1156 - How can I specify what type of PLL is used for a LatticeECP2/M FPGA?
Beginning in version 7.1 of ispLEVER, the user can specify explicitly whether the software will create a GPLL or an SPLL for the LatticeECP2/M when creating the PLL using IPExpress. This is done with a radio style selector button under the Delay Adjust section. The user must be aware that only the GPLL has the Static Delay or Dynamic Delay feature. The software will inform the user if the PLLCAP is required for this PLL when the Calculate button is pushed.
The user must be familiar with the operating parameters of both the GPLL and the SPLL when using this feature. The operating parameters are shown in the
Lattice ECP2/M Data Sheet.
If the user prefers, they can have the software select whether to create a GPLL or SPLL for the PLL they wish to create by selecting the last button in the list. The software will inform the user in the PAR report which type was used and if there is a requirement for the PLLCAP for any of the PLLs.
If you are migrating an design from an older version of software then this choice will not be shown if you open the IPExpress tool to regenerate the existing module. The user should select one option in this case. The software will default to the choice which lets it choose the type to generate if no option is selected.
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