There is no external ROM, so the microntroller access the emulated RAM/ROM and USB/MicroSD at the same time: Direct write from the uSD to the CPC emulated RAM at 3MB/s (For example).
The PicoCPC is clocked at 375Mhz [https://www.cpcwiki.eu/forum/amstrad-cpc-hardware/picocpc/msg248409/#msg248409 Source]366Mhz. So it is not as powerful as the [[RSF3]] clocked at 480Mhz. But it is more powerful than the [[M4 Board]] clocked at 168Mhz. [https://www.spinpoint.org/2015/10/23/cortex-m4-board/ Source]
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