National Semiconductor LMX9838DONGLE, Руководство пользователя по оборудованию

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9.0 Board components and Pin As-
signments
A summary of the configuration and selection jumpers is
provided in the tables that follow. Reference both the sche-
matic and PCB layout (included on the CD in the kit)
Table 1. Major Components List
Device Description
U1
National LMX9838 Serial Port Module - Refer-
ence the device datasheet.
U3
National LP3985 Low-Dropout Voltage Regula-
tor
U2
Maxim MAX3225 1 Mbps High Speed UART
Driver
Table 2 Connectors Summary
Connector Description Details
J7 Battery Connector
2mm pitch Maximum input volt-
age is 6V
J6 DC jack Same as above
J8 DP9 serial connec-
tor (male) See Table 5
J5 External processor
interface See Table 6
J4 Advance Audio
interface See Table 7
Table 3 Jumper and Test Point Summary
Jumper /
Test Point
Description Details
J1, J2 and
J3 Clock & UART set-
ting jumper See Table 8
Table 4 Switch and LEDs
Switch/LED Description
S1 Reset button
D1 Operation Status
D2 Data Traffic (TX/RX)
Table 5 J8 DP9 (male) Pin Assignments
Pin # Signal name Description
1 NC No connection
2 RxD Receive Data (input)
3 TxD Transmit Data (output)
4 NC No connection
5 GND Ground
6 NC No connection
7 RTS Ready to send (output)
8 CTS Clear to send (input)
9 NC No connection
Table 6 J5 External Processor Interface
Pin # Signal name Description
1 POWER_D# ON/OFF control of LMX9838
2 VCC LDO output (3.3V)
3 GND Ground
4 TXD Transmit Data (output)
5 CTS# Clear to send (input)
6 RXD Receive Data (input)
7 RTS# Ready to send (output)
8 VCC_CORE
_IN 1.8V voltage regulator input/out-
put
9 RESET# Reset (input)
Table 7 J4
Advance Audio Interface
Pin # Signal name Description
1 VCC
LDO output (3.3V)
2 SCLK
Advanced Audio Interface Clock
3 STD
Advanced Audio Interface
Transmit Data
4 SFS
Advanced Audio Interface Frame
Synchronization
5 SRD
Advanced Audio Interface
Receive Data
6 GND
Ground
Table 8 UART interface setting
J2 J3 J1 UART baud rate
Short Short Short 921600bps
Short Open Short 115200bps(default)
Open Short Short 9600bps
Open Open Short NVS (Default 9600bps)