Freescale Semiconductor 56852, Руководство пользователя

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DSP56852EVM User Manual, Rev. 3
2-6 Freescale Semiconductor
2.4 RS-232 Serial Communications
The 56852EVM provides an RS-232 interface by the use of an RS-232 level converter, (Maxim
MAX3245EEAI, designated as U6). Refer to the RS-232 schematic diagram in
Figure 2-4
. The
RS-232 level converter transitions the SCI UART’s +3.3V signal levels to RS-232-compatible
signal levels and connects to the host’s serial port via connector P6. Flow control is not provided,
but could be implemented using uncommitted GPIO signals. The pinout of connector P6 is listed
in
Table 2-2
. The RS-232 level converter/transceiver can be disabled by placing a jumper at JG8.
56852
RS-232
Level Converter
Interface
TXD
RXD
R1in
T1out T1in
R1out
FORCEOFF
JG8
1
2
6
3
2
7
8
4
5
x
1
9
+3.3V
Jumper Removed:
Enable RS-232
Jumper Pin 1-2:
Disable RS-232
P6
Figure 2-4. Schematic Diagram of the RS-232 Interface
Table 2-2. RS-232 Serial Connector Description
P6
Pin # Signal Pin # Signal
1 Jumper to 6 & 4 6 Jumper to 1 & 4
2 TXD 7 Jumper to 8
3 RXD 8 Jumper to 7
4 Jumper to 1 & 6 9 N/C
5 GND
.