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Si5351 Clock Generator test Enter frequency in MHz? 12.34 Set to 12340000 Hz Measured freq. = 12339414 Hz Enter frequency in MHz? 23.45 Set to 23450000 Hz Measured freq. = 23448886 Hz Enter frequency in MHz? 34.56 Set to 34560000 Hz Measured freq. = 34558355 Hz Enter frequency in MHz?
'Si5351 Register map 'Extracted from ClockBuilder output file '#Channel 0 # Output Frequency (MHz) = 67.890000000 '#Channel 1 # Output Frequency (MHz) = 45.670000000 '#Channel 2 # Output Frequency (MHz) = 56.780000000 regmap byte $00,$00,$18,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00 byte $6F,$2F,$4F,$80,$80,$80,$80,$80,$00,$00,$02,$71,$00,$0B,$A0,$00 byte $01,$60,$02,$71,$00,$0E,$4B,$00,$00,$65,$00,$01,$00,$04,$00,$00 byte $00,$00,$11,$D7,$00,$06,$EB,$00,$05,$A3,$00,$01,$00,$04,$00,$00 byte $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00 byte $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00 byte $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00 byte $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00 byte $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00 byte $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00 byte $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00 byte $00,$00,$00,$00,$00,$30,$00,$D2,$60,$60,$00,$C0,$00,$00,$00,$00 byte $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00 byte $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$0D,$00,$00 byte $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00 byte $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$003. "cb_loader.spin"
Comments
I've been testing Si5351 into C8051F850 & EFM8LB1 (CLU) as prescalers, and they seem to work all the way to 200MHz.
I think a Si5351 can push to >225MHz (VcoMAX/4), but I cannot test that yet.
I did find using a Serial-i2c bridge, that above ~ 100MHz, cable length & grounding matters, or the RF clocks can get into the i2c bus, giving confusing operation.
I think this will be really useful for 'redlining' P8x32As, and also P1Vs - clocking them at their max speed before some instruction on the critical path just begins to fail.
It'll be interesting to see what instruction fails first, and whether its the same for all cogs. If one cog fails at a slightly lower frequency than others, that cog can be used in a test mode to control the Si5351 clock generator