jtag: basic support for P&E Micro OSBDM (aka OSJTAG) adapter

This driver provides support for the P&E Micro OSBDM adapter (sometimes
named as OSJTAG), mounted on the Freescale TWRK60N512 bord. Thus, it
provides a quick start when working with this board. The driver doesn't
use BDM commands, but work with OSBDM adapter using only JTAG commands.

Change-Id: Ibc3779538e666e07651d3136431e5d44344f3b07
Signed-off-by: Jan Dakinevich <jan.dakinevich@gmail.com>
Reviewed-on: http://openocd.zylin.com/492
Tested-by: jenkins
Reviewed-by: Tomas Frydrych <tf+openocd@r-finger.com>
Reviewed-by: Spencer Oliver <spen@spen-soft.co.uk>
This commit is contained in:
Jan Dakinevich 2012-02-28 00:51:12 +04:00 committed by Spencer Oliver
parent 736e8bb773
commit 34d1f82c75
6 changed files with 759 additions and 3 deletions

View File

@ -478,6 +478,10 @@ AC_ARG_ENABLE([stlink],
AS_HELP_STRING([--enable-stlink], [Enable building support for the ST-Link JTAG Programmer]),
[build_stlink=$enableval], [build_stlink=no])
AC_ARG_ENABLE([osbdm],
AS_HELP_STRING([--enable-osbdm], [Enable building support for the OSBDM (JTAG only) Programmer]),
[build_osbdm=$enableval], [build_osbdm=no])
AC_ARG_ENABLE([minidriver_dummy],
AS_HELP_STRING([--enable-minidriver-dummy], [Enable the dummy minidriver.]),
[build_minidriver_dummy=$enableval], [build_minidriver_dummy=no])
@ -783,6 +787,12 @@ else
AC_DEFINE(BUILD_STLINK, 0, [0 if you don't want the ST-Link JTAG driver.])
fi
if test $build_osbdm = yes; then
AC_DEFINE(BUILD_OSBDM, 1, [1 if you want the OSBDM driver.])
else
AC_DEFINE(BUILD_OSBDM, 0, [0 if you don't want the OSBDM driver.])
fi
if test "$use_internal_jimtcl" = yes; then
if test -f "$srcdir/jimtcl/configure.ac"; then
AX_CONFIG_SUBDIR_OPTION([jimtcl], [--disable-install-jim])
@ -1069,7 +1079,7 @@ fi
# Check for libusb1 ported drivers.
build_usb_ng=no
if test $build_jlink = yes -o $build_stlink = yes; then
if test $build_jlink = yes -o $build_stlink = yes -o $build_osbdm = yes; then
build_usb_ng=yes
fi
@ -1118,6 +1128,7 @@ AM_CONDITIONAL([ARMJTAGEW], [test $build_armjtagew = yes])
AM_CONDITIONAL([REMOTE_BITBANG], [test $build_remote_bitbang = yes])
AM_CONDITIONAL([BUSPIRATE], [test $build_buspirate = yes])
AM_CONDITIONAL([STLINK], [test $build_stlink = yes])
AM_CONDITIONAL([OSBDM], [test $build_osbdm = yes])
AM_CONDITIONAL([USB], [test $build_usb = yes])
AM_CONDITIONAL([USB_NG], [test $build_usb_ng = yes])
AM_CONDITIONAL([USE_LIBUSB0], [test $use_libusb0 = yes])

View File

@ -98,6 +98,9 @@ endif
if STLINK
DRIVERFILES += stlink_usb.c
endif
if OSBDM
DRIVERFILES += osbdm.c
endif
noinst_HEADERS = \
bitbang.h \

