/****************************************************************************
*
* Copyright (c) 2012-2014 PX4 Development Team. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* 3. Neither the name PX4 nor the names of its contributors may be
* used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
****************************************************************************/
#pragma once
/**
* @file protocol.h
*
* PX4IO interface protocol.
*
* Communication is performed via writes to and reads from 16-bit virtual
* registers organised into pages of 255 registers each.
*
* The first two bytes of each write select a page and offset address
* respectively. Subsequent reads and writes increment the offset within
* the page.
*
* Some pages are read- or write-only.
*
* Note that some pages may permit offset values greater than 255, which
* can only be achieved by long writes. The offset does not wrap.
*
* Writes to unimplemented registers are ignored. Reads from unimplemented
* registers return undefined values.
*
* As convention, values that would be floating point in other parts of
* the PX4 system are expressed as signed integer values scaled by 10000,
* e.g. control values range from -10000..10000. Use the REG_TO_SIGNED and
* SIGNED_TO_REG macros to convert between register representation and
* the signed version, and REG_TO_FLOAT/FLOAT_TO_REG to convert to float.
*
* Note that the implementation of readable pages prefers registers within
* readable pages to be densely packed. Page numbers do not need to be
* packed.
*
* Definitions marked [1] are only valid on PX4IOv1 boards. Likewise,
* [2] denotes definitions specific to the PX4IOv2 board.
*/
/* Per C, this is safe for all 2's complement systems */
#define REG_TO_SIGNED(_reg) ((int16_t)(_reg))
#define SIGNED_TO_REG(_signed) ((uint16_t)(_signed))
#define REG_TO_FLOAT(_reg) ((float)REG_TO_SIGNED(_reg) / 10000.0f)
#define FLOAT_TO_REG(_float) SIGNED_TO_REG((int16_t)((_float) * 10000.0f))
#define PX4IO_PROTOCOL_VERSION 4
/* maximum allowable sizes on this protocol version */
#define PX4IO_PROTOCOL_MAX_CONTROL_COUNT 8 /**< The protocol does not support more than set here, individual units might support less - see PX4IO_P_CONFIG_CONTROL_COUNT */
/* static configuration page */
#define PX4IO_PAGE_CONFIG 0
#define PX4IO_P_CONFIG_PROTOCOL_VERSION 0 /* PX4IO_PROTOCOL_VERSION */
#define PX4IO_P_CONFIG_HARDWARE_VERSION 1 /* magic numbers TBD */
#define PX4IO_P_CONFIG_BOOTLOADER_VERSION 2 /* get this how? */
#define PX4IO_P_CONFIG_MAX_TRANSFER 3 /* maximum I2C transfer size */
#define PX4IO_P_CONFIG_CONTROL_COUNT 4 /* hardcoded max control count supported */
#define PX4IO_P_CONFIG_ACTUATOR_COUNT 5 /* hardcoded max actuator output count */
#define PX4IO_P_CONFIG_RC_INPUT_COUNT 6 /* hardcoded max R/C input count supported */
