Serial Port Complete - Latest Microcontroller projects

Using Generic USB Controllers

serial port parameters. The line-coding information travels in the data stage of
the request:

In the SET_CONTROL_LINE_STATE request, the host tells the device how
to set the RS-232 control signals RTS and DTR. Two bits in the request’s
wValue field contain the information:

The SEND_BREAK request requests the device to send an RS-232 break signal
for the number of milliseconds specified in the wValue field of the request. If
wValue = FFFFh, the device should maintain the break signal until receiving
another SEND_BREAK signal with wValue = 0000h.
The GET_COMM_FEATURE, SET_COMM_FEATURE, and
CLEAR_COMM_FEATURE requests can request, set, or clear an
ABSTRACT_STATE data structure used in call management functions and a
COUNTRY_SETTING code. These requests aren’t relevant for generic
COM-port devices.

9  1 
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0 dwDTERate 4 Bit rate (bits per second)

4bCharFormat1Stop bits:

0 = 1 Stop bit

1 = 1.5 Stop bits

2 = 2 Stop bits

5bParityType1Parity:

0 = None

1 = Odd

2 = Even

3 = Mark

4 = Space

6 bDataBits 1 Number of data bits (5, 6, 7, 8, or 16)

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15..2 Reserved. (Set to zero.)

1RTS:

0: de-assert (RS-232 negative voltage)

1: assert (RS-232 positive voltage)

0DTR:

0: de-assert (RS-232 negative voltage)

1: assert (RS-232 positive voltage)