avrdude/stk500.c

1013 lines
21 KiB
C

/*
* avrdude - A Downloader/Uploader for AVR device programmers
* Copyright (C) 2002, 2003 Brian S. Dean <bsd@bsdhome.com>
*
* 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
*/
/* $Id$ */
/*
* avrdude interface for Atmel STK500 programmer
*
* Note: most commands use the "universal command" feature of the
* programmer in a "pass through" mode, exceptions are "program
* enable", "paged read", and "paged write".
*
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <fcntl.h>
#include <unistd.h>
#include <errno.h>
#include <termios.h>
#include <sys/time.h>
#include "avr.h"
#include "pgm.h"
#include "stk500_private.h"
extern char * progname;
extern int do_cycles;
static int stk500_send(PROGRAMMER * pgm, char * buf, int buflen)
{
struct timeval timeout;
fd_set wfds;
int nfds;
int rc;
if (!buflen)
return 0;
timeout.tv_sec = 0;
timeout.tv_usec = 500000;
while (buflen) {
FD_ZERO(&wfds);
FD_SET(pgm->fd, &wfds);
reselect:
nfds = select(pgm->fd+1, NULL, &wfds, NULL, &timeout);
if (nfds == 0) {
fprintf(stderr,
"%s: stk500_send(): programmer is not responding on %s\n",
progname, pgm->port);
exit(1);
}
else if (nfds == -1) {
if (errno == EINTR) {
goto reselect;
}
else {
fprintf(stderr, "%s: stk500_send(): select(): %s\n",
progname, strerror(errno));
exit(1);
}
}
rc = write(pgm->fd, buf, 1);
if (rc < 0) {
fprintf(stderr, "%s: stk500_send(): write error: %s\n",
progname, strerror(errno));
exit(1);
}
buf++;
buflen--;
}
return 0;
}
static int stk500_recv(PROGRAMMER * pgm, char * buf, int n)
{
struct timeval timeout;
fd_set rfds;
int nfds;
int rc;
timeout.tv_sec = 0;
timeout.tv_usec = 500000;
while (n) {
FD_ZERO(&rfds);
FD_SET(pgm->fd, &rfds);
reselect:
nfds = select(pgm->fd+1, &rfds, NULL, NULL, &timeout);
if (nfds == 0) {
fprintf(stderr,
"%s: stk500_recv(): programmer is not responding on %s\n",
progname, pgm->port);
exit(1);
}
else if (nfds == -1) {
if (errno == EINTR) {
goto reselect;
}
else {
fprintf(stderr, "%s: stk500_recv(): select(): %s\n",
progname, strerror(errno));
exit(1);
}
}
rc = read(pgm->fd, buf, 1);
if (rc < 0) {
fprintf(stderr, "%s: stk500_recv(): read error: %s\n",
progname, strerror(errno));
exit(1);
}
buf++;
n--;
}
return 0;
}
static int stk500_drain(PROGRAMMER * pgm, int display)
{
struct timeval timeout;
fd_set rfds;
int nfds;
int rc;
unsigned char buf;
timeout.tv_sec = 0;
timeout.tv_usec = 250000;
if (display) {
fprintf(stderr, "drain>");
}
while (1) {
FD_ZERO(&rfds);
FD_SET(pgm->fd, &rfds);
reselect:
nfds = select(pgm->fd+1, &rfds, NULL, NULL, &timeout);
if (nfds == 0) {
if (display) {
fprintf(stderr, "<drain\n");
}
return 0;
}
else if (nfds == -1) {
if (errno == EINTR) {
goto reselect;
}
else {
fprintf(stderr, "%s: stk500_drain(): select(): %s\n",
progname, strerror(errno));
exit(1);
}
}
rc = read(pgm->fd, &buf, 1);
if (rc < 0) {
fprintf(stderr, "%s: stk500_drain(): read error: %s\n",
