update files to correct FSF address

[openocd.git] / src / jtag / drivers / OpenULINK / src / jtag.c

/***************************************************************************
 *   Copyright (C) 2011 by Martin Schmoelzer                               *
 *   <martin.schmoelzer@student.tuwien.ac.at>                              *
 *                                                                         *
 *   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.,                                       *
 *   51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.           *
 ***************************************************************************/

#include "jtag.h"

#include "io.h"
#include "msgtypes.h"
#include "common.h"

#include <stdbool.h>

/** Delay value for SCAN_IN operations with less than maximum TCK frequency */
uint8_t delay_scan_in;

/** Delay value for SCAN_OUT operations with less than maximum TCK frequency */
uint8_t delay_scan_out;

/** Delay value for SCAN_IO operations with less than maximum TCK frequency */
uint8_t delay_scan_io;

/** Delay value for CLOCK_TCK operations with less than maximum frequency */
uint8_t delay_tck;

/** Delay value for CLOCK_TMS operations with less than maximum frequency */
uint8_t delay_tms;

/**
 * Perform JTAG SCAN-IN operation at maximum TCK frequency.
 *
 * Dummy data is shifted into the JTAG chain via TDI, TDO data is sampled and
 * stored in the EP2 IN buffer.
 *
 * Maximum achievable TCK frequency is 182 kHz for ULINK clocked at 24 MHz.
 *
 * @param out_offset offset in OUT2BUF where payload data starts
 */
void jtag_scan_in(uint8_t out_offset, uint8_t in_offset)
{
        uint8_t scan_size_bytes, bits_last_byte;
        uint8_t tms_count_start, tms_count_end;
        uint8_t tms_sequence_start, tms_sequence_end;
        uint8_t tdo_data, i, j;

        uint8_t outb_buffer;

        /* Get parameters from OUT2BUF */
        scan_size_bytes = OUT2BUF[out_offset];
        bits_last_byte = OUT2BUF[out_offset + 1];
        tms_count_start = (OUT2BUF[out_offset + 2] >> 4) & 0x0F;
        tms_count_end = OUT2BUF[out_offset + 2] & 0x0F;
        tms_sequence_start = OUT2BUF[out_offset + 3];
        tms_sequence_end = OUT2BUF[out_offset + 4];

        if (tms_count_start > 0)
                jtag_clock_tms(tms_count_start, tms_sequence_start);

        outb_buffer = OUTB & ~(PIN_TDI | PIN_TCK | PIN_TMS);

        /* Shift all bytes except the last byte */
        for (i = 0; i < scan_size_bytes - 1; i++) {
                tdo_data = 0;

                for (j = 0; j < 8; j++) {
                        OUTB = outb_buffer;     /* TCK changes here */
                        tdo_data = tdo_data >> 1;
                        OUTB = (outb_buffer | PIN_TCK);

                        if (GET_TDO())
                                tdo_data |= 0x80;
                }

                /* Copy TDO data to IN2BUF */
                IN2BUF[i + in_offset] = tdo_data;
        }

        tdo_data = 0;

        /* Shift the last byte */
        for (j = 0; j < bits_last_byte; j++) {
                /* Assert TMS signal if requested and this is the last bit */
                if ((j == bits_last_byte - 1) && (tms_count_end > 0)) {
                        outb_buffer |= PIN_TMS;
                        tms_count_end--;
                        tms_sequence_end = tms_sequence_end >> 1;
                }

                OUTB = outb_buffer;     /* TCK change here */
                tdo_data = tdo_data >> 1;
                OUTB = (outb_buffer | PIN_TCK);

                if (GET_TDO())
                        tdo_data |= 0x80;
        }
        tdo_data = tdo_data >> (8 - bits_last_byte);

        /* Copy TDO data to IN2BUF */
        IN2BUF[i + in_offset] = tdo_data;

        /* Move to correct end state */
        if (tms_count_end > 0)
                jtag_clock_tms(tms_count_end, tms_sequence_end);
}

/**
 * Perform JTAG SCAN-IN operation at variable TCK frequency.
 *
 * Dummy data is shifted into the JTAG chain via TDI, TDO data is sampled and
 * stored in the EP2 IN buffer.
 *
 * Maximum achievable TCK frequency is 113 kHz for ULINK clocked at 24 MHz.
 *
 * @param out_offset offset in OUT2BUF where payload data starts
 */
void jtag_slow_scan_in(uint8_t out_offset, uint8_t in_offset)
{
        uint8_t scan_size_bytes, bits_last_byte;
        uint8_t tms_count_start, tms_count_end;
        uint8_t tms_sequence_start, tms_sequence_end;
        uint8_t tdo_data, i, j, k;

        uint8_t outb_buffer;

