Panasonic ENW89841A3KF, Руководство пользователя

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PAN1322-SPP
ENW89841A3KF
User’s Manual 16 Revision 1.3, 2013-08-14
Hardware Description
PAN1322-SPP Interfaces
3 PAN1322-SPP Interfaces
3.1 UART Interface
The UART interface is the main communication interface between the host and PAN1322-SPP. AT commands
are desribed in detail in the AT Commands specification
[1] .
The interface consists of four UART signals and two LPM control signals as shown in Figure 4 .
UARTTXD
UARTRXD
UARTRTS
UARTCTS
WAKEUP_BT
WAKEUP_HOST
UARTTXD
UARTRXD
UARTRTS
UARTCTS
P0.14 input
P0.0 output
Host PAN1322
Figure 4 UART Interface
3.1.1 UART
The lines UARTTXD and UARTRXD are used for commands, responses and data. The lines UARTRTS and
UARTCTS are used for hardware flow control. A separate supply voltage, VDDUART, defines the UART reference
levels to fit any system requirements.
3.1.1.1 Baud Rates
The UART baud rate can be configured with the BD_DATA parameter
UART_Baudrate
. The module is
programmed for a default baudrate of 115200 baud. Reprogramming of the EEPROM configuration is possible by
AT commands at manufacturing time of the end product. The baudrate written to EEPROM will be used each time
PAN1322-SPP starts or, HW or SW reset is done.
The host is also able to change the baudrate temporarily with an AT command. This baudrate is used by
PAN1322-SPP until a HW or SW reset is done, when it will change back to the baudrate stored in the EEPROM.
The supported baud rates are listed in
Table 3 together with the small deviation error that results from the internal
clock generation.
Table 2 UART Baud Rates
Wanted Baud Rate Real Baud Rate Deviation Error (%)
9600 9615 0.16
19200 19230 0.16
38400 38461 0.16
57600 57522 -0.14
115200 115044 -0.14
230400 230088 -0.14
460800 464285 0.76
921600 928571 0.76