I'm designing a board with ESP and VS1053 to be used as an internet radio. The main differences with other boards is the wired Ethernet connection, on board Class D amplifier and FM receiver.

There is a project log on Hackaday : https://hackaday.io/project/28422-karadio-wired and the Altium design ...

I think they use an ethernet switch with one RMII interface and two 100BT interface such as KSZ8463RL: http://ww1.microchip.com/downloads/en/DeviceDoc/KSZ8463ML_RL_FML_FRL_ds_1.0.pdf

You have only one interface, but you can daisy chain the controllers which ease the cabling and even if one node is ...

I wrote above, the BLINK_GPIO output frequency only 3Mhz，If the clock is 240 Mhz，I/O output frequency why so low?

May be because the C function gpio_set_level get translated in multiple assembly instructions by the C compiler ?


F.