        /* Get parameters from OUT2BUF */
        scan_size_bytes = OUT2BUF[out_offset];
        bits_last_byte = OUT2BUF[out_offset + 1];
        tms_count_start = (OUT2BUF[out_offset + 2] >> 4) & 0x0F;
        tms_count_end = OUT2BUF[out_offset + 2] & 0x0F;
        tms_sequence_start = OUT2BUF[out_offset + 3];
        tms_sequence_end = OUT2BUF[out_offset + 4];

        if (tms_count_start > 0)
                jtag_slow_clock_tms(tms_count_start, tms_sequence_start);

        outb_buffer = OUTB & ~(PIN_TDI | PIN_TCK | PIN_TMS);

        /* Shift all bytes except the last byte */
        for (i = 0; i < scan_size_bytes - 1; i++) {
                tdo_data = 0;

                for (j = 0; j < 8; j++) {
                        OUTB = outb_buffer;     /* TCK changes here */
                        for (k = 0; k < delay_scan_in; k++)
                                ;
                        tdo_data = tdo_data >> 1;

                        OUTB = (outb_buffer | PIN_TCK);
                        for (k = 0; k < delay_scan_in; k++)
                                ;

                        if (GET_TDO())
                                tdo_data |= 0x80;
                }

                /* Copy TDO data to IN2BUF */
                IN2BUF[i + in_offset] = tdo_data;
        }

        tdo_data = 0;

        /* Shift the last byte */
        for (j = 0; j < bits_last_byte; j++) {
                /* Assert TMS signal if requested and this is the last bit */
                if ((j == bits_last_byte - 1) && (tms_count_end > 0)) {
                        outb_buffer |= PIN_TMS;
                        tms_count_end--;
                        tms_sequence_end = tms_sequence_end >> 1;
                }

                OUTB = outb_buffer;     /* TCK change here */
                for (k = 0; k < delay_scan_in; k++)
                        ;
                tdo_data = tdo_data >> 1;

                OUTB = (outb_buffer | PIN_TCK);
                for (k = 0; k < delay_scan_in; k++)
                        ;

                if (GET_TDO())
                        tdo_data |= 0x80;
        }
        tdo_data = tdo_data >> (8 - bits_last_byte);

        /* Copy TDO data to IN2BUF */
        IN2BUF[i + in_offset] = tdo_data;

        /* Move to correct end state */
        if (tms_count_end > 0)
                jtag_slow_clock_tms(tms_count_end, tms_sequence_end);
}

/**
 * Perform JTAG SCAN-OUT operation at maximum TCK frequency.
 *
 * Data stored in EP2 OUT buffer is shifted into the JTAG chain via TDI, TDO
 * data is not sampled.
 * The TAP-FSM state is alyways left in the PAUSE-DR/PAUSE-IR state.
 *
 * Maximum achievable TCK frequency is 142 kHz for ULINK clocked at 24 MHz.
 *
 * @param out_offset offset in OUT2BUF where payload data starts
 */
void jtag_scan_out(uint8_t out_offset)
{
        uint8_t scan_size_bytes, bits_last_byte;
        uint8_t tms_count_start, tms_count_end;
        uint8_t tms_sequence_start, tms_sequence_end;
        uint8_t tdi_data, i, j;

        uint8_t outb_buffer;

        /* Get parameters from OUT2BUF */
        scan_size_bytes = OUT2BUF[out_offset];
        bits_last_byte = OUT2BUF[out_offset + 1];
        tms_count_start = (OUT2BUF[out_offset + 2] >> 4) & 0x0F;
        tms_count_end = OUT2BUF[out_offset + 2] & 0x0F;
        tms_sequence_start = OUT2BUF[out_offset + 3];
        tms_sequence_end = OUT2BUF[out_offset + 4];

        if (tms_count_start > 0)
                jtag_clock_tms(tms_count_start, tms_sequence_start);

        outb_buffer = OUTB & ~(PIN_TCK | PIN_TMS);