progname, strerror(errno));
exit(1);
}
if (display) {
fprintf(stderr, "%02x ", buf);
}
}
}
static int stk500_getsync(PROGRAMMER * pgm)
{
unsigned char buf[32], resp[32];
/*
* get in sync */
buf[0] = Cmnd_STK_GET_SYNC;
buf[1] = Sync_CRC_EOP;
stk500_send(pgm, buf, 2);
stk500_recv(pgm, resp, 1);
if (resp[0] != Resp_STK_INSYNC) {
fprintf(stderr,
"%s: stk500_getsync(): not in sync: resp=0x%02x\n",
progname, resp[0]);
stk500_drain(pgm, 0);
exit(1);
}
stk500_recv(pgm, resp, 1);
if (resp[0] != Resp_STK_OK) {
fprintf(stderr,
"%s: stk500_getsync(): can't communicate with device: "
"resp=0x%02x\n",
progname, resp[0]);
exit(1);
}
return 0;
}
static int stk500_rdy_led(PROGRAMMER * pgm, int value)
{
return 0;
}
static int stk500_err_led(PROGRAMMER * pgm, int value)
{
return 0;
}
static int stk500_pgm_led(PROGRAMMER * pgm, int value)
{
return 0;
}
static int stk500_vfy_led(PROGRAMMER * pgm, int 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
*/
static int stk500_cmd(PROGRAMMER * pgm, unsigned char cmd[4],
unsigned char res[4])
{
unsigned char buf[32];
buf[0] = Cmnd_STK_UNIVERSAL;
buf[1] = cmd[0];
buf[2] = cmd[1];
buf[3] = cmd[2];
buf[4] = cmd[3];
buf[5] = Sync_CRC_EOP;
stk500_send(pgm, buf, 6);
stk500_recv(pgm, buf, 1);
if (buf[0] != Resp_STK_INSYNC) {
fprintf(stderr, "%s: stk500_cmd(): programmer is out of sync\n", progname);
exit(1);
}
res[0] = cmd[1];
res[1] = cmd[2];
res[2] = cmd[3];
stk500_recv(pgm, &res[3], 1);
stk500_recv(pgm, buf, 1);
if (buf[0] != Resp_STK_OK) {
fprintf(stderr, "%s: stk500_cmd(): protocol error\n", progname);
exit(1);
}
return 0;
}
/*
* issue the 'chip erase' command to the AVR device
*/
static int stk500_chip_erase(PROGRAMMER * pgm, AVRPART * p)
{
unsigned char cmd[4];
unsigned char res[4];
int cycles;
int rc;
if (p->op[AVR_OP_CHIP_ERASE] == NULL) {
fprintf(stderr, "chip erase instruction not defined for part \"%s\"\n",
p->desc);
return -1;
}
rc = avr_get_cycle_count(pgm, p, &cycles);
/*
* only print out the current cycle count if we aren't going to
* display it below
*/
if (!do_cycles && ((rc >= 0) && (cycles != 0xffffffff))) {
fprintf(stderr,
"%s: current erase-rewrite cycle count is %d%s\n",
progname, cycles,
do_cycles ? "" : " (if being tracked)");
}
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);
if (do_cycles && (cycles != -1)) {
if (cycles == 0x00ffff) {
cycles = 0;
}
cycles++;
fprintf(stderr, "%s: erase-rewrite cycle count is now %d\n",
progname, cycles);
avr_put_cycle_count(pgm, p, cycles);
}
return 0;
}
/*
* issue the 'program enable' command to the AVR device
*/
static int stk500_program_enable(PROGRAMMER * pgm, AVRPART * p)
{
unsigned char buf[16];
int tries=0;
retry:
tries++;
buf[0] = Cmnd_STK_ENTER_PROGMODE;
buf[1] = Sync_CRC_EOP;
stk500_send(pgm, buf, 2);
stk500_recv(pgm, buf, 1);
if (buf[0] == Resp_STK_NOSYNC) {
if (tries > 33) {
fprintf(stderr, "%s: stk500_program_enable(): can't get into sync\n",
progname);
return -1;
