This component iterates through a pseudorandom sequence of numbers, which
steps forward to the following number in the sequence each time the clock is
triggered while the component is enabled. Technically speaking, the algorithm
used to compute the pseudorandom sequence is a linear
congruential generator: Starting from a seed
r0, the following number
r1 is the number
(25,214,903,917 r0 + 11)
The next value r2
is computed from r1
using the same computation, and so forth. This sequence is of 48-bit numbers;
the value seen from the component is the low-order bits as configured
by its Data Bits attribute.
Besides the clock input, the component also includes an enable
input, which leads the clock input to be ignored when enable is 0,
and the reset input, which resets the register's value asynchronously
to the initial seed r0.
The initial seed is user-configurable. If it is configured at 0 (which is
the default), then the seed is based on the current time; when instructed
to reset through the reset input, the component starts with the
same seed based on the past time. It acquires a new seed only when the entire
simulation is reset.
- East edge, labeled Q (output, bit width matches Data Bits attribute)
- Outputs the value currently stored by the register.
- West edge, top pin, labeled with a triangle (input, bit width 1)
- Clock: At the instant that this is triggered as specified by the Trigger
attribute, the component steps to the following number in its sequence.
- West edge, bottom pin (input, bit width 1)
- Enable: The component is enabled when this input is disconnected or 1;
but if it is 0, then the clock input is ignored.
- South edge (input, bit width 1)
- Reset: When this is 1, the pseudorandom sequence asynchronously resets to
its initial seed.
- Data Bits
- The bit width of the value emitted by the component.
- The starting value used for the pseudorandom sequence. If this is 0
(the default), then the starting value is based on the time that the current
- Configures how the clock input is interpreted. The value
indicates that the register should update its value at the instant when the
clock rises from 0 to 1. The
falling edge value indicates that it should
update at the instant the clock falls from 1 to 0.
- The text within the label associated with the component.
- Label Font
- The font with which to render the label.
Poke Tool Behavior
Text Tool Behavior
Allows the label associated with the component to be edited.
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