
bitbang_setpin(pgm, pgm->pinno[PIN_AVR_SCK], 1);
/*
* read the result bit (it is either valid from a previous falling
* edge or it is ignored in the current context)
*/
r = bitbang_getpin(pgm, pgm->pinno[PIN_AVR_MISO]);
bitbang_setpin(pgm, pgm->pinno[PIN_AVR_SCK], 0);
rbyte |= r << i;
}
return rbyte;
}
int bitbang_rdy_led(PROGRAMMER * pgm, int value)
{
bitbang_setpin(pgm, pgm->pinno[PIN_LED_RDY], !value);
return 0;
}
int bitbang_err_led(PROGRAMMER * pgm, int value)
{
bitbang_setpin(pgm, pgm->pinno[PIN_LED_ERR], !value);
return 0;
}
int bitbang_pgm_led(PROGRAMMER * pgm, int value)
{
bitbang_setpin(pgm, pgm->pinno[PIN_LED_PGM], !value);
return 0;
}
int bitbang_vfy_led(PROGRAMMER * pgm, int value)
{
bitbang_setpin(pgm, pgm->pinno[PIN_LED_VFY], !value);
return 0;
}
/*
* transmit an AVR device command and return the results; 'cmd' and
* 'res' must point to at least a 4 byte data buffer
*/
int bitbang_cmd(PROGRAMMER * pgm, unsigned char cmd[4],
unsigned char res[4])
{
int i;
for (i=0; i<4; i++) {
res[i] = bitbang_txrx(pgm, cmd[i]);
}
if(verbose >= 2)
{
fprintf(stderr, "bitbang_cmd(): [ ");
for(i = 0; i < 4; i++)
fprintf(stderr, "%02X ", cmd[i]);
fprintf(stderr, "] [ ");
for(i = 0; i < 4; i++)
{
fprintf(stderr, "%02X ", res[i]);
}
fprintf(stderr, "]\n");
}
return 0;
}
/*
* issue the 'chip erase' command to the AVR device
*/
int bitbang_chip_erase(PROGRAMMER * pgm, AVRPART * p)
{
unsigned char cmd[4];
unsigned char res[4];
if (p->op[AVR_OP_CHIP_ERASE] == NULL) {
fprintf(stderr, "chip erase instruction not defined for part \"%s\"\n",
p->desc);
return -1;
}
pgm->pgm_led(pgm, ON);
memset(cmd, 0, sizeof(cmd));
avr_set_bits(p->op[AVR_OP_CHIP_ERASE], cmd);
pgm->cmd(pgm, cmd, res);
usleep(p->chip_erase_delay);
pgm->initialize(pgm, p);
pgm->pgm_led(pgm, OFF);
return 0;
}
/*
* issue the 'program enable' command to the AVR device
*/
int bitbang_program_enable(PROGRAMMER * pgm, AVRPART * p)
{
unsigned char cmd[4];
unsigned char res[4];
if (p->op[AVR_OP_PGM_ENABLE] == NULL) {
fprintf(stderr, "program enable instruction not defined for part \"%s\"\n",
p->desc);
return -1;
}
memset(cmd, 0, sizeof(cmd));
avr_set_bits(p->op[AVR_OP_PGM_ENABLE], cmd);
pgm->cmd(pgm, cmd, res);
if (res[2] != cmd[1])
return -2;
return 0;
}
/*
* initialize the AVR device and prepare it to accept commands
*/
int bitbang_initialize(PROGRAMMER * pgm, AVRPART * p)
{
int rc;
int tries;
pgm->powerup(pgm);
usleep(20000);
bitbang_setpin(pgm, pgm->pinno[PIN_AVR_SCK], 0);
bitbang_setpin(pgm, pgm->pinno[PIN_AVR_RESET], 0);
usleep(20000);
bitbang_highpulsepin(pgm, pgm->pinno[PIN_AVR_RESET]);
usleep(20000); /* 20 ms XXX should be a per-chip parameter */
/*
* Enable programming mode. If we are programming an AT90S1200, we
* can only issue the command and hope it worked. If we are using
* one of the other chips, the chip will echo 0x53 when issuing the
* third byte of the command. In this case, try up to 32 times in
* order to possibly get back into sync with the chip if we are out
* of sync.
*/
if (strcmp(p->desc, "AT90S1200")==0) {
pgm->program_enable(pgm, p);
}
else {
tries = 0;
do {
rc = pgm->program_enable(pgm, p);
if ((rc == 0)||(rc == -1))
break;
bitbang_highpulsepin(pgm, pgm->pinno[p->retry_pulse/*PIN_AVR_SCK*/]);
tries++;
} while (tries < 65);
/*
* can't sync with the device, maybe it's not attached?
*/
if (rc) {
fprintf(stderr, "%s: AVR device not responding\n", progname);
return -1;
}
}
return 0;
}