722
src/jtag/drivers/osbdm.c Normal file
View File

@ -0,0 +1,722 @@
/***************************************************************************
* Copyright (C) 2012 by Jan Dakinevich *
* jan.dakinevich@gmail.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. *
***************************************************************************/
#ifdef HAVE_CONFIG_H
# include "config.h"
#endif
#include <helper/log.h>
#include <helper/binarybuffer.h>
#include <helper/command.h>
#include <jtag/interface.h>
#include "libusb_common.h"
struct sequence {
int len;
void *tms;
void *tdo;
const void *tdi;
struct sequence *next;
};
struct queue {
struct sequence *head;
struct sequence *tail;
};
static struct sequence *queue_add_tail(struct queue *queue, int len)
{
if (len <= 0) {
LOG_ERROR("BUG: sequences with zero length are not allowed");
return NULL;
}
struct sequence *next;
next = (struct sequence *)malloc(sizeof(*next));
if (next) {
next->tms = calloc(1, DIV_ROUND_UP(len, 8));
if (next->tms) {
next->len = len;
next->tdo = NULL;
next->tdi = NULL;
next->next = NULL;
if (!queue->head) {
/* Queue is empty at the moment */
queue->head = next;
} else {
/* Queue already contains at least one sequence */
queue->tail->next = next;
}
queue->tail = next;
} else {
free(next);
next = NULL;
}
}
if (!next)
LOG_ERROR("Not enough memory");
return next;
}
static void queue_drop_head(struct queue *queue)
{
struct sequence *head = queue->head->next; /* New head */
free(queue->head->tms);
free(queue->head);
queue->head = head;
}
static void queue_free(struct queue *queue)
{
if (queue) {
while (queue->head)
queue_drop_head(queue);
free(queue);
}
}
static struct queue *queue_alloc(void)
{
struct queue *queue = (struct queue *)malloc(sizeof(struct queue));
if (queue)
queue->head = NULL;
else
LOG_ERROR("Not enough memory");
return queue;
}
/* Size of usb communnication buffer */
#define OSBDM_USB_BUFSIZE 64
/* Timeout for USB transfer, ms */
#define OSBDM_USB_TIMEOUT 1000
/* Write end point */
#define OSBDM_USB_EP_WRITE 0x01
/* Read end point */
#define OSBDM_USB_EP_READ 0x82
/* Initialize OSBDM device */
#define OSBDM_CMD_INIT 0x11
/* Execute special, not-BDM command. But only this
* command is used for JTAG operation */
#define OSBDM_CMD_SPECIAL 0x27
/* Execute JTAG swap (tms/tdi -> tdo) */
#define OSBDM_CMD_SPECIAL_SWAP 0x05
/* Reset control */
#define OSBDM_CMD_SPECIAL_SRST 0x01
/* Maximum bit-length in one swap */
#define OSBDM_SWAP_MAX (((OSBDM_USB_BUFSIZE - 6) / 5) * 16)
/* Lists of valid VID/PID pairs
*/
static const uint16_t osbdm_vid[] = { 0x15a2, 0x15a2, 0 };
static const uint16_t osbdm_pid[] = { 0x0042, 0x0058, 0 };
struct osbdm {
struct jtag_libusb_device_handle *devh; /* USB handle */
uint8_t buffer[OSBDM_USB_BUFSIZE]; /* Data to send and recieved */
int count; /* Count data to send and to read */
};
/* osbdm instance
*/
static struct osbdm osbdm_context;
static int osbdm_send_and_recv(struct osbdm *osbdm)
{
/* Send request */
int count = jtag_libusb_bulk_write(osbdm->devh, OSBDM_USB_EP_WRITE,
(char *)osbdm->buffer, osbdm->count, OSBDM_USB_TIMEOUT);
if (count != osbdm->count) {
LOG_ERROR("OSBDM communnication error: can't write");
return ERROR_FAIL;
}
/* Save command code for next checking */
