User Manual

EHS6 Hardware Interface Overview
2.1 Application Interface
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EHS6_HIO_v01.441 Page 12 of 38 2013-07-11
Confidential / Preliminary
wake up the application from power saving state.
Configured for 8 data bits, no parity and 1 stop bit.
ASC0 can be operated at fixed bit rates from 1,200bps up to 921,600bps.
Autobauding supports bit rates from 1,200bps up to 230,400bps.
Supports RTS0/CTS0 hardware flow control. The hardware hand shake line RTS0 has an
internal pull down resistor causing a low level signal, if the line is not used and open.
Although hardware flow control is recommended, this allows communication by using only
RXD and TXD lines.
Wake up from SLEEP mode by RTS0 activation (high to low transition).
2.1.3 Serial Interface ASC1
Four EHS6 GPIO lines can be configured as ASC1 interface signals to provide a 4-wire unbal-
anced, asynchronous modem interface ASC1 conforming to ITU-T V.24 protocol DCE signal-
ling. The electrical characteristics do not comply with ITU-T V.28. The significant levels are 0V
(for low data bit or active state) and 1.8V (for high data bit or inactive state).
EHS6 is designed for use as a DCE. Based on the conventions for DCE-DTE connections it
communicates with the customer application (DTE) using the following signals:
Port TXD @ application sends data to module’s TXD1 signal line
Port RXD @ application receives data from the module’s RXD1 signal line
Figure 4: Serial interface ASC1
Features
Includes only the data lines TXD1 and RXD1 plus RTS1 and CTS1 for hardware hand-
shake.
On ASC1 no RING line is available.
Configured for 8 data bits, no parity and 1 or 2 stop bits.
ASC1 can be operated at fixed bit rates from 1,200 bps to 921,600 bps.
Autobauding supports bit rates from 1,200bps up to 230,400bps.
Supports RTS1/CTS1 hardware flow. The hardware hand shake line RTS0 has an internal
pull down resistor causing a low level signal, if the line is not used and open. Although hard-
ware flow control is recommended, this allows communication by using only RXD and TXD
lines.