        /* Shift all bytes except the last byte */
        for (i = 0; i < scan_size_bytes - 1; i++) {
                tdi_data = OUT2BUF[i + out_offset + 5];

                for (j = 0; j < 8; j++) {
                        if (tdi_data & 0x01)
                                outb_buffer |= PIN_TDI;
                        else
                                outb_buffer &= ~PIN_TDI;

                        OUTB = outb_buffer;     /* TDI and TCK change here */
                        tdi_data = tdi_data >> 1;
                        OUTB = (outb_buffer | PIN_TCK);
                }
        }

        tdi_data = OUT2BUF[i + out_offset + 5];

        /* Shift the last byte */
        for (j = 0; j < bits_last_byte; j++) {
                if (tdi_data & 0x01)
                        outb_buffer |= PIN_TDI;
                else
                        outb_buffer &= ~PIN_TDI;

                /* Assert TMS signal if requested and this is the last bit */
                if ((j == bits_last_byte - 1) && (tms_count_end > 0)) {
                        outb_buffer |= PIN_TMS;
                        tms_count_end--;
                        tms_sequence_end = tms_sequence_end >> 1;
                }

                OUTB = outb_buffer;     /* TDI and TCK change here */
                tdi_data = tdi_data >> 1;
                OUTB = (outb_buffer | PIN_TCK);
        }

        /* Move to correct end state */
        if (tms_count_end > 0)
                jtag_clock_tms(tms_count_end, tms_sequence_end);
}

/**
 * Perform JTAG SCAN-OUT operation at maximum TCK frequency.
 *
 * Data stored in EP2 OUT buffer is shifted into the JTAG chain via TDI, TDO
 * data is not sampled.
 * The TAP-FSM state is alyways left in the PAUSE-DR/PAUSE-IR state.
 *
 * Maximum achievable TCK frequency is 97 kHz for ULINK clocked at 24 MHz.
 *
 * @param out_offset offset in OUT2BUF where payload data starts
 */
void jtag_slow_scan_out(uint8_t out_offset)
{
        uint8_t scan_size_bytes, bits_last_byte;
        uint8_t tms_count_start, tms_count_end;
        uint8_t tms_sequence_start, tms_sequence_end;
        uint8_t tdi_data, i, j, k;

        uint8_t outb_buffer;

        /* Get parameters from OUT2BUF */
        scan_size_bytes = OUT2BUF[out_offset];
        bits_last_byte = OUT2BUF[out_offset + 1];
        tms_count_start = (OUT2BUF[out_offset + 2] >> 4) & 0x0F;
        tms_count_end = OUT2BUF[out_offset + 2] & 0x0F;
        tms_sequence_start = OUT2BUF[out_offset + 3];
        tms_sequence_end = OUT2BUF[out_offset + 4];

        if (tms_count_start > 0)
                jtag_slow_clock_tms(tms_count_start, tms_sequence_start);

        outb_buffer = OUTB & ~(PIN_TCK | PIN_TMS);

        /* Shift all bytes except the last byte */
        for (i = 0; i < scan_size_bytes - 1; i++) {
                tdi_data = OUT2BUF[i + out_offset + 5];

                for (j = 0; j < 8; j++) {
                        if (tdi_data & 0x01)
                                outb_buffer |= PIN_TDI;
                        else
                                outb_buffer &= ~PIN_TDI;

                        OUTB = outb_buffer;     /* TDI and TCK change here */
                        for (k = 0; k < delay_scan_out; k++)
                                ;
                        tdi_data = tdi_data >> 1;

                        OUTB = (outb_buffer | PIN_TCK);
                        for (k = 0; k < delay_scan_out; k++)
                                ;
                }
        }

        tdi_data = OUT2BUF[i + out_offset + 5];

        /* Shift the last byte */
        for (j = 0; j < bits_last_byte; j++) {
                if (tdi_data & 0x01)
                        outb_buffer |= PIN_TDI;
                else
                        outb_buffer &= ~PIN_TDI;

                /* Assert TMS signal if requested and this is the last bit */
                if ((j == bits_last_byte - 1) && (tms_count_end > 0)) {
                        outb_buffer |= PIN_TMS;
                        tms_count_end--;
                        tms_sequence_end = tms_sequence_end >> 1;
                }

                OUTB = outb_buffer;     /* TDI and TCK change here */
                for (k = 0; k < delay_scan_out; k++)
                        ;
                tdi_data = tdi_data >> 1;