#define PX4IO_P_CONFIG_ADC_INPUT_COUNT 7 /* hardcoded max ADC inputs */
#define PX4IO_P_CONFIG_RELAY_COUNT 8 /* hardcoded # of relay outputs */
#define PX4IO_P_CONFIG_CONTROL_GROUP_COUNT 8 /**< hardcoded # of control groups*/
/* dynamic status page */
#define PX4IO_PAGE_STATUS 1
#define PX4IO_P_STATUS_FREEMEM 0
#define PX4IO_P_STATUS_CPULOAD 1
#define PX4IO_P_STATUS_FLAGS 2 /* monitoring flags */
#define PX4IO_P_STATUS_FLAGS_OUTPUTS_ARMED (1 << 0) /* arm-ok and locally armed */
#define PX4IO_P_STATUS_FLAGS_OVERRIDE (1 << 1) /* in manual override */
#define PX4IO_P_STATUS_FLAGS_RC_OK (1 << 2) /* RC input is valid */
#define PX4IO_P_STATUS_FLAGS_RC_PPM (1 << 3) /* PPM input is valid */
#define PX4IO_P_STATUS_FLAGS_RC_DSM (1 << 4) /* DSM input is valid */
#define PX4IO_P_STATUS_FLAGS_RC_SBUS (1 << 5) /* SBUS input is valid */
#define PX4IO_P_STATUS_FLAGS_FMU_OK (1 << 6) /* controls from FMU are valid */
#define PX4IO_P_STATUS_FLAGS_RAW_PWM (1 << 7) /* raw PWM from FMU is bypassing the mixer */
#define PX4IO_P_STATUS_FLAGS_MIXER_OK (1 << 8) /* mixer is OK */
#define PX4IO_P_STATUS_FLAGS_ARM_SYNC (1 << 9) /* the arming state between IO and FMU is in sync */
#define PX4IO_P_STATUS_FLAGS_INIT_OK (1 << 10) /* initialisation of the IO completed without error */
#define PX4IO_P_STATUS_FLAGS_FAILSAFE (1 << 11) /* failsafe is active */
#define PX4IO_P_STATUS_FLAGS_SAFETY_OFF (1 << 12) /* safety is off */
#define PX4IO_P_STATUS_FLAGS_FMU_INITIALIZED (1 << 13) /* FMU was initialized and OK once */
#define PX4IO_P_STATUS_FLAGS_RC_ST24 (1 << 14) /* SBUS input is valid */
#define PX4IO_P_STATUS_ALARMS 3 /* alarm flags - alarms latch, write 1 to a bit to clear it */
#define PX4IO_P_STATUS_ALARMS_VBATT_LOW (1 << 0) /* [1] VBatt is very close to regulator dropout */
#define PX4IO_P_STATUS_ALARMS_TEMPERATURE (1 << 1) /* board temperature is high */
#define PX4IO_P_STATUS_ALARMS_SERVO_CURRENT (1 << 2) /* [1] servo current limit was exceeded */
#define PX4IO_P_STATUS_ALARMS_ACC_CURRENT (1 << 3) /* [1] accessory current limit was exceeded */
#define PX4IO_P_STATUS_ALARMS_FMU_LOST (1 << 4) /* timed out waiting for controls from FMU */
#define PX4IO_P_STATUS_ALARMS_RC_LOST (1 << 5) /* timed out waiting for RC input */
#define PX4IO_P_STATUS_ALARMS_PWM_ERROR (1 << 6) /* PWM configuration or output was bad */
#define PX4IO_P_STATUS_ALARMS_VSERVO_FAULT (1 << 7) /* [2] VServo was out of the valid range (2.5 - 5.5 V) */
#define PX4IO_P_STATUS_VBATT 4 /* [1] battery voltage in mV */
#define PX4IO_P_STATUS_IBATT 5 /* [1] battery current (raw ADC) */
#define PX4IO_P_STATUS_VSERVO 6 /* [2] servo rail voltage in mV */
#define PX4IO_P_STATUS_VRSSI 7 /* [2] RSSI voltage */
#define PX4IO_P_STATUS_PRSSI 8 /* [2] RSSI PWM value */
