Specifications

PLS63-W Hardware Interface Overview
2.1 Application Interface
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While a USB connection is active, the module will never switch to SLEEP mode. Only if the USB
interface is in Suspend mode, the module is able to switch to SLEEP mode.
2.1.2 Serial Interface ASC0
PLS63-W offers an 8-wire unbalanced, asynchronous modem interface ASC0 conforming to
ITU-T V.24 protocol DCE signaling. 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). For electrical characteristics please refer to Table 3.
PLS63-W 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 the module’s TXD0 signal line
• Port RXD @ application receives data from the module’s RXD0 signal line
Figure 3: Serial interface ASC0
Features:
• Includes the data lines TXD0 and RXD0, the status lines RTS0 and CTS0 and, in addition,
the modem control lines DTR0, DSR0, DCD0 and RING0.
• The RING0 signal serves to indicate incoming calls and other types of URCs (Unsolicited
Result Code). It can also be used to send pulses to the host application, for example to
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 300bps up to 921600bps.
• 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.
Note: The ASC0 modem control lines DTR0, DCD0, DSR0 and RING0 can also be configured
as GPIO lines. If configured as GPIO lines, these GPIO lines are assigned as follows:
GPIO1-->DTR0
GPIO2-->DCD0
GPIO3-->DSR0
GPIO24-->RING0