MCS® 51 / MCS® 151 / MCS® 251 Performance Benchmark

The main purpose of this benchmark is to differentiate the architecture performance of MCS51, MCS151 and MCS251 using 2 different code. Internal and External code execution were compared. Page and Non-Page mode comparison were considered too.

MCS 51

Performance Evaluation were executed using 87C51FB. Evaluation were performed at 16Mhz, 20Mhz and 24 Mhz. using MCS 51 binary mode and instruction. All results were referenced to 16 Mhz 87C51FB. 33Mhz results are best case estimation.

MCS 151

Performance Evaluation were executed using 87C151SB. 2 memory configurations and page mode were evaluated at 16Mhz using MCS 51 instruction.

MCS 251

Performance Evaluation were executed using 87C251SB. 2 memory configurations and page mode were evaluated at 16Mhz. using mixture of MCS 251 and MCS 51 source mode and instruction

Two evaluation were performed and results are shown in Figure 1 and Figure 2

Conclusion

Clear performance advantage of MCS 251 and MCS 151 over the MCS 51 even at high clock speed were established. The MCS 151 with its pipelining architecture and page mode capability delivers significant performance increase of up to 5X running internal code. The MCS 251 with its enhance register based CPU and ultra efficient instruction set has consistently out perform the rest. From the evaluation a record of up to 18.24X were achieved in source mode and running internal code. When running external code Page mode provide very significant performance boost. The evaluation described in Figure 2, produce a 45% code reduction using MCS 251 instruction compared to pure MCS 51 instruction.

Note

This benchmark should be used as a guidance only as performance may vary with the contents and structure of the code . Code reduction is dependable on the type of instruction used.