Motorola W24 用户手册
Serial Interfaces
22
Module Hardware Description
May 31, 2008
The W24 primary UART supports baud rates 2400, 4800, 9600, 19200, 38400, 57600, 115200,
230400, as well as the extended high speed rates: 1Mbps, 1.5Mbps and 3Mbps. Auto baud rate
detection is supported for baud rates up to 115200 bps. All flow control handshakes are
supported: hardware, software, or none. Parity bit and Stop bit definitions are also supported. The
UART default port configuration is 8 data bits, 1 stop bit and no parity, with hardware flow
control and auto baud rate detect enabled.
230400, as well as the extended high speed rates: 1Mbps, 1.5Mbps and 3Mbps. Auto baud rate
detection is supported for baud rates up to 115200 bps. All flow control handshakes are
supported: hardware, software, or none. Parity bit and Stop bit definitions are also supported. The
UART default port configuration is 8 data bits, 1 stop bit and no parity, with hardware flow
control and auto baud rate detect enabled.
Primary UART is defined for 3 different HW models: standard, stand alone and JAVA models.
In the standard model, Primary UART is connected directly to W24 processor. 'AT+i' standard
command will be executed by the W24, while 'AT' commands that are for the G24 primary UART
(stacked configuration), will be diverted by the W24 processor to the G24 interface connector,
and will be executed by the G24.
command will be executed by the W24, while 'AT' commands that are for the G24 primary UART
(stacked configuration), will be diverted by the W24 processor to the G24 interface connector,
and will be executed by the G24.
In the JAVA model, where the G24 JAVA model function as W24 Host application, all UART
commands will be diverted to the G24 interface connector (by different HW wiring), and the G24
will execute them.
commands will be diverted to the G24 interface connector (by different HW wiring), and the G24
will execute them.
Important:
The W24 UART will not send data over the serial interface in case the DTR_N
and/or RTS_N input signals are disabled (set high). Therefore, regardless of the
handshake method, it is still required to enable these signals for proper operation, by
asserting them low.
and/or RTS_N input signals are disabled (set high). Therefore, regardless of the
handshake method, it is still required to enable these signals for proper operation, by
asserting them low.
Note:
Add a pull-up resistors (22-100K) on all UART input signals that can be left in an
undefined state (Hi-Z). The resistors should pull to the VREF voltage level.
undefined state (Hi-Z). The resistors should pull to the VREF voltage level.
Secondary UART (UART2)
W24 incorporates Secondary UART interface intended to support G24 UART2 interface, in
stacked configuration. The interface consists of the following pins (see
stacked configuration. The interface consists of the following pins (see
):
The above signals are routed from 70-pin host connector to G24 70-pin connector via W24. They
are not internally connected to W24 circuits. If the W24 will be used as stand alone only, the
above pins should be left open.
are not internally connected to W24 circuits. If the W24 will be used as stand alone only, the
above pins should be left open.
For more details on implementing a secondary interface for use with G24, please refer to the
"Motorola G24 Developer's Guide - Module Hardware Description", PN 6889192V27.
"Motorola G24 Developer's Guide - Module Hardware Description", PN 6889192V27.
Table 2-4: Secondary UART Interface Signals
Pin #
Pin Name
Description
29
RXD2
Receive Data
31
TXD2
Transmit Data
33
RTS2
Request To Send
35
CTS2
Clear To Send