                OUTB = (outb_buffer | PIN_TCK);
                for (k = 0; k < delay_scan_out; k++)
                        ;
        }

        /* Move to correct end state */
        if (tms_count_end > 0)
                jtag_slow_clock_tms(tms_count_end, tms_sequence_end);
}

/**
 * Perform bidirectional JTAG SCAN operation at maximum TCK frequency.
 *
 * Data stored in EP2 OUT buffer is shifted into the JTAG chain via TDI, TDO
 * data is sampled and stored in the EP2 IN buffer.
 * The TAP-FSM state is alyways left in the PAUSE-DR/PAUSE-IR state.
 *
 * Maximum achievable TCK frequency is 100 kHz for ULINK clocked at 24 MHz.
 *
 * @param out_offset offset in OUT2BUF where payload data starts
 */
void jtag_scan_io(uint8_t out_offset, uint8_t in_offset)
{
        uint8_t scan_size_bytes, bits_last_byte;
        uint8_t tms_count_start, tms_count_end;
        uint8_t tms_sequence_start, tms_sequence_end;
        uint8_t tdi_data, tdo_data, i, j;

        uint8_t outb_buffer;

        /* Get parameters from OUT2BUF */
        scan_size_bytes = OUT2BUF[out_offset];
        bits_last_byte = OUT2BUF[out_offset + 1];
        tms_count_start = (OUT2BUF[out_offset + 2] >> 4) & 0x0F;
        tms_count_end = OUT2BUF[out_offset + 2] & 0x0F;
        tms_sequence_start = OUT2BUF[out_offset + 3];
        tms_sequence_end = OUT2BUF[out_offset + 4];

        if (tms_count_start > 0)
                jtag_clock_tms(tms_count_start, tms_sequence_start);

        outb_buffer = OUTB & ~(PIN_TCK | PIN_TMS);

        /* Shift all bytes except the last byte */
        for (i = 0; i < scan_size_bytes - 1; i++) {
                tdi_data = OUT2BUF[i + out_offset + 5];
                tdo_data = 0;

                for (j = 0; j < 8; j++) {
                        if (tdi_data & 0x01)
                                outb_buffer |= PIN_TDI;
                        else
                                outb_buffer &= ~PIN_TDI;

                        OUTB = outb_buffer;     /* TDI and TCK change here */
                        tdi_data = tdi_data >> 1;
                        OUTB = (outb_buffer | PIN_TCK);
                        tdo_data = tdo_data >> 1;

                        if (GET_TDO())
                                tdo_data |= 0x80;
                }

                /* Copy TDO data to IN2BUF */
                IN2BUF[i + in_offset] = tdo_data;
        }

        tdi_data = OUT2BUF[i + out_offset + 5];
        tdo_data = 0;

        /* Shift the last byte */
        for (j = 0; j < bits_last_byte; j++) {
                if (tdi_data & 0x01)
                        outb_buffer |= PIN_TDI;
                else
                        outb_buffer &= ~PIN_TDI;

                /* Assert TMS signal if requested and this is the last bit */
                if ((j == bits_last_byte - 1) && (tms_count_end > 0)) {
                        outb_buffer |= PIN_TMS;
                        tms_count_end--;
                        tms_sequence_end = tms_sequence_end >> 1;
                }

                OUTB = outb_buffer;     /* TDI and TCK change here */
                tdi_data = tdi_data >> 1;
                OUTB = (outb_buffer | PIN_TCK);
                tdo_data = tdo_data >> 1;

                if (GET_TDO())
                        tdo_data |= 0x80;
        }
        tdo_data = tdo_data >> (8 - bits_last_byte);

        /* Copy TDO data to IN2BUF */
        IN2BUF[i + in_offset] = tdo_data;

        /* Move to correct end state */
        if (tms_count_end > 0)
                jtag_clock_tms(tms_count_end, tms_sequence_end);
}

