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https://opencores.org/ocsvn/zipcpu/zipcpu/trunk
Subversion Repositories zipcpu
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- This comparison shows the changes necessary to convert path
/zipcpu
- from Rev 63 to Rev 64
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Rev 63 → Rev 64
/trunk/rtl/cpudefs.v
110,6 → 110,17
// Be aware, though, it will drop your performance by a factor between 2x and |
// 3x. |
// |
// We can either pipeline our fetches, or issue one fetch at a time. Pipelined |
// fetches are more complicated and therefore use more FPGA resources, while |
// single fetches will cause the CPU to stall for about 5 stalls each |
// instruction cycle, effectively reducing the instruction count per clock to |
// about 0.2. However, the area cost may be worth it. Consider: |
// |
// Slice LUTs ZipSystem ZipCPU |
// Single Fetching 2521 1734 |
// Pipelined fetching 2796 2046 |
// (These numbers may be dated, but should still be representative ...) |
// |
// I recommend only defining this if you "need" to, if area is tight and |
// speed isn't as important. Otherwise, just leave this undefined. |
// |