We can see this effect by changing the baud clock and watching it’s effect on our buffered square waves generated by the example software. Here’s the result of sending a packet of four toggles with a baud clock of 400k – our overall output is toggling at 200kHz. Now to be precise, the actual baud clock used by the FT232 is 16x the number you send to the baud register, but that’s easily taken care of in software. Here we set the baud register to 25000 to get an overall clock of 400kHz.
Fig 3 – 400kHz baud clock (25k) gives 200kHz edges
And here we can see a baud clock of 1MHz (1uS). The number sent to the baud clock was 62,500 and internally multiplied up to 1MHz.
Fig 4 – 1MHz baud clock (62.5k) provides 500kHz square waves.
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