View source for AOM-DB3500 UART RS232（DEBUG、COM1）


=== '''UART''' ===

User Debian/Linux UART/serial port access is through the tty-devices. The ttydevices have different names depending on UART drivers for different boards.

{| border="1" cellpadding="1" cellspacing="1" style="width: 500px;"
|-
| '''Device Node'''
| '''COM Port Name'''
|-
| /dev/ttyFIQ0
| Debug
|-
| /dev/ttyS0
| COM1（COM1_2 connnector&nbsp; RS232 2-wire）
|-
| /dev/ttyS6
| M.2_E1（UART）
|}

=== '''DEBUG Port Connection''' ===

'''1.Connect the debug port cable on AOM-DB3500.'''

'''2.Connect it to your PC with a USB to COM Cable.'''

{| border="1" cellpadding="1" cellspacing="1" style="width: 280px;"
|-
| colspan="2" style="width: 270px;" | '''DEBUG Pin Connector'''
|-
| style="width: 95px;" | '''Pin'''
| style="width: 169px;" | '''Signal'''
|-
| style="width: 95px;" | 1
| style="width: 169px;" | NC
|-
| style="width: 95px;" | 2
| style="width: 169px;" | RX_DEBUG
|-
| style="width: 95px;" | 3
| style="width: 169px;" | TX_DEBUG
|-
| style="width: 95px;" | 4
| style="width: 169px;" | NC
|-
| style="width: 95px;" | 5
| style="width: 169px;" | GND
|-
| style="width: 95px;" | 6
| style="width: 169px;" | NC
|-
| style="width: 95px;" | 7
| style="width: 169px;" | RTS#
|-
| style="width: 95px;" | 8
| style="width: 169px;" | CTS#
|-
| style="width: 95px;" | 9
| style="width: 169px;" | NC
|}

=== '''Debug Port Settings''' ===

AOM-3821 can communicate with a host server using serial cables. Common serial&nbsp;communication programs such as HyperTerminal, Tera Term, or PuTTY can be used&nbsp;in this case. The example below describes the serial terminal setup using HyperTerminal on a Windows host:<br/> 1. Connect AOM-3821 with your PC using a serial cable.<br/> 2. Open HyperTerminal on your Windows PC, and select the settings demonstrated in the photo below.<br/> 3. Insert a power adapter into the DC jack and power up the board. The Debug&nbsp;&nbsp;console log will be displayed on the terminal screen.

[[File:AOM-DB3500 DEBUG.png|RTENOTITLE]]

=== '''COM1_2——COM1''' ===

[[File:AOM-DB3500 COM1 2.png|600x500px|AOM-DB3500 COM1 2.png]]&nbsp;[[File:AOM-DB3500 COM1 2 Pin header.png|RTENOTITLE]]

{| border="1" cellpadding="1" cellspacing="1" style="width: 500px;"
|-
| colspan="4" | '''COM1_2 Connector,COM1 RS232 Mode Pin Definition'''
|-
| '''Pin'''
| '''Signal'''
| '''I/O'''
| '''Description'''
|-
| 1
| N/A
| &nbsp;
| Not Applicable
|-
| 2
| N/A
| &nbsp;
| Not Applicable
|-
| 3
| COM1_RX_485+
| O
| COM1 RS232 Receive Data
|-
| 4
| COM1_RTS#
| I
| COM1 Request to Send
|-
| 5
| COM1_TXD_422-
| I
| COM1 RS232 Transmit Data
|-
| 6
| COM1_CTS#
| O
| COM1 Clear to Send
|-
| 7
| N/A
| &nbsp;
| Not Applicable
|-
| 8
| N/A
| &nbsp;
| Not Applicable
|-
| 9
| GND
| &nbsp;
| Ground
|-
| 10
| GND
| &nbsp;
| Ground
|-
| 11
| N/A
| &nbsp;
| Not Applicable
|-
| 12
| N/A
| &nbsp;
| Not Applicable
|-
| 13
| COM2_RX_485+
| O
| COM2 RS232 Receive Data
|-
| 14
| COM2_RTS#
| I
| COM2 Request to Send
|-
| 15
| COM2_TXD_422-
| I
| COM2 RS232 Transmit Data
|-
| 16
| COM2_CTS#
| O
| COM2 Clear to Send
|-
| 17
| N/A
| &nbsp;
| Not Applicable
|-
| 18
| N/A
| &nbsp;
| Not Applicable
|-
| 19
| GND
| &nbsp;
| Ground
|-
| 20
| GND
| &nbsp;
| Ground
|}

=== '''Configure Parameters''' ===

Use “stty” command to configure serial port parameters. The commonly used parameters include “Baud rate”, “Data bits”, “Stop bits”, “Parity”, “Flow control”.

See details of the usage of “stty”:
<pre># stty --help
… …
csN set character size to N bits, N in [5..8]
[-]cstopb use two stop bits per character (one with '-')
[-]parenb generate parity bit in output and expect parity bit in input
[-]crtscts enable RTS/CTS handshaking
…</pre>

For example, set COM1<br/> “Baud rate” to 115200<br/> “Data bits” to 8<br/> “Stop bits” to 1<br/> “Parity” to None<br/> “Flow control” to None
<pre># stty -F /dev/ttyS0 115200 cs8 -parenb -cstopb</pre>

=== '''Send and receive data''' ===

Taking COM1 as receiver or sender (An external COM is required to do the sendingor&nbsp;receiving). For example, AOM-3821 is responsible for receiving and inputting instructions. The PC computer is connected via a cable and COM1. The PC computer uses&nbsp;the PuTTY serial port tool, opens the COM port, configures the baud rate to 115200,&nbsp;data bits to 8, stop bits to 1, parity to none, flow control to none, and sends "pass" to&nbsp;the serial port assistant. If no error, the external COM receiver will receive “pass”.&nbsp;
<pre># #---- COM1 as receiver ----# #
# stty -F /dev/ttyS0 115200 cs8 -cstopb -parenb
# cat /dev/ttyS0 &</pre>
<pre># #---- COM1 as sender ----# #
# stty -F /dev/ttyS0 115200 cs8 -cstopb -parenb
# echo pass > /dev/ttyS0
# #----If no error, the external COM receiver will receive “pass”----# #
pass</pre>

Note!

1.Receiver should run before sender.<br/> 2.The "serial port parameters" should be the same for sender and&nbsp;&nbsp;receiver.