uint8_t cmd_saved = osbdm->buffer[0];
/* Reading answer */
osbdm->count = jtag_libusb_bulk_read(osbdm->devh, OSBDM_USB_EP_READ,
(char *)osbdm->buffer, OSBDM_USB_BUFSIZE, OSBDM_USB_TIMEOUT);
/* Now perform basic checks for data sent by BDM device
*/
if (osbdm->count < 0) {
LOG_ERROR("OSBDM communnication error: can't read");
return ERROR_FAIL;
}
if (osbdm->count < 2) {
LOG_ERROR("OSBDM communnication error: answer too small");
return ERROR_FAIL;
}
if (osbdm->count != osbdm->buffer[1]) {
LOG_ERROR("OSBDM communnication error: answer size mismatch");
return ERROR_FAIL;
}
if (cmd_saved != osbdm->buffer[0]) {
LOG_ERROR("OSBDM communnication error: answer command mismatch");
return ERROR_FAIL;
}
return ERROR_OK;
}
static int osbdm_srst(struct osbdm *osbdm, int srst)
{
osbdm->count = 0;
(void)memset(osbdm->buffer, 0, OSBDM_USB_BUFSIZE);
/* Composing request
*/
osbdm->buffer[osbdm->count++] = OSBDM_CMD_SPECIAL; /* Command */
osbdm->buffer[osbdm->count++] = OSBDM_CMD_SPECIAL_SRST; /* Subcommand */
/* Length in bytes - not used */
osbdm->buffer[osbdm->count++] = 0;
osbdm->buffer[osbdm->count++] = 0;
/* SRST state */
osbdm->buffer[osbdm->count++] = (srst ? 0 : 0x08);
/* Sending data
*/
if (osbdm_send_and_recv(osbdm) != ERROR_OK)
return ERROR_FAIL;
return ERROR_OK;
}
static int osbdm_swap(struct osbdm *osbdm, void *tms, void *tdi,
void *tdo, int length)
{
if (length > OSBDM_SWAP_MAX) {
LOG_ERROR("BUG: bit sequence too long");
return ERROR_FAIL;
}
if (length <= 0) {
LOG_ERROR("BUG: bit sequence equal or less to 0");
return ERROR_FAIL;
}
int swap_count = DIV_ROUND_UP(length, 16);
/* cleanup */
osbdm->count = 0;
(void)memset(osbdm->buffer, 0, OSBDM_USB_BUFSIZE);
/* Composing request
*/
osbdm->buffer[osbdm->count++] = OSBDM_CMD_SPECIAL; /* Command */
osbdm->buffer[osbdm->count++] = OSBDM_CMD_SPECIAL_SWAP; /* Subcommand */
/* Length in bytes - not used */
osbdm->buffer[osbdm->count++] = 0;
osbdm->buffer[osbdm->count++] = 0;
/* Swap count */
osbdm->buffer[osbdm->count++] = 0;
osbdm->buffer[osbdm->count++] = (uint8_t)swap_count;
for (int bit_idx = 0; bit_idx < length; ) {
/* Bit count in swap */
int bit_count = length - bit_idx;
if (bit_count > 16)
bit_count = 16;
osbdm->buffer[osbdm->count++] = (uint8_t)bit_count;
/* Copying TMS and TDI data to output buffer */
uint32_t tms_data = buf_get_u32(tms, bit_idx, bit_count);
uint32_t tdi_data = buf_get_u32(tdi, bit_idx, bit_count);
osbdm->buffer[osbdm->count++] = (uint8_t)(tdi_data >> 8);
osbdm->buffer[osbdm->count++] = (uint8_t)tdi_data;
osbdm->buffer[osbdm->count++] = (uint8_t)(tms_data >> 8);
osbdm->buffer[osbdm->count++] = (uint8_t)tms_data;
/* Next bit offset */
bit_idx += bit_count;
}
assert(osbdm->count <= OSBDM_USB_BUFSIZE);
/* Sending data
*/
if (osbdm_send_and_recv(osbdm) != ERROR_OK)
return ERROR_FAIL;
/* Extra check
*/
if (((osbdm->buffer[2] << 8) | osbdm->buffer[3]) != 2 * swap_count) {
LOG_ERROR("OSBDM communnication error: not proper answer to swap command");
return ERROR_FAIL;
}
/* Copy TDO responce
*/
uint8_t *buffer = (uint8_t *)osbdm->buffer + 4;
for (int bit_idx = 0; bit_idx < length; ) {
int bit_count = length - bit_idx;
if (bit_count > 16)
bit_count = 16;
/* Prepare data */
uint32_t tdo_data = 0;
tdo_data |= (*buffer++) << 8;
