Figure 1. Lookup Specifications Parameters
- Lookup Rate
- This is the supported lookup rate of the CAM instance (expressed in million Lookups per second). In order to save resources, it is important not to set the lookup rate higher than required.
- Fixed/Variable Rate
- Enable variable lookup rate. Variable rate uses less RAM
and logic resources for most configurations, but does not guarantee fixed
lookup rate or fixed latency.Note: This parameter is only available for STCAM.
- Lookup Interface Frequency
- This is the clock frequency for the Lookup Request and Response Interfaces, specified in MHz.
- Enable Flow Control
- Enable flow control for the lookup interface output. Flow
control adds extra FIFOs for SINGLE_CLOCK mode, so the lookups can be
stopped. Flow control is not needed if the
m_axis_lkup_treadyport always is high when the lookup response arrives. - Clocking Mode
- Options available in this pull-down menu are: SINGLE CLOCK and DUAL CLOCK.
When SINGLE CLOCK is selected the configuration parameter
RAM Frequencyis not available. - RAM Frequency
- This is the clock frequency for the memories (block RAM/URAM) and the
internal datapath, specified in MHz. Specifying a higher frequency RAM clock
enables time division of the hardware resources, leading to significant
resource savings. This configuration parameter is only available when
CLOCKING_MODE = DUAL_CLOCKis selected.Note: When CLOCKING_MODE = SINGLE CLOCK, RAM_FREQ = LOOKUP_INTERFACE_FREQ.