}
stk500_getsync(pgm);
goto retry;
}
else if (buf[0] != Resp_STK_INSYNC) {
fprintf(stderr,
"%s: stk500_program_enable(): protocol error, "
"expect=0x%02x, resp=0x%02x\n",
progname, Resp_STK_INSYNC, buf[0]);
return -1;
}
stk500_recv(pgm, buf, 1);
if (buf[0] == Resp_STK_OK) {
return 0;
}
else if (buf[0] == Resp_STK_NODEVICE) {
fprintf(stderr, "%s: stk500_program_enable(): no device\n",
progname);
return -1;
}
fprintf(stderr, "%s: stk500_program_enamble(): unkown response=0x%02x\n",
progname, buf[0]);
return -1;
}
/*
* apply power to the AVR processor
*/
static void stk500_powerup(PROGRAMMER * pgm)
{
return;
}
/*
* remove power from the AVR processor
*/
static void stk500_powerdown(PROGRAMMER * pgm)
{
return;
}
/*
* initialize the AVR device and prepare it to accept commands
*/
static int stk500_initialize(PROGRAMMER * pgm, AVRPART * p)
{
unsigned char buf[32];
AVRMEM * m;
int tries;
tries = 0;
retry:
tries++;
/*
* set device programming parameters
*/
buf[0] = Cmnd_STK_SET_DEVICE;
buf[1] = p->devicecode;
buf[2] = 0; /* device revision */
buf[3] = 0; /* parallel and serial programming */
buf[4] = 1; /* full parallel interface */
buf[5] = 1; /* polling supported - XXX need this in config file */
buf[6] = 1; /* programming is self-timed - XXX need in config file */
m = avr_locate_mem(p, "lock");
if (m)
buf[7] = m->size;
else
buf[7] = 0;
/*
* number of fuse bytes
*/
buf[8] = 0;
m = avr_locate_mem(p, "fuse");
if (m)
buf[8] += m->size;
m = avr_locate_mem(p, "lfuse");
if (m)
buf[8] += m->size;
m = avr_locate_mem(p, "hfuse");
if (m)
buf[8] += m->size;
m = avr_locate_mem(p, "efuse");
if (m)
buf[8] += m->size;
m = avr_locate_mem(p, "flash");
if (m) {
buf[9] = m->readback[0];
buf[10] = m->readback[1];
if (m->paged) {
buf[13] = (m->page_size >> 8) & 0x00ff;
buf[14] = m->page_size & 0x00ff;
}
buf[17] = (m->size >> 24) & 0xff;
buf[18] = (m->size >> 16) & 0xff;
buf[19] = (m->size >> 8) & 0xff;
buf[20] = m->size & 0xff;
}
else {
buf[9] = 0xff;
buf[10] = 0xff;
buf[13] = 0;
buf[14] = 0;
buf[17] = 0;
buf[18] = 0;
buf[19] = 0;
buf[20] = 0;
}
m = avr_locate_mem(p, "eeprom");
if (m) {
buf[11] = m->readback[0];
buf[12] = m->readback[1];
buf[15] = (m->size >> 8) & 0x00ff;
buf[16] = m->size & 0x00ff;
}
else {
buf[11] = 0xff;
buf[12] = 0xff;
buf[15] = 0;
buf[16] = 0;
}
buf[21] = Sync_CRC_EOP;
stk500_send(pgm, buf, 22);
stk500_recv(pgm, buf, 1);
if (buf[0] == Resp_STK_NOSYNC) {
fprintf(stderr,
"%s: stk500_initialize(): programmer not in sync, resp=0x%02x\n",
progname, buf[0]);
if (tries > 33)
return -1;
stk500_getsync(pgm);
goto retry;
return -1;
}
else if (buf[0] != Resp_STK_INSYNC) {
fprintf(stderr,
"%s: stk500_initialize(): (a) protocol error, "
"expect=0x%02x, resp=0x%02x\n",
progname, Resp_STK_INSYNC, buf[0]);
return -1;
}
stk500_recv(pgm, buf, 1);
if (buf[0] != Resp_STK_OK) {
fprintf(stderr,
"%s: stk500_initialize(): (b) protocol error, "
"expect=0x%02x, resp=0x%02x\n",