tdo_data |= (*buffer++);
tdo_data >>= (16 - bit_count);
/* Copy TDO to return */
buf_set_u32(tdo, bit_idx, bit_count, tdo_data);
bit_idx += bit_count;
}
return ERROR_OK;
}
static int osbdm_flush(struct osbdm *osbdm, struct queue* queue)
{
uint8_t tms[DIV_ROUND_UP(OSBDM_SWAP_MAX, 8)];
uint8_t tdi[DIV_ROUND_UP(OSBDM_SWAP_MAX, 8)];
uint8_t tdo[DIV_ROUND_UP(OSBDM_SWAP_MAX, 8)];
int seq_back_len = 0;
while (queue->head) {
(void)memset(tms, 0, sizeof(tms));
(void)memset(tdi, 0, sizeof(tdi));
(void)memset(tdo, 0, sizeof(tdo));
int seq_len;
int swap_len;
struct sequence *seq;
/* Copy from queue to tms/tdi streams
*/
seq = queue->head;
seq_len = seq_back_len;
swap_len = 0;
while (seq && swap_len != OSBDM_SWAP_MAX) {
/* Count bit for copy at this iteration.
* len should fit into remaining space
* in tms/tdo bitstreams
*/
int len = seq->len - seq_len;
if (len > OSBDM_SWAP_MAX - swap_len)
len = OSBDM_SWAP_MAX - swap_len;
/* Set tms data */
buf_set_buf(seq->tms, seq_len, tms, swap_len, len);
/* Set tdi data if they exists */
if (seq->tdi)
buf_set_buf(seq->tdi, seq_len, tdi, swap_len, len);
swap_len += len;
seq_len += len;
if (seq_len == seq->len) {
seq = seq->next; /* Move to next sequence */
seq_len = 0;
}
}
if (osbdm_swap(osbdm, tms, tdi, tdo, swap_len))
return ERROR_FAIL;
/* Copy from tdo stream to queue
*/
for (int swap_back_len = 0; swap_back_len < swap_len; ) {
int len = queue->head->len - seq_back_len;
if (len > swap_len - swap_back_len)
len = swap_len - swap_back_len;
if (queue->head->tdo)
buf_set_buf(tdo, swap_back_len, queue->head->tdo, seq_back_len, len);
swap_back_len += len;
seq_back_len += len;
if (seq_back_len == queue->head->len) {
queue_drop_head(queue);
seq_back_len = 0;
}
}
}
return ERROR_OK;
}
/* Basic operation for opening USB device */
static int osbdm_open(struct osbdm *osbdm)
{
(void)memset(osbdm, 0, sizeof(*osbdm));
if (jtag_libusb_open(osbdm_vid, osbdm_pid, &osbdm->devh) != ERROR_OK)
return ERROR_FAIL;
if (jtag_libusb_claim_interface(osbdm->devh, 0) != ERROR_OK)
return ERROR_FAIL;
return ERROR_OK;
}
static int osbdm_quit(void)
{
jtag_libusb_close(osbdm_context.devh);
return ERROR_OK;
}
static int osbdm_add_pathmove(
struct queue *queue,
tap_state_t *path,
int num_states)
{
assert(num_states <= 32);
struct sequence *next = queue_add_tail(queue, num_states);
if (!next) {
LOG_ERROR("BUG: can't allocate bit sequence");
return ERROR_FAIL;
}
uint32_t tms = 0;
for (int i = 0; i < num_states; i++) {
if (tap_state_transition(tap_get_state(), 1) == path[i]) {
tms |= (1 << i);
} else if (tap_state_transition(tap_get_state(), 0) == path[i]) {
tms &= ~(1 << i); /* This line not so needed */
} else {
LOG_ERROR("BUG: %s -> %s isn't a valid TAP state transition",
tap_state_name(tap_get_state()),
tap_state_name(path[i]));
return ERROR_FAIL;
}
tap_set_state(path[i]);
}
buf_set_u32(next->tms, 0, num_states, tms);
tap_set_end_state(tap_get_state());
return ERROR_OK;
}
static int osbdm_add_statemove(
struct queue *queue,
tap_state_t new_state,
int skip_first)
{
int len = 0;
int tms;
tap_set_end_state(new_state);
if (tap_get_end_state() == TAP_RESET) {
/* Ignore current state */
tms = 0xff;
len = 5;
} else if (tap_get_state() != tap_get_end_state()) {
