Enum pir_8_emu::isa::instruction::AluOperationShiftOrRotateType

pub enum AluOperationShiftOrRotateType {
    Lsf,
    Asf,
    Rtc,
    Rtw,
}

All shifts can be performed left or right, as designated by the D bit of the instruction.

If D is a 1, the shift is to the left, all bits will move to a higher value, if D is 0, it's a right shift, moving bits to lower values.

There are then four types of shift that can be performed designated by the final two bits of the ALU instruction.

The name should be appended with an L or R for the direction of the shift, left or right respectively.

For all shift operations, the bit shifted out is set into the Carry flag.

TT	Name	Description
00	LSF	Logical shift - a zero is inserted
01	ASF	Arithmetic shift - a zero is inserted for left shift, bit-7 (MSB) is inserted for right shift
10	RTC	Rotate with carry - the Carry flag is inserted (Carry flag value before it is updated is used)
11	RTW	Rotate without carry - the bit shifted out is inserted

An example of a Arithmetic shift right; AXXX XXXB would become AAXX XXXX, with B copied to the Carry bit.

NB: An 'Arithmetic shift left' is the same as performing a 'Logical shift left', they can be used interchangeably, but 'Arithmetic shift left' should be avoided.

Variants

Lsf

Logical shift - a zero is inserted

Asf

Arithmetic shift - a zero is inserted for left shift, bit-8 is inserted for right shift

Rtc

Rotate with carry - the Carry flag is inserted (Carry flag value before it is updated is used)

Rtw

Rotate without carry - the bit shifted out is is inserted

Trait Implementations

impl Clone for AluOperationShiftOrRotateType

fn clone(&self) -> AluOperationShiftOrRotateType

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Copy for AluOperationShiftOrRotateType

impl Debug for AluOperationShiftOrRotateType

fn fmt(&self, f: &mut Formatter) -> Result

Formats the value using the given formatter.

impl Display for AluOperationShiftOrRotateType

fn fmt(&self, f: &mut Formatter) -> Result

Formats the value using the given formatter.

impl Eq for AluOperationShiftOrRotateType

impl Hash for AluOperationShiftOrRotateType

fn hash<__H: Hasher>(&self, state: &mut __H)

Feeds this value into the given [Hasher].

fn hash_slice<H>(data: &[Self], state: &mut H) where
    H: Hasher, 

Feeds a slice of this type into the given [Hasher].

impl Into<u8> for AluOperationShiftOrRotateType

fn into(self) -> u8

Performs the conversion.

impl Ord for AluOperationShiftOrRotateType

fn cmp(&self, other: &AluOperationShiftOrRotateType) -> Ordering

This method returns an Ordering between self and other.

fn max(self, other: Self) -> Self

Compares and returns the maximum of two values.

fn min(self, other: Self) -> Self

Compares and returns the minimum of two values.

fn clamp(self, min: Self, max: Self) -> Self

🔬 This is a nightly-only experimental API. (clamp)

Restrict a value to a certain interval.

impl PartialEq<AluOperationShiftOrRotateType> for AluOperationShiftOrRotateType

fn eq(&self, other: &AluOperationShiftOrRotateType) -> bool

This method tests for self and other values to be equal, and is used by ==.

#[must_use] fn ne(&self, other: &Rhs) -> bool

This method tests for !=.

impl PartialOrd<AluOperationShiftOrRotateType> for AluOperationShiftOrRotateType

fn partial_cmp(&self, other: &AluOperationShiftOrRotateType) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

#[must_use] fn lt(&self, other: &Rhs) -> bool

This method tests less than (for self and other) and is used by the < operator.

#[must_use] fn le(&self, other: &Rhs) -> bool

This method tests less than or equal to (for self and other) and is used by the <= operator.

#[must_use] fn gt(&self, other: &Rhs) -> bool

This method tests greater than (for self and other) and is used by the > operator.

#[must_use] fn ge(&self, other: &Rhs) -> bool

This method tests greater than or equal to (for self and other) and is used by the >= operator.

impl StructuralEq for AluOperationShiftOrRotateType

impl StructuralPartialEq for AluOperationShiftOrRotateType

impl TryFrom<u8> for AluOperationShiftOrRotateType

type Error = ()

The type returned in the event of a conversion error.

fn try_from(raw: u8) -> Result<AluOperationShiftOrRotateType, ()>

Performs the conversion.