/**
 * Perform bidirectional JTAG SCAN operation at maximum TCK frequency.
 *
 * Data stored in EP2 OUT buffer is shifted into the JTAG chain via TDI, TDO
 * data is sampled and stored in the EP2 IN buffer.
 * The TAP-FSM state is alyways left in the PAUSE-DR/PAUSE-IR state.
 *
 * Maximum achievable TCK frequency is 78 kHz for ULINK clocked at 24 MHz.
 *
 * @param out_offset offset in OUT2BUF where payload data starts
 */
void jtag_slow_scan_io(uint8_t out_offset, uint8_t in_offset)
{
        uint8_t scan_size_bytes, bits_last_byte;
        uint8_t tms_count_start, tms_count_end;
        uint8_t tms_sequence_start, tms_sequence_end;
        uint8_t tdi_data, tdo_data, i, j, k;

        uint8_t outb_buffer;

        /* Get parameters from OUT2BUF */
        scan_size_bytes = OUT2BUF[out_offset];
        bits_last_byte = OUT2BUF[out_offset + 1];
        tms_count_start = (OUT2BUF[out_offset + 2] >> 4) & 0x0F;
        tms_count_end = OUT2BUF[out_offset + 2] & 0x0F;
        tms_sequence_start = OUT2BUF[out_offset + 3];
        tms_sequence_end = OUT2BUF[out_offset + 4];

        if (tms_count_start > 0)
                jtag_slow_clock_tms(tms_count_start, tms_sequence_start);

        outb_buffer = OUTB & ~(PIN_TCK | PIN_TMS);

        /* Shift all bytes except the last byte */
        for (i = 0; i < scan_size_bytes - 1; i++) {
                tdi_data = OUT2BUF[i + out_offset + 5];
                tdo_data = 0;

                for (j = 0; j < 8; j++) {
                        if (tdi_data & 0x01)
                                outb_buffer |= PIN_TDI;
                        else
                                outb_buffer &= ~PIN_TDI;

                        OUTB = outb_buffer;     /* TDI and TCK change here */
                        for (k = 0; k < delay_scan_io; k++)
                                ;
                        tdi_data = tdi_data >> 1;

                        OUTB = (outb_buffer | PIN_TCK);
                        for (k = 0; k < delay_scan_io; k++)
                                ;
                        tdo_data = tdo_data >> 1;

                        if (GET_TDO())
                                tdo_data |= 0x80;
                }

                /* Copy TDO data to IN2BUF */
                IN2BUF[i + in_offset] = tdo_data;
        }

        tdi_data = OUT2BUF[i + out_offset + 5];
        tdo_data = 0;

        /* Shift the last byte */
        for (j = 0; j < bits_last_byte; j++) {
                if (tdi_data & 0x01)
                        outb_buffer |= PIN_TDI;
                else
                        outb_buffer &= ~PIN_TDI;

                /* Assert TMS signal if requested and this is the last bit */
                if ((j == bits_last_byte - 1) && (tms_count_end > 0)) {
                        outb_buffer |= PIN_TMS;
                        tms_count_end--;
                        tms_sequence_end = tms_sequence_end >> 1;
                }

                OUTB = outb_buffer;     /* TDI and TCK change here */
                for (k = 0; k < delay_scan_io; k++)
                        ;
                tdi_data = tdi_data >> 1;

                OUTB = (outb_buffer | PIN_TCK);
                for (k = 0; k < delay_scan_io; k++)
                        ;
                tdo_data = tdo_data >> 1;

                if (GET_TDO())
                        tdo_data |= 0x80;
        }
        tdo_data = tdo_data >> (8 - bits_last_byte);

        /* Copy TDO data to IN2BUF */
        IN2BUF[i + in_offset] = tdo_data;

        /* Move to correct end state */
        if (tms_count_end > 0)
                jtag_slow_clock_tms(tms_count_end, tms_sequence_end);
}

/**
 * Generate TCK clock cycles.
 *
 * Maximum achievable TCK frequency is 375 kHz for ULINK clocked at 24 MHz.
 *
 * @param count number of TCK clock cyclces to generate.
 */
void jtag_clock_tck(uint16_t count)
{
        uint16_t i;
        uint8_t outb_buffer = OUTB & ~(PIN_TCK);

        for (i = 0; i < count; i++) {
                OUTB = outb_buffer;
                OUTB = outb_buffer | PIN_TCK;
        }
}

/**
 * Generate TCK clock cycles at variable frequency.
 *
 * Maximum achieveable TCK frequency is 166.6 kHz for ULINK clocked at 24 MHz.
 *
 * @param count number of TCK clock cyclces to generate.
 */
void jtag_slow_clock_tck(uint16_t count)
{
        uint16_t i;
        uint8_t j;
        uint8_t outb_buffer = OUTB & ~(PIN_TCK);

        for (i = 0; i < count; i++) {
                OUTB = outb_buffer;
                for (j = 0; j < delay_tck; j++)
                        ;
                OUTB = outb_buffer | PIN_TCK;
                for (j = 0; j < delay_tck; j++)
                        ;
        }
}