tms = tap_get_tms_path(tap_get_state(), new_state);
len = tap_get_tms_path_len(tap_get_state(), new_state);
}
if (len && skip_first) {
len--;
tms >>= 1;
}
if (len) {
struct sequence *next = queue_add_tail(queue, len);
if (!next) {
LOG_ERROR("BUG: can't allocate bit sequence");
return ERROR_FAIL;
}
buf_set_u32(next->tms, 0, len, tms);
}
tap_set_state(tap_get_end_state());
return ERROR_OK;
}
static int osbdm_add_stableclocks(
struct queue *queue,
int count)
{
if (!tap_is_state_stable(tap_get_state())) {
LOG_ERROR("BUG: current state (%s) is not stable",
tap_state_name(tap_get_state()));
return ERROR_FAIL;
}
struct sequence *next = queue_add_tail(queue, count);
if (!next) {
LOG_ERROR("BUG: can't allocate bit sequence");
return ERROR_FAIL;
}
if (tap_get_state() == TAP_RESET)
(void)memset(next->tms, 0xff, DIV_ROUND_UP(count, 8));
return ERROR_OK;
}
static int osbdm_add_tms(
struct queue *queue,
const uint8_t *tms,
int num_bits)
{
struct sequence *next = queue_add_tail(queue, num_bits);
if (!next) {
LOG_ERROR("BUG: can't allocate bit sequence");
return ERROR_FAIL;
}
buf_set_buf(tms, 0, next->tms, 0, num_bits);
return ERROR_OK;
}
static int osbdm_add_scan(
struct queue *queue,
struct scan_field *fields,
int num_fields,
tap_state_t end_state,
bool ir_scan)
{
/* Move to desired shift state */
if (ir_scan) {
if (tap_get_state() != TAP_IRSHIFT) {
if (osbdm_add_statemove(queue, TAP_IRSHIFT, 0) != ERROR_OK)
return ERROR_FAIL;
}
} else {
if (tap_get_state() != TAP_DRSHIFT) {
if (osbdm_add_statemove(queue, TAP_DRSHIFT, 0) != ERROR_OK)
return ERROR_FAIL;
}
}
/* Add scan */
tap_set_end_state(end_state);
for (int idx = 0; idx < num_fields; idx++) {
struct sequence *next = queue_add_tail(queue, fields[idx].num_bits);
if (!next) {
LOG_ERROR("Can't allocate bit sequence");
return ERROR_FAIL;
}
(void)memset(next->tms, 0, DIV_ROUND_UP(fields[idx].num_bits, 8));
next->tdi = fields[idx].out_value;
next->tdo = fields[idx].in_value;
}
/* Move to end state
*/
if (tap_get_state() != tap_get_end_state()) {
/* Exit from IRSHIFT/DRSHIFT */
buf_set_u32(queue->tail->tms, queue->tail->len - 1, 1, 1);
/* Move with skip_first flag */
if (osbdm_add_statemove(queue, tap_get_end_state(), 1) != ERROR_OK)
return ERROR_FAIL;
}
return ERROR_OK;
}
static int osbdm_add_runtest(
struct queue *queue,
int num_cycles,
tap_state_t end_state)
{
if (osbdm_add_statemove(queue, TAP_IDLE, 0) != ERROR_OK)
return ERROR_FAIL;
if (osbdm_add_stableclocks(queue, num_cycles) != ERROR_OK)
return ERROR_FAIL;
if (osbdm_add_statemove(queue, end_state, 0) != ERROR_OK)
return ERROR_FAIL;
return ERROR_OK;
}
static int osbdm_execute_command(
struct osbdm *osbdm,
struct queue *queue,
struct jtag_command *cmd)
{
int retval = ERROR_OK;
switch (cmd->type) {
case JTAG_RESET:
if (cmd->cmd.reset->trst) {
LOG_ERROR("BUG: nTRST signal is not supported");
retval = ERROR_FAIL;
} else {
retval = osbdm_flush(osbdm, queue);
if (retval == ERROR_OK)
retval = osbdm_srst(osbdm, cmd->cmd.reset->srst);
}
break;
case JTAG_PATHMOVE:
retval = osbdm_add_pathmove(
queue,
cmd->cmd.pathmove->path,
cmd->cmd.pathmove->num_states);
break;
case JTAG_TLR_RESET:
retval = osbdm_add_statemove(
queue,
cmd->cmd.statemove->end_state,
0);
break;
case JTAG_STABLECLOCKS:
retval = osbdm_add_stableclocks(
