I want to use the RTS and DTR lines as general purpose output lines that I can use to reprogram my device.

When the CP2102 is first connected to a PC these lines are logic 1.

When the VCP is opened, they fall to logic 0.

Is there a way to avoid having them go to logic 0.

The USBExpress literature seems to indicate that there is through the SI_HELD_INACTIVE option

Thank You,

Chris Jones

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I would like to use the modem control signals of the CP2102, RTS and DTR, to reprogram the flash memory of my device.
When I open a COM port with the VCP driver, the RTS and DTR signals go active low.
I want to disable this behavior for the driver.

The USB Express development kit has a function SI_SetFlowControl that allows the control lines to be held in active with the value "SI_HELD_INACTIVE".

Does this capabilities exist in the VCP driver?

This is the default behavior of a real com port. There is currently no way to disable this feature in the VCP driver.