From b0fb86a693db595c7adcd61c4179f0ddb8807c4e Mon Sep 17 00:00:00 2001 From: px4dev Date: Thu, 10 Jan 2013 23:43:03 -0800 Subject: Sketch out the protocol as it will be on top of I2C --- apps/px4io/protocol.h | 106 +++++++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 104 insertions(+), 2 deletions(-) diff --git a/apps/px4io/protocol.h b/apps/px4io/protocol.h index 90236b40c..218ab9030 100644 --- a/apps/px4io/protocol.h +++ b/apps/px4io/protocol.h @@ -31,15 +31,117 @@ * ****************************************************************************/ +#pragma once + /** - * @file PX4FMU <-> PX4IO messaging protocol. + * @file protocol.h + * + * PX4IO I2C 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. + * + * Most pages are readable or writable but not both. + * + * 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. + * + * Note that the implementation of readable pages prefers registers within + * readable pages to be densely packed. Page numbers do not need to be + * packed. + */ + +/* static configuration page */ +#define PX4IO_PAGE_CONFIG 0 +#define PX4IO_P_CONFIG_PROTOCOL_VERSION 0 /* magic numbers TBD */ +#define PX4IO_P_CONFIG_SOFTWARE_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 /* harcoded # of relay outputs */ +#define PX4IO_P_CONFIG_POWERSW_COUNT 9 /* harcoded # of switched power outputs */ + +/* 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_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_PPM (1 << 2) /* PPM input is valid */ +#define PX4IO_P_STATUS_FLAGS_RC_DSM (1 << 3) /* DSM input is valid */ +#define PX4IO_P_STATUS_FLAGS_RC_SBUS (1 << 4) /* 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) /* 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) /* servo current limit was exceeded */ +#define PX4IO_P_STATUS_ALARMS_ACC_CURRENT (1 << 3) /* accessory current limit was exceeded */ +#define PX4IO_P_STATUS_ALARMS_AP_LOST (1 << 4) + +#define PX4IO_P_STATUS_VBATT 4 /* battery voltage in mV */ +#define PX4IO_P_STATUS_TEMPERATURE 5 /* temperature in (units tbd) */ + +/* 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 /* 0..CONFIG_RC_INPUT_COUNT-1 */ + +/* array of scaled RC input values, -10000..10000 */ +#define PX4IO_PAGE_RAW_RC_INPUT 5 /* 0..CONFIG_RC_INPUT_COUNT-1 */ + +/* array of raw ADC values */ +#define PX4IO_PAGE_RAW_ADC_INPUT 6 /* 0..CONFIG_ADC_INPUT_COUNT-1 */ + +/* setup page */ +#define PX4IO_PAGE_SETUP 100 +#define PX4IO_P_SETUP_ARMING 1 /* arming controls */ +#define PX4IO_P_SETUP_ARMING_ARM_OK (1 << 0) /* OK to arm */ +#define PX4IO_P_SETUP_ARMING_MANUAL_OVERRIDE (1 << 1) /* request local override */ + +#define PX4IO_P_SETUP_PWM_RATES 2 /* bitmask, 0 = low rate, 1 = high rate */ + +#define PX4IO_P_SETUP_PWM_LOWRATE 3 /* 'low' PWM frame output rate in Hz */ +#define PX4IO_P_SETUP_PWM_HIGHRATE 4 /* 'high' PWM frame output rate in Hz */ + +#define PX4IO_P_SETUP_RELAYS 5 /* bitmask of relay outputs, 0 = off, 1 = on */ +#define PX4IO_P_SETUP_POWERSW 6 /* bitmask of switched power outputs, 0 = off, 1 = on */ + +/* autopilot control values, -10000..10000 */ +#define PX4IO_PAGE_CONTROLS 101 /* 0..STATUS_CONTROL_COUNT */ + +/* raw text load to the mixer parser - ignores offset */ +#define PX4IO_PAGE_MIXERLOAD 102 + + + +/* + * Old serial PX4FMU <-> PX4IO messaging protocol. * * This initial version of the protocol is very simple; each side transmits a * complete update with each frame. This avoids the sending of many small * messages and the corresponding complexity involved. */ -#pragma once #define PX4IO_CONTROL_CHANNELS 8 #define PX4IO_INPUT_CHANNELS 12 -- cgit v1.2.3