/* array of post-mix actuator outputs, -10000..10000 */
#define PX4IO_PAGE_ACTUATORS 2 /* 0..CONFIG_ACTUATOR_COUNT-1 */
/* array of PWM servo output values, microseconds */
#define PX4IO_PAGE_SERVOS 3 /* 0..CONFIG_ACTUATOR_COUNT-1 */
/* array of raw RC input values, microseconds */
#define PX4IO_PAGE_RAW_RC_INPUT 4
#define PX4IO_P_RAW_RC_COUNT 0 /* number of valid channels */
#define PX4IO_P_RAW_RC_FLAGS 1 /* RC detail status flags */
#define PX4IO_P_RAW_RC_FLAGS_FRAME_DROP (1 << 0) /* single frame drop */
#define PX4IO_P_RAW_RC_FLAGS_FAILSAFE (1 << 1) /* receiver is in failsafe mode */
#define PX4IO_P_RAW_RC_FLAGS_RC_DSM11 (1 << 2) /* DSM decoding is 11 bit mode */
#define PX4IO_P_RAW_RC_FLAGS_MAPPING_OK (1 << 3) /* Channel mapping is ok */
#define PX4IO_P_RAW_RC_FLAGS_RC_OK (1 << 4) /* RC reception ok */
#define PX4IO_P_RAW_RC_NRSSI 2 /* [2] Normalized RSSI value, 0: no reception, 255: perfect reception */
#define PX4IO_P_RAW_RC_DATA 3 /* [1] + [2] Details about the RC source (PPM frame length, Spektrum protocol type) */
#define PX4IO_P_RAW_FRAME_COUNT 4 /* Number of total received frames (wrapping counter) */
#define PX4IO_P_RAW_LOST_FRAME_COUNT 5 /* Number of total dropped frames (wrapping counter) */
#define PX4IO_P_RAW_RC_BASE 6 /* CONFIG_RC_INPUT_COUNT channels from here */
/* array of scaled RC input values, -10000..10000 */
#define PX4IO_PAGE_RC_INPUT 5
#define PX4IO_P_RC_VALID 0 /* bitmask of valid controls */
#define PX4IO_P_RC_BASE 1 /* CONFIG_RC_INPUT_COUNT controls from here */
/* array of raw ADC values */
#define PX4IO_PAGE_RAW_ADC_INPUT 6 /* 0..CONFIG_ADC_INPUT_COUNT-1 */
/* PWM servo information */
#define PX4IO_PAGE_PWM_INFO 7
#define PX4IO_RATE_MAP_BASE 0 /* 0..CONFIG_ACTUATOR_COUNT bitmaps of PWM rate groups */
/* setup page */
#define PX4IO_PAGE_SETUP 50
#define PX4IO_P_SETUP_FEATURES 0
#define PX4IO_P_SETUP_FEATURES_SBUS1_OUT (1 << 0) /**< enable S.Bus v1 output */
#define PX4IO_P_SETUP_FEATURES_SBUS2_OUT (1 << 1) /**< enable S.Bus v2 output */
#define PX4IO_P_SETUP_FEATURES_PWM_RSSI (1 << 2) /**< enable PWM RSSI parsing */
#define PX4IO_P_SETUP_FEATURES_ADC_RSSI (1 << 3) /**< enable ADC RSSI parsing */
#define PX4IO_P_SETUP_ARMING 1 /* arming controls */
#define PX4IO_P_SETUP_ARMING_IO_ARM_OK (1 << 0) /* OK to arm the IO side */
#define PX4IO_P_SETUP_ARMING_FMU_ARMED (1 << 1) /* FMU is already armed */
#define PX4IO_P_SETUP_ARMING_MANUAL_OVERRIDE_OK (1 << 2) /* OK to switch to manual override via override RC channel */
#define PX4IO_P_SETUP_ARMING_FAILSAFE_CUSTOM (1 << 3) /* use custom failsafe values, not 0 values of mixer */
#define PX4IO_P_SETUP_ARMING_INAIR_RESTART_OK (1 << 4) /* OK to try in-air restart */
#define PX4IO_P_SETUP_ARMING_ALWAYS_PWM_ENABLE (1 << 5) /* Output of PWM right after startup enabled to help ESCs initialize and prevent them from beeping */