progname, Resp_STK_OK, buf[0]);
return -1;
}
return pgm->program_enable(pgm, p);
}
static int stk500_save(PROGRAMMER * pgm)
{
return 0;
}
static void stk500_restore(PROGRAMMER * pgm)
{
return;
}
static void stk500_disable(PROGRAMMER * pgm)
{
unsigned char buf[16];
int tries=0;
retry:
tries++;
buf[0] = Cmnd_STK_LEAVE_PROGMODE;
buf[1] = Sync_CRC_EOP;
stk500_send(pgm, buf, 2);
stk500_recv(pgm, buf, 1);
if (buf[0] == Resp_STK_NOSYNC) {
if (tries > 33) {
fprintf(stderr, "%s: stk500_program_enable(): can't get into sync\n",
progname);
return;
}
stk500_getsync(pgm);
goto retry;
}
else if (buf[0] != Resp_STK_INSYNC) {
fprintf(stderr,
"%s: stk500_initialize(): (a) protocol error, "
"expect=0x%02x, resp=0x%02x\n",
progname, Resp_STK_INSYNC, buf[0]);
return;
}
stk500_recv(pgm, buf, 1);
if (buf[0] == Resp_STK_OK) {
return;
}
else if (buf[0] == Resp_STK_NODEVICE) {
fprintf(stderr, "%s: stk500_program_enable(): no device\n",
progname);
return;
}
fprintf(stderr, "%s: stk500_program_enamble(): unkown response=0x%02x\n",
progname, buf[0]);
return;
}
static void stk500_enable(PROGRAMMER * pgm)
{
return;
}
static int stk500_setattr(int fd)
{
int rc;
struct termios termios;
if (!isatty(fd))
return -1;
/*
* initialize terminal modes
*/
rc = tcgetattr(fd, &termios);
if (rc < 0) {
fprintf(stderr, "%s: stk500_setattr(): tcgetattr() failed, %s",
progname, strerror(errno));
return -errno;
}
termios.c_iflag = 0;
termios.c_oflag = 0;
termios.c_cflag &= ~ (PARENB | CSIZE | CSTOPB);
termios.c_cflag |= (CS8 | CREAD | CLOCAL);
termios.c_lflag = 0;
termios.c_cc[VMIN] = 1;
termios.c_cc[VTIME] = 0;
cfsetospeed(&termios, B115200);
cfsetispeed(&termios, B115200);
rc = tcsetattr(fd, TCSANOW, &termios);
if (rc < 0) {
fprintf(stderr, "%s: stk500_setattr(): tcsetattr() failed, %s",
progname, strerror(errno));
return -errno;
}
return 0;
}
static void stk500_open(PROGRAMMER * pgm, char * port)
{
int rc;
strcpy(pgm->port, port);
/*
* open the serial port
*/
pgm->fd = open(port, O_RDWR | O_NOCTTY /*| O_NONBLOCK*/);
if (pgm->fd < 0) {
fprintf(stderr, "%s: stk500_open(): can't open device \"%s\": %s\n",
progname, port, strerror(errno));
exit(1);
}
/*
* set serial line attributes
*/
rc = stk500_setattr(pgm->fd);
if (rc) {
fprintf(stderr,
"%s: stk500_open(): can't set attributes for device \"%s\"\n",
progname, port);
exit(1);
}
/*
* drain any extraneous input
*/
stk500_drain(pgm, 0);
stk500_getsync(pgm);
stk500_drain(pgm, 0);
}
static void stk500_close(PROGRAMMER * pgm)
{
close(pgm->fd);
pgm->fd = -1;
}
static int stk500_loadaddr(PROGRAMMER * pgm, unsigned int addr)
{
unsigned char buf[16];
int tries;
tries = 0;
retry:
tries++;
buf[0] = Cmnd_STK_LOAD_ADDRESS;
buf[1] = addr & 0xff;
buf[2] = (addr >> 8) & 0xff;
buf[3] = Sync_CRC_EOP;
stk500_send(pgm, buf, 4);
stk500_recv(pgm, buf, 1);
if (buf[0] == Resp_STK_NOSYNC) {
if (tries > 33) {
fprintf(stderr, "%s: stk500_loadaddr(): can't get into sync\n",
