HBM DMP41, Описание интерфейса

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Communication with the DMP
USB HOST interface
DMP41
A03474_04_E00_00 HBM: public
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3.2 USB HOST interface
The DMP41 enables connection to a USB HOST interface.
A USB Device (e.g. keyboard) is always connected to a USB HOST
(controller).
The DMP41 can be connected via the USB HOST socket to
S
a USB stick
S
a keyboard
S
an RS232 adapter
3.3 RS‐232 interface
START 0 1 2 3 4 5 6 PARITY STOP
Logic 1
Logic 0
L i
ne level of the Y character with negative logic
A START bit is set before each character (data byte). It is followed by the
data bits and a STOP bit. As the data are transferred serially, the speed of
transmission must match the speed of reception.
The number of bits per second is called the baud rate. The exact baud rate
of the receiver is synchronized with the START bit for each byte transferred.
Next come the data bits, each with the same length. When the STOP bit is
reached, the receiver goes to the wait state, until it is reactivated by the next
START bit.
USB HOST
ETHERNET