/**
 * Perform TAP FSM state transitions at maximum TCK frequency.
 *
 * Maximum achievable TCK frequency is 176 kHz for ULINK clocked at 24 MHz.
 *
 * @param count the number of state transitions to perform.
 * @param sequence the TMS pin levels for each state transition, starting with
 *  the least-significant bit.
 */
void jtag_clock_tms(uint8_t count, uint8_t sequence)
{
        uint8_t outb_buffer = OUTB & ~(PIN_TCK);
        uint8_t i;

        for (i = 0; i < count; i++) {
                /* Set TMS pin according to sequence parameter */
                if (sequence & 0x1)
                        outb_buffer |= PIN_TMS;
                else
                        outb_buffer &= ~PIN_TMS;

                OUTB = outb_buffer;
                sequence = sequence >> 1;
                OUTB = outb_buffer | PIN_TCK;
        }
}

/**
 * Perform TAP-FSM state transitions at less than maximum TCK frequency.
 *
 * Maximum achievable TCK frequency is 117 kHz for ULINK clocked at 24 MHz.
 *
 * @param count the number of state transitions to perform.
 * @param sequence the TMS pin levels for each state transition, starting with
 *  the least-significant bit.
 */
void jtag_slow_clock_tms(uint8_t count, uint8_t sequence)
{
        uint8_t outb_buffer = OUTB & ~(PIN_TCK);
        uint8_t i, j;

        for (i = 0; i < count; i++) {
                /* Set TMS pin according to sequence parameter */
                if (sequence & 0x1)
                        outb_buffer |= PIN_TMS;
                else
                        outb_buffer &= ~PIN_TMS;

                OUTB = outb_buffer;
                for (j = 0; j < delay_tms; j++)
                        ;
                sequence = sequence >> 1;
                OUTB = outb_buffer | PIN_TCK;
                for (j = 0; j < delay_tms; j++)
                        ;
        }
}

/**
 * Get current JTAG signal states.
 *
 * @return a 16-bit integer where the most-significant byte contains the state
 *  of the JTAG input signals and the least-significant byte cotains the state
 *  of the JTAG output signals.
 */
uint16_t jtag_get_signals(void)
{
        uint8_t input_signal_state, output_signal_state;

        input_signal_state = 0;
        output_signal_state = 0;

        /* Get states of input pins */
        if (GET_TDO())
                input_signal_state |= SIGNAL_TDO;
        if (GET_BRKOUT())
                input_signal_state |= SIGNAL_BRKOUT;
        if (GET_TRAP())
                input_signal_state |= SIGNAL_TRAP;
        if (GET_RTCK()) {
                /* Using RTCK this way would be extremely slow,
                 * implemented only for the sake of completeness */
                input_signal_state |= SIGNAL_RTCK;
        }

        /* Get states of output pins */
        output_signal_state = PINSB & MASK_PORTB_DIRECTION_OUT;

        return ((uint16_t)input_signal_state << 8) | ((uint16_t)output_signal_state);
}

/**
 * Set state of JTAG output signals.
 *
 * @param low signals which should be de-asserted.
 * @param high signals which should be asserted.
 */
void jtag_set_signals(uint8_t low, uint8_t high)
{
        OUTB &= ~(low & MASK_PORTB_DIRECTION_OUT);
        OUTB |= (high & MASK_PORTB_DIRECTION_OUT);
}

/**
 * Configure TCK delay parameters.
 *
 * @param scan_in number of delay cycles in scan_in operations.
 * @param scan_out number of delay cycles in scan_out operations.
 * @param scan_io number of delay cycles in scan_io operations.
 * @param tck number of delay cycles in clock_tck operations.
 * @param tms number of delay cycles in clock_tms operations.
 */
void jtag_configure_tck_delay(uint8_t scan_in, uint8_t scan_out,
        uint8_t scan_io, uint8_t tck, uint8_t tms)
{
        delay_scan_in = scan_in;
        delay_scan_out = scan_out;
        delay_scan_io = scan_io;
        delay_tck = tck;
        delay_tms = tms;
}