progname);
return -1;
}
stk500_getsync(pgm);
goto retry;
}
else if (buf[0] != Resp_STK_INSYNC) {
fprintf(stderr,
"%s: stk500_loadaddr(): (a) protocol error, "
"expect=0x%02x, resp=0x%02x\n",
progname, Resp_STK_INSYNC, buf[0]);
return -1;
}
stk500_recv(pgm, buf, 1);
if (buf[0] == Resp_STK_OK) {
return 0;
}
fprintf(stderr,
"%s: loadaddr(): (b) protocol error, "
"expect=0x%02x, resp=0x%02x\n",
progname, Resp_STK_INSYNC, buf[0]);
return -1;
}
static int stk500_paged_write(PROGRAMMER * pgm, AVRPART * p, AVRMEM * m,
int page_size, int n_bytes)
{
unsigned char buf[16];
int memtype;
unsigned int addr;
int a_div;
int i;
int tries;
unsigned int n;
if (strcmp(m->desc, "flash") == 0) {
memtype = 'F';
}
else if (strcmp(m->desc, "eeprom") == 0) {
memtype = 'E';
}
else {
return -2;
}
if ((m->op[AVR_OP_LOADPAGE_LO]) || (m->op[AVR_OP_READ_LO]))
a_div = 2;
else
a_div = 1;
if (n_bytes > m->size) {
n_bytes = m->size;
n = m->size;
}
else {
if ((n_bytes % page_size) != 0) {
n = n_bytes + page_size - (n_bytes % page_size);
}
else {
n = n_bytes;
}
}
for (addr = 0; addr < n; addr += page_size) {
fprintf(stderr, "\r \r%6u", addr);
tries = 0;
retry:
tries++;
stk500_loadaddr(pgm, addr/a_div);
buf[0] = Cmnd_STK_PROG_PAGE;
buf[1] = (page_size >> 8) & 0xff;
buf[2] = page_size & 0xff;
buf[3] = memtype;
stk500_send(pgm, buf, 4);
for (i=0; i<page_size; i++) {
buf[0] = m->buf[addr + i];
stk500_send(pgm, buf, 1);
}
buf[0] = Sync_CRC_EOP;
stk500_send(pgm, buf, 1);
stk500_recv(pgm, buf, 1);
if (buf[0] == Resp_STK_NOSYNC) {
if (tries > 33) {
fprintf(stderr, "\n%s: stk500_paged_write(): can't get into sync\n",
progname);
return -3;
}
stk500_getsync(pgm);
goto retry;
}
else if (buf[0] != Resp_STK_INSYNC) {
fprintf(stderr,
"\n%s: stk500_paged_write(): (a) protocol error, "
"expect=0x%02x, resp=0x%02x\n",
progname, Resp_STK_INSYNC, buf[0]);
return -4;
}
stk500_recv(pgm, buf, 1);
if (buf[0] != Resp_STK_OK) {
fprintf(stderr,
"\n%s: stk500_paged_write(): (a) protocol error, "
"expect=0x%02x, resp=0x%02x\n",
progname, Resp_STK_INSYNC, buf[0]);
return -5;
}
}
fprintf(stderr, "\r \r%6u", addr-1);
fprintf(stderr, "\n");
return n;
}
static int stk500_paged_load(PROGRAMMER * pgm, AVRPART * p, AVRMEM * m,
int page_size, int n_bytes)
{
unsigned char buf[16];
int memtype;
unsigned int addr;
int a_div;
int tries;
unsigned int n;
if (strcmp(m->desc, "flash") == 0) {
memtype = 'F';
}
else if (strcmp(m->desc, "eeprom") == 0) {
memtype = 'E';
}
else {
return -2;
}
if ((m->op[AVR_OP_LOADPAGE_LO]) || (m->op[AVR_OP_READ_LO]))
a_div = 2;
else
a_div = 1;
if (n_bytes > m->size) {
n_bytes = m->size;
n = m->size;
}
else {
if ((n_bytes % page_size) != 0) {
n = n_bytes + page_size - (n_bytes % page_size);
}
else {
n = n_bytes;
}
}
for (addr = 0; addr < n; addr += page_size) {
fprintf(stderr, "\r \r%6u", addr);
tries = 0;
retry:
tries++;
stk500_loadaddr(pgm, addr/a_div);
buf[0] = Cmnd_STK_READ_PAGE;
buf[1] = (page_size >> 8) & 0xff;