queue,
cmd->cmd.stableclocks->num_cycles);
break;
case JTAG_TMS:
retval = osbdm_add_tms(
queue,
cmd->cmd.tms->bits,
cmd->cmd.tms->num_bits);
break;
case JTAG_SCAN:
retval = osbdm_add_scan(
queue,
cmd->cmd.scan->fields,
cmd->cmd.scan->num_fields,
cmd->cmd.scan->end_state,
cmd->cmd.scan->ir_scan);
break;
case JTAG_SLEEP:
retval = osbdm_flush(osbdm, queue);
if (retval == ERROR_OK)
jtag_sleep(cmd->cmd.sleep->us);
break;
case JTAG_RUNTEST:
retval = osbdm_add_runtest(
queue,
cmd->cmd.runtest->num_cycles,
cmd->cmd.runtest->end_state);
break;
default:
LOG_ERROR("BUG: unknown JTAG command type encountered");
retval = ERROR_FAIL;
break;
}
return retval;
}
static int osbdm_execute_queue(void)
{
int retval = ERROR_OK;
struct queue *queue = queue_alloc();
if (!queue) {
LOG_ERROR("BUG: can't allocate bit queue");
retval = ERROR_FAIL;
} else {
struct jtag_command *cmd = jtag_command_queue;
while (retval == ERROR_OK && cmd) {
retval = osbdm_execute_command(&osbdm_context, queue, cmd);
cmd = cmd->next;
}
if (retval == ERROR_OK)
retval = osbdm_flush(&osbdm_context, queue);
queue_free(queue);
}
if (retval != ERROR_OK) {
LOG_ERROR("FATAL: can't execute jtag command");
exit(-1);
}
return retval;
}
static int osbdm_init(void)
{
/* Open device */
if (osbdm_open(&osbdm_context) != ERROR_OK) {
LOG_ERROR("Can't open OSBDM device");
return ERROR_FAIL;
} else {
/* Device successfully opened */
LOG_INFO("OSBDM has opened");
}
/* Perform initialize command */
osbdm_context.count = 0;
osbdm_context.buffer[osbdm_context.count++] = OSBDM_CMD_INIT;
if (osbdm_send_and_recv(&osbdm_context) != ERROR_OK)
return ERROR_FAIL;
return ERROR_OK;
}
static int osbdm_khz(int khz, int *speed)
{
*speed = khz;
return ERROR_OK;
}
static int osbdm_speed(int speed)
{
return ERROR_OK;
}
static int osbdm_speed_div(int speed, int *khz)
{
*khz = speed;
return ERROR_OK;
}
struct jtag_interface osbdm_interface = {
.name = "osbdm",
.transports = jtag_only,
.execute_queue = osbdm_execute_queue,
.khz = osbdm_khz,
.speed = osbdm_speed,
.speed_div = osbdm_speed_div,
.init = osbdm_init,
.quit = osbdm_quit
};

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@ -104,6 +104,9 @@ extern struct jtag_interface remote_bitbang_interface;
#if BUILD_STLINK == 1
extern struct jtag_interface stlink_interface;
#endif
#if BUILD_OSBDM == 1
extern struct jtag_interface osbdm_interface;
#endif
#endif /* standard drivers */
/**
@ -176,6 +179,9 @@ struct jtag_interface *jtag_interfaces[] = {
#if BUILD_STLINK == 1
&stlink_interface,
#endif
#if BUILD_OSBDM == 1
&osbdm_interface,
#endif
#endif /* standard drivers */
NULL,
};

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@ -1,10 +1,12 @@
#
# Freescale KwikStik development board
# Freescale TWRK60N512 development board
#
source [find target/k60.cfg]
reset_config trst_and_srst
$_TARGETNAME configure -event reset-init {
puts "-event reset-init occured"
}
#
# Bank definition for the 'program flash' (instructions and/or data)

12
tcl/interface/osbdm.cfg Normal file
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@ -0,0 +1,12 @@
#
# P&E Micro OSBDM (aka OSJTAG) interface
#
# http://pemicro.com/osbdm/
#
interface osbdm
reset_config srst_only
#
# OSBDM doesn't support speed control
#
adapter_khz 1