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//! State machine for ITS payload continuous mode
#![allow(non_camel_case_types)]
use self::ITS_Payload_Continuous::IHW_;
use crate::util::*;
/// Types that can be returned as an error from the FSM.
///
/// The first word indicate the best guess made by the FSM
/// e.g. TDH_or_DDW0 could be either TDH or DDW0 but the best guess is TDH
/// The best guess is made based on heurestics.
/// Such as the perceived most likely candidate that could have an ID error,
/// or a word that would be easier to get the FSM back on track based on.
#[derive(Debug, Clone, Copy)]
pub enum AmbigiousError {
/// ID error when both DDW0 or TDH would be a valid word.
TDH_or_DDW0,
/// ID error when a Data word, TDT, or CDW could be valid words.
DW_or_TDT_CDW,
/// ID error when a DDW0, TDH, or IHW could be valid words.
DDW0_or_TDH_IHW,
}
sm! {
// All states have the '_' suffix and events have '_' prefix so they show up as `STATE_BY_EVENT` in the generated code
// The statemachine macro notation goes like this:
// EventName { StateFrom => StateTo }
ITS_Payload_Continuous {
InitialStates { IHW_ } // RDH: stop_bit == 0 && page == 0
// No value is associated with the event
_Next {
c_IHW_ => c_TDH_, // RDH: stop_bit == 0 && page > 0
c_TDH_ => c_DATA_ // TDH continuation bit set
}
_NoDataTrue {
TDH_ => DDW0_or_TDH_or_IHW_,
DDW0_or_TDH_ => DDW0_or_TDH_or_IHW_,
DDW0_or_TDH_or_IHW_ => DDW0_or_TDH_or_IHW_
}
_NoDataFalse {
TDH_ => DATA_,
DDW0_or_TDH_ => DATA_,
DDW0_or_TDH_or_IHW_ => DATA_
}
// end of CDP
_WasDdw0 {
DDW0_ => IHW_,
DDW0_or_TDH_ => IHW_,
DDW0_or_TDH_or_IHW_ => IHW_
}
_WasData {
DATA_ => DATA_,
c_DATA_ => c_DATA_
}
_WasTDTpacketDoneFalse {
// Event Page Should be full (not strictly full to 512 GBT words apparently...)
DATA_ => c_IHW_,
c_DATA_ => c_IHW_
}
_WasTDTpacketDoneTrue {
DATA_ => DDW0_or_TDH_or_IHW_, // If TDH: should have internal trigger set
// If DDW0: RDH: stop_bit == 1 and Page > 0_
// If IHW: Page > 0 && stop_bit == 0
c_DATA_ => DDW0_or_TDH_or_IHW_ // RDH: stop_bit == 1 and Page > 0_
}
_WasIhw {
IHW_ => TDH_,
DDW0_or_TDH_or_IHW_ => TDH_
}
}
}
/// State machine for ITS payload continuous mode.
pub struct ItsPayloadFsmContinuous {
state_machine: ITS_Payload_Continuous::Variant,
}
impl Default for ItsPayloadFsmContinuous {
fn default() -> Self {
Self::new()
}
}
impl ItsPayloadFsmContinuous {
/// Create a new state machine in the initial state.
pub fn new() -> Self {
Self {
state_machine: ITS_Payload_Continuous::Machine::new(IHW_).as_enum(),
}
}
/// Reset the state machine to the initial state.
pub fn reset_fsm(&mut self) {
self.state_machine = ITS_Payload_Continuous::Machine::new(IHW_).as_enum();
}
/// Advance the state machine by one word.
///
/// Takes a slice of 10 bytes representing the GBT word.
/// Returns the type of the word wrapped in an OK if the ID was identified.
/// If the ID could not be determined, a best guess is returned wrapped in an error type to be handled by the caller
pub fn advance(&mut self, gbt_word: &[u8]) -> Result<ItsPayloadWord, AmbigiousError> {
use ITS_Payload_Continuous as event;
use ITS_Payload_Continuous::Variant as state;
let current_state = self.state_machine.clone();
let (next_state, current_word): (state, Result<ItsPayloadWord, AmbigiousError>) =
match current_state {
state::DATA_By_WasData(stm) => match gbt_word[9] {
// All ranges that are legal data word IDs
0x20..=0x28 | 0x40..=0x46 | 0x48..=0x4E | 0x50..=0x56 | 0x58..=0x5E => (
stm.transition(event::_WasData).as_enum(),
Ok(ItsPayloadWord::DataWord),
),
Tdt::ID if !tdt_packet_done(gbt_word) => (
stm.transition(event::_WasTDTpacketDoneFalse).as_enum(),
Ok(ItsPayloadWord::TDT),
),
Tdt::ID if tdt_packet_done(gbt_word) => (
stm.transition(event::_WasTDTpacketDoneTrue).as_enum(),
Ok(ItsPayloadWord::TDT),
),
Cdw::ID => (
stm.transition(event::_WasData).as_enum(),
Ok(ItsPayloadWord::CDW),
),
// Assume data word but return as error
_ => (
stm.transition(event::_WasData).as_enum(),
Err(AmbigiousError::DW_or_TDT_CDW),
),
},
state::DDW0_or_TDH_or_IHW_By_NoDataTrue(stm) => match gbt_word[9] {