buf[2] = page_size & 0xff;
buf[3] = memtype;
buf[4] = Sync_CRC_EOP;
stk500_send(pgm, buf, 5);
stk500_recv(pgm, buf, 1);
if (buf[0] == Resp_STK_NOSYNC) {
if (tries > 33) {
fprintf(stderr, "\n%s: stk500_paged_load(): can't get into sync\n",
progname);
return -3;
}
stk500_getsync(pgm);
goto retry;
}
else if (buf[0] != Resp_STK_INSYNC) {
fprintf(stderr,
"\n%s: stk500_paged_load(): (a) protocol error, "
"expect=0x%02x, resp=0x%02x\n",
progname, Resp_STK_INSYNC, buf[0]);
return -4;
}
stk500_recv(pgm, &m->buf[addr], page_size);
stk500_recv(pgm, buf, 1);
if (buf[0] != Resp_STK_OK) {
fprintf(stderr,
"\n%s: stk500_paged_load(): (a) protocol error, "
"expect=0x%02x, resp=0x%02x\n",
progname, Resp_STK_INSYNC, buf[0]);
return -5;
}
}
fprintf(stderr, "\r \r%6u", addr-1);
fprintf(stderr, "\n");
return n;
}
static int stk500_getparm(PROGRAMMER * pgm, unsigned parm, unsigned * value)
{
unsigned char buf[16];
unsigned v;
int tries = 0;
retry:
tries++;
buf[0] = Cmnd_STK_GET_PARAMETER;
buf[1] = parm;
buf[2] = Sync_CRC_EOP;
stk500_send(pgm, buf, 3);
stk500_recv(pgm, buf, 1);
if (buf[0] == Resp_STK_NOSYNC) {
if (tries > 33) {
fprintf(stderr, "\n%s: getparm(): can't get into sync\n",
progname);
return -1;
}
stk500_getsync(pgm);
goto retry;
}
else if (buf[0] != Resp_STK_INSYNC) {
fprintf(stderr,
"\n%s: getparm(): (a) protocol error, "
"expect=0x%02x, resp=0x%02x\n",
progname, Resp_STK_INSYNC, buf[0]);
return -2;
}
stk500_recv(pgm, buf, 1);
v = buf[0];
stk500_recv(pgm, buf, 1);
if (buf[0] == Resp_STK_FAILED) {
fprintf(stderr,
"\n%s: getparm(): parameter 0x%02x failed\n",
progname, v);
return -3;
}
else if (buf[0] != Resp_STK_OK) {
fprintf(stderr,
"\n%s: getparm(): (a) protocol error, "
"expect=0x%02x, resp=0x%02x\n",
progname, Resp_STK_INSYNC, buf[0]);
return -3;
}
*value = v;
return 0;
}
static void stk500_display(PROGRAMMER * pgm, char * p)
{
unsigned maj, min, hdw;
stk500_getparm(pgm, Parm_STK_HW_VER, &hdw);
stk500_getparm(pgm, Parm_STK_SW_MAJOR, &maj);
stk500_getparm(pgm, Parm_STK_SW_MINOR, &min);
fprintf(stderr, "%sHardware Version: %d\n", p, hdw);
fprintf(stderr, "%sFirmware Version: %d.%d\n", p, maj, min);
return;
}
void stk500_initpgm(PROGRAMMER * pgm)
{
strcpy(pgm->type, "STK500");
/*
* mandatory functions
*/
pgm->rdy_led = stk500_rdy_led;
pgm->err_led = stk500_err_led;
pgm->pgm_led = stk500_pgm_led;
pgm->vfy_led = stk500_vfy_led;
pgm->initialize = stk500_initialize;
pgm->display = stk500_display;
pgm->save = stk500_save;
pgm->restore = stk500_restore;
pgm->enable = stk500_enable;
pgm->disable = stk500_disable;
pgm->powerup = stk500_powerup;
pgm->powerdown = stk500_powerdown;
pgm->program_enable = stk500_program_enable;
pgm->chip_erase = stk500_chip_erase;
pgm->cmd = stk500_cmd;
pgm->open = stk500_open;
pgm->close = stk500_close;
/*
* optional functions
*/
pgm->paged_write = stk500_paged_write;
pgm->paged_load = stk500_paged_load;
pgm->page_size = 256;
}