#define PX4IO_P_SETUP_ARMING_RC_HANDLING_DISABLED (1 << 6) /* Disable the IO-internal evaluation of the RC */
#define PX4IO_P_SETUP_ARMING_LOCKDOWN (1 << 7) /* If set, the system operates normally, but won't actuate any servos */
#define PX4IO_P_SETUP_ARMING_FORCE_FAILSAFE (1 << 8) /* If set, the system will always output the failsafe values */
#define PX4IO_P_SETUP_ARMING_TERMINATION_FAILSAFE (1 << 9) /* If set, the system will never return from a failsafe, but remain in failsafe once triggered. */
#define PX4IO_P_SETUP_PWM_RATES 2 /* bitmask, 0 = low rate, 1 = high rate */
#define PX4IO_P_SETUP_PWM_DEFAULTRATE 3 /* 'low' PWM frame output rate in Hz */
#define PX4IO_P_SETUP_PWM_ALTRATE 4 /* 'high' PWM frame output rate in Hz */
#if defined(CONFIG_ARCH_BOARD_PX4IO_V1) || defined(CONFIG_ARCH_BOARD_PX4FMU_V1)
#define PX4IO_P_SETUP_RELAYS 5 /* bitmask of relay/switch outputs, 0 = off, 1 = on */
#define PX4IO_P_SETUP_RELAYS_POWER1 (1<<0) /* hardware rev [1] power relay 1 */
#define PX4IO_P_SETUP_RELAYS_POWER2 (1<<1) /* hardware rev [1] power relay 2 */
#define PX4IO_P_SETUP_RELAYS_ACC1 (1<<2) /* hardware rev [1] accessory power 1 */
#define PX4IO_P_SETUP_RELAYS_ACC2 (1<<3) /* hardware rev [1] accessory power 2 */
#else
#define PX4IO_P_SETUP_RELAYS_PAD 5
#endif
#define PX4IO_P_SETUP_VBATT_SCALE 6 /* hardware rev [1] battery voltage correction factor (float) */
#define PX4IO_P_SETUP_VSERVO_SCALE 6 /* hardware rev [2] servo voltage correction factor (float) */
#define PX4IO_P_SETUP_DSM 7 /* DSM bind state */
enum { /* DSM bind states */
dsm_bind_power_down = 0,
dsm_bind_power_up,
dsm_bind_set_rx_out,
dsm_bind_send_pulses,
dsm_bind_reinit_uart
};
/* 8 */
#define PX4IO_P_SETUP_SET_DEBUG 9 /* debug level for IO board */
#define PX4IO_P_SETUP_REBOOT_BL 10 /* reboot IO into bootloader */
#define PX4IO_REBOOT_BL_MAGIC 14662 /* required argument for reboot (random) */
#define PX4IO_P_SETUP_CRC 11 /* get CRC of IO firmware */
/* storage space of 12 occupied by CRC */
#define PX4IO_P_SETUP_FORCE_SAFETY_OFF 12 /* force safety switch into
'armed' (PWM enabled) state - this is a non-data write and
hence index 12 can safely be used. */
#define PX4IO_P_SETUP_RC_THR_FAILSAFE_US 13 /**< the throttle failsafe pulse length in microseconds */
#define PX4IO_FORCE_SAFETY_MAGIC 22027 /* required argument for force safety (random) */
/* autopilot control values, -10000..10000 */
#define PX4IO_PAGE_CONTROLS 51 /**< actuator control groups, one after the other, 8 wide */
#define PX4IO_P_CONTROLS_GROUP_0 (PX4IO_PROTOCOL_MAX_CONTROL_COUNT * 0) /**< 0..PX4IO_PROTOCOL_MAX_CONTROL_COUNT - 1 */
#define PX4IO_P_CONTROLS_GROUP_1 (PX4IO_PROTOCOL_MAX_CONTROL_COUNT * 1) /**< 0..PX4IO_PROTOCOL_MAX_CONTROL_COUNT - 1 */
