Hardware Development Guide of Module Product
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4-wire or 2-wire mode can be used for connection. The module interface PWL is
1.8V. If it does not match the PWL of AP interface, it is recommended to add the
PWL conversion circuit.
The connection of ZM5202 UART port and standard RS-232-C interface can be
through the chip like class 232. The design involves the transformation of TTL level
and EIA level. We recommend to use the chip of NLSX5014MUTAG. If using the
2-byte serial bus interface, MAX3232 is recommended, and if using the 8-byte serial
bus interface, SP3238 or MAX3238 is recommended. The connection mode is as
shown in Figure 3-7
Figure 3-7 Module Serial Port & AP Application Processor
ZM5202
AP
RXD
RXD
TXD
TXD
CTS
RFR
CTS
RFR
DTR
DSR
DSR
DTR
DCD
RI
RI
DCD
GND
GND
Figure 3-8 The connection of ZM5202 UART and Standard RS-232-C interface
TTL-
RS232
level
translator
SP3238
MAX3238
ZM5202
module
1.8V
-TTL
level
translator
NLSX5014MUTAG
UART_DCD
UART_DSR
UART_TXD
UART_CTS
UART_RXD
UART_RFR
UART_DTR
UART_RI
GND
RS232_DCD
RS232_DSR
RS232_TXD
RS232_CTS
RS232_RXD
RS232_RTS
RS232_DTR
RS232_RI
GND
1
2
3
4
5
6
7
8
9
User Board
Female DB9
Note:UART_RFR is equal to UART_RTS.