Stream 16-bit Modifier

Create

# Create
await stream.packet.header.modifiers.configure(number=1)

Clear

# Clear
await stream.packet.header.modifiers.clear()

Obtain

Note

Must create modifiers before obtain.

# Obtain
# Must create modifiers before obtain.
modifier = stream.packet.header.modifiers.obtain(idx=0)

Range

Range specification for a packet modifier for a stream header, specifying which values the modifier should take on. This applies only to incrementing and decrementing modifiers; random modifiers always produce every possible bit pattern. The range is specified as three values: mix, step, and max, where max must be equal to min plus a multiple of step. Note that when “decrement” is specified in PS_MODIFIER as the action, the value sequence will begin with the max value instead of the min value and decrement from there: {max, max-1, max-2, …., min, max, max-1…}.

Corresponding CLI command: PS_MODIFIERRANGE

# Range
await modifier.range.set(min_val=0, step=10, max_val=9)

resp = await modifier.range.get()
resp.min_val
resp.max_val
resp.step

Position, Action, Mask

A packet modifier for a stream header. The headers of each packet transmitted for the stream will be varied according to the modifier specification. This command requires two sub-indices, one for the stream and one for the modifier. A modifier is positioned at a fixed place in the header, selects a number of consecutive bits starting from that position, and applies an action to those bits in each packet. Packets can be repeated so that a certain number of identical packets are transmitted before applying the next modification.

Corresponding CLI command: PS_MODIFIER

# Position, Action, Mask
await modifier.specification.set(position=0, mask=Hex("FFFF0000"), action=enums.ModifierAction.INC, repetition=1)
await modifier.specification.set(position=0, mask=Hex("FFFF0000"), action=enums.ModifierAction.DEC, repetition=1)
await modifier.specification.set(position=0, mask=Hex("FFFF0000"), action=enums.ModifierAction.RANDOM, repetition=1)

resp = await modifier.specification.get()
resp.action
resp.mask
resp.position
resp.repetition