Tdh::ID if tdh_no_data(gbt_word) => (
stm.transition(event::_NoDataTrue).as_enum(),
Ok(ItsPayloadWord::TDH_after_packet_done),
),
Tdh::ID if !tdh_no_data(gbt_word) => (
stm.transition(event::_NoDataFalse).as_enum(),
Ok(ItsPayloadWord::TDH_after_packet_done),
),
Ihw::ID => (
stm.transition(event::_WasIhw).as_enum(),
Ok(ItsPayloadWord::IHW),
),
Ddw0::ID => (
stm.transition(event::_WasDdw0).as_enum(),
Ok(ItsPayloadWord::DDW0),
),
// Error in ID, assuming TDH to try to stay on track, but return as error to be handled by caller
_ => (
stm.transition(event::_NoDataFalse).as_enum(),
Err(AmbigiousError::TDH_or_DDW0),
),
},
state::DATA_By_NoDataFalse(stm) => match gbt_word[9] {
// All ranges that are legal data word IDs
0x20..=0x28 | 0x40..=0x46 | 0x48..=0x4E | 0x50..=0x56 | 0x58..=0x5E => (
stm.transition(event::_WasData).as_enum(),
Ok(ItsPayloadWord::DataWord),
),
Tdt::ID if tdt_packet_done(gbt_word) => (
stm.transition(event::_WasTDTpacketDoneTrue).as_enum(),
Ok(ItsPayloadWord::TDT),
),
Tdt::ID if !tdt_packet_done(gbt_word) => (
stm.transition(event::_WasTDTpacketDoneFalse).as_enum(),
Ok(ItsPayloadWord::TDT),
),
Cdw::ID => (
stm.transition(event::_WasData).as_enum(),
Ok(ItsPayloadWord::CDW),
),
// Assume data word but return as error
_ => (
stm.transition(event::_WasData).as_enum(),
Err(AmbigiousError::DW_or_TDT_CDW),
),
},
state::TDH_By_WasIhw(stm) => (
if tdh_no_data(gbt_word) {
stm.transition(event::_NoDataTrue).as_enum()
} else {
stm.transition(event::_NoDataFalse).as_enum()
},
Ok(ItsPayloadWord::TDH),
),
state::c_DATA_By_WasData(stm) => match gbt_word[9] {
// All ranges that are legal data word IDs
0x20..=0x28 | 0x40..=0x46 | 0x48..=0x4E | 0x50..=0x56 | 0x58..=0x5E => (
stm.transition(event::_WasData).as_enum(),
Ok(ItsPayloadWord::DataWord),
),
Tdt::ID if tdt_packet_done(gbt_word) => (
stm.transition(event::_WasTDTpacketDoneTrue).as_enum(),
Ok(ItsPayloadWord::TDT),
),
Tdt::ID if !tdt_packet_done(gbt_word) => (
stm.transition(event::_WasTDTpacketDoneFalse).as_enum(),
Ok(ItsPayloadWord::TDT),
),
Cdw::ID => (
stm.transition(event::_WasData).as_enum(),
Ok(ItsPayloadWord::CDW),
),
// Assume data word but return as error
_ => (
stm.transition(event::_WasData).as_enum(),
Err(AmbigiousError::DW_or_TDT_CDW),
),
},
state::c_DATA_By_Next(stm) => match gbt_word[9] {
// All ranges that are legal data word IDs
0x20..=0x28 | 0x40..=0x46 | 0x48..=0x4E | 0x50..=0x56 | 0x58..=0x5E => (
stm.transition(event::_WasData).as_enum(),
Ok(ItsPayloadWord::DataWord),
),
Tdt::ID if tdt_packet_done(gbt_word) => (
stm.transition(event::_WasTDTpacketDoneTrue).as_enum(),
Ok(ItsPayloadWord::TDT),
),
Tdt::ID if !tdt_packet_done(gbt_word) => (
stm.transition(event::_WasTDTpacketDoneFalse).as_enum(),
Ok(ItsPayloadWord::TDT),
),
Cdw::ID => (
stm.transition(event::_WasData).as_enum(),
Ok(ItsPayloadWord::CDW),
),
// Assume data word but return as error
_ => (
stm.transition(event::_WasData).as_enum(),
Err(AmbigiousError::DW_or_TDT_CDW),
),
},
state::c_TDH_By_Next(stm) => (
stm.transition(event::_Next).as_enum(),
Ok(ItsPayloadWord::TDH_continuation),
),
state::c_IHW_By_WasTDTpacketDoneFalse(stm) => (
stm.transition(event::_Next).as_enum(),
Ok(ItsPayloadWord::IHW_continuation),
),
state::DDW0_or_TDH_or_IHW_By_WasTDTpacketDoneTrue(stm) => match gbt_word[9] {
Tdh::ID if tdh_no_data(gbt_word) => (
stm.transition(event::_NoDataTrue).as_enum(),
Ok(ItsPayloadWord::TDH_after_packet_done),
),
Tdh::ID if !tdh_no_data(gbt_word) => (
stm.transition(event::_NoDataFalse).as_enum(),
Ok(ItsPayloadWord::TDH_after_packet_done),
),
Ihw::ID => (
stm.transition(event::_WasIhw).as_enum(),
Ok(ItsPayloadWord::IHW),
),
Ddw0::ID => (
stm.transition(event::_WasDdw0).as_enum(),
Ok(ItsPayloadWord::DDW0),
),
// Assume DDW0 but return as error
_ => (
stm.transition(event::_WasDdw0).as_enum(),
Err(AmbigiousError::DDW0_or_TDH_IHW),
),
},
state::IHW_By_WasDdw0(stm) => (
stm.transition(event::_WasIhw).as_enum(),
Ok(ItsPayloadWord::IHW),
),
state::InitialIHW_(stm) => (
stm.transition(event::_WasIhw).as_enum(),
Ok(ItsPayloadWord::IHW),
),
};
self.state_machine = next_state;
current_word
}
}