#define PX4IO_P_CONTROLS_GROUP_2 (PX4IO_PROTOCOL_MAX_CONTROL_COUNT * 2) /**< 0..PX4IO_PROTOCOL_MAX_CONTROL_COUNT - 1 */
#define PX4IO_P_CONTROLS_GROUP_3 (PX4IO_PROTOCOL_MAX_CONTROL_COUNT * 3) /**< 0..PX4IO_PROTOCOL_MAX_CONTROL_COUNT - 1 */
#define PX4IO_P_CONTROLS_GROUP_VALID 64
#define PX4IO_P_CONTROLS_GROUP_VALID_GROUP0 (1 << 0) /**< group 0 is valid / received */
#define PX4IO_P_CONTROLS_GROUP_VALID_GROUP1 (1 << 1) /**< group 1 is valid / received */
#define PX4IO_P_CONTROLS_GROUP_VALID_GROUP2 (1 << 2) /**< group 2 is valid / received */
#define PX4IO_P_CONTROLS_GROUP_VALID_GROUP3 (1 << 3) /**< group 3 is valid / received */
/* raw text load to the mixer parser - ignores offset */
#define PX4IO_PAGE_MIXERLOAD 52
/* R/C channel config */
#define PX4IO_PAGE_RC_CONFIG 53 /**< R/C input configuration */
#define PX4IO_P_RC_CONFIG_MIN 0 /**< lowest input value */
#define PX4IO_P_RC_CONFIG_CENTER 1 /**< center input value */
#define PX4IO_P_RC_CONFIG_MAX 2 /**< highest input value */
#define PX4IO_P_RC_CONFIG_DEADZONE 3 /**< band around center that is ignored */
#define PX4IO_P_RC_CONFIG_ASSIGNMENT 4 /**< mapped input value */
#define PX4IO_P_RC_CONFIG_OPTIONS 5 /**< channel options bitmask */
#define PX4IO_P_RC_CONFIG_OPTIONS_ENABLED (1 << 0)
#define PX4IO_P_RC_CONFIG_OPTIONS_REVERSE (1 << 1)
#define PX4IO_P_RC_CONFIG_STRIDE 6 /**< spacing between channel config data */
/* PWM output - overrides mixer */
#define PX4IO_PAGE_DIRECT_PWM 54 /**< 0..CONFIG_ACTUATOR_COUNT-1 */
/* PWM failsafe values - zero disables the output */
#define PX4IO_PAGE_FAILSAFE_PWM 55 /**< 0..CONFIG_ACTUATOR_COUNT-1 */
/* PWM failsafe values - zero disables the output */
#define PX4IO_PAGE_SENSORS 56 /**< Sensors connected to PX4IO */
#define PX4IO_P_SENSORS_ALTITUDE 0 /**< Altitude of an external sensor (HoTT or S.BUS2) */
/* Debug and test page - not used in normal operation */
#define PX4IO_PAGE_TEST 127
#define PX4IO_P_TEST_LED 0 /**< set the amber LED on/off */
/* PWM minimum values for certain ESCs */
#define PX4IO_PAGE_CONTROL_MIN_PWM 106 /**< 0..CONFIG_ACTUATOR_COUNT-1 */
/* PWM maximum values for certain ESCs */
#define PX4IO_PAGE_CONTROL_MAX_PWM 107 /**< 0..CONFIG_ACTUATOR_COUNT-1 */
/* PWM disarmed values that are active, even when SAFETY_SAFE */
#define PX4IO_PAGE_DISARMED_PWM 108 /* 0..CONFIG_ACTUATOR_COUNT-1 */
/**
* As-needed mixer data upload.
*
* This message adds text to the mixer text buffer; the text
* buffer is drained as the definitions are consumed.
*/
#pragma pack(push, 1)
struct px4io_mixdata {
uint16_t f2i_mixer_magic;
#define F2I_MIXER_MAGIC 0x6d74
uint8_t action;
#define F2I_MIXER_ACTION_RESET 0
#define F2I_MIXER_ACTION_APPEND 1
char text[0]; /* actual text size may vary */
};
#pragma pack(pop)
/**
* Serial protocol encapsulation.
*/
#define PKT_MAX_REGS 32 // by agreement w/FMU
#pragma pack(push, 1)
struct IOPacket {
uint8_t count_code;
uint8_t crc;
uint8_t page;
uint8_t offset;
uint16_t regs[PKT_MAX_REGS];
};
#pragma pack(pop)
#define PKT_CODE_READ 0x00 /* FMU->IO read transaction */
#define PKT_CODE_WRITE 0x40 /* FMU->IO write transaction */
#define PKT_CODE_SUCCESS 0x00 /* IO->FMU success reply */
#define PKT_CODE_CORRUPT 0x40 /* IO->FMU bad packet reply */
#define PKT_CODE_ERROR 0x80 /* IO->FMU register op error reply */
#define PKT_CODE_MASK 0xc0
#define PKT_COUNT_MASK 0x3f
#define PKT_COUNT(_p) ((_p).count_code & PKT_COUNT_MASK)
#define PKT_CODE(_p) ((_p).count_code & PKT_CODE_MASK)
#define PKT_SIZE(_p) ((size_t)((uint8_t *)&((_p).regs[PKT_COUNT(_p)]) - ((uint8_t *)&(_p))))
static const uint8_t crc8_tab[256] __attribute__((unused)) =
{
0x00, 0x07, 0x0E, 0x09, 0x1C, 0x1B, 0x12, 0x15,
0x38, 0x3F, 0x36, 0x31, 0x24, 0x23, 0x2A, 0x2D,
0x70, 0x77, 0x7E, 0x79, 0x6C, 0x6B, 0x62, 0x65,
0x48, 0x4F, 0x46, 0x41, 0x54, 0x53, 0x5A, 0x5D,
0xE0, 0xE7, 0xEE, 0xE9, 0xFC, 0xFB, 0xF2, 0xF5,
0xD8, 0xDF, 0xD6, 0xD1, 0xC4, 0xC3, 0xCA, 0xCD,
0x90, 0x97, 0x9E, 0x99, 0x8C, 0x8B, 0x82, 0x85,
0xA8, 0xAF, 0xA6, 0xA1, 0xB4, 0xB3, 0xBA, 0xBD,
0xC7, 0xC0, 0xC9, 0xCE, 0xDB, 0xDC, 0xD5, 0xD2,
0xFF, 0xF8, 0xF1, 0xF6, 0xE3, 0xE4, 0xED, 0xEA,
0xB7, 0xB0, 0xB9, 0xBE, 0xAB, 0xAC, 0xA5, 0xA2,
0x8F, 0x88, 0x81, 0x86, 0x93, 0x94, 0x9D, 0x9A,
0x27, 0x20, 0x29, 0x2E, 0x3B, 0x3C, 0x35, 0x32,
0x1F, 0x18, 0x11, 0x16, 0x03, 0x04, 0x0D, 0x0A,
0x57, 0x50, 0x59, 0x5E, 0x4B, 0x4C, 0x45, 0x42,
0x6F, 0x68, 0x61, 0x66, 0x73, 0x74, 0x7D, 0x7A,
0x89, 0x8E, 0x87, 0x80, 0x95, 0x92, 0x9B, 0x9C,
0xB1, 0xB6, 0xBF, 0xB8, 0xAD, 0xAA, 0xA3, 0xA4,
0xF9, 0xFE, 0xF7, 0xF0, 0xE5, 0xE2, 0xEB, 0xEC,
0xC1, 0xC6, 0xCF, 0xC8, 0xDD, 0xDA, 0xD3, 0xD4,
0x69, 0x6E, 0x67, 0x60, 0x75, 0x72, 0x7B, 0x7C,
0x51, 0x56, 0x5F, 0x58, 0x4D, 0x4A, 0x43, 0x44,
0x19, 0x1E, 0x17, 0x10, 0x05, 0x02, 0x0B, 0x0C,
0x21, 0x26, 0x2F, 0x28, 0x3D, 0x3A, 0x33, 0x34,
0x4E, 0x49, 0x40, 0x47, 0x52, 0x55, 0x5C, 0x5B,
0x76, 0x71, 0x78, 0x7F, 0x6A, 0x6D, 0x64, 0x63,
0x3E, 0x39, 0x30, 0x37, 0x22, 0x25, 0x2C, 0x2B,
0x06, 0x01, 0x08, 0x0F, 0x1A, 0x1D, 0x14, 0x13,
0xAE, 0xA9, 0xA0, 0xA7, 0xB2, 0xB5, 0xBC, 0xBB,
0x96, 0x91, 0x98, 0x9F, 0x8A, 0x8D, 0x84, 0x83,
0xDE, 0xD9, 0xD0, 0xD7, 0xC2, 0xC5, 0xCC, 0xCB,
0xE6, 0xE1, 0xE8, 0xEF, 0xFA, 0xFD, 0xF4, 0xF3
};
static uint8_t crc_packet(struct IOPacket *pkt) __attribute__((unused));
static uint8_t
crc_packet(struct IOPacket *pkt)
{
uint8_t *end = (uint8_t *)(&pkt->regs[PKT_COUNT(*pkt)]);
uint8_t *p = (uint8_t *)pkt;
uint8_t c = 0;
while (p < end)
c = crc8_tab[c ^ *(p++)];
return c;
}
