RS232/GPIO Shield for Raspberry Pi V2.0 - Revision history

Qian.zhang: /* Usage */

2015-01-06T01:08:31Z

‎Usage

Qian.zhang: /* Schematics */

2014-11-20T05:24:53Z

‎Schematics

Qian.zhang: Created page with "==Introduction== This is a shield to add a RS232 level shift to the UART of Raspberry Pi. Moreover, it also breakout the rest headers for easy access. [[File:RS232 for RpiV2..."

2014-11-20T03:35:36Z

Created page with "==Introduction== This is a shield to add a RS232 level shift to the UART of Raspberry Pi. Moreover, it also breakout the rest headers for easy access. [[File:RS232 for RpiV2..."

New page

==Introduction==

This is a shield to add a RS232 level shift to the UART of Raspberry Pi. Moreover, it also breakout the rest headers for easy access.

[[File:RS232 for RpiV2.jpg]]

== Schematics ==

==Usage==

The UART on Raspberry Pi is on P1 and shown below:

[[File:RPI UART.png]]

The UART is /dev/ttyAMAO, it defaults to output system log. But if user wants to use this UART to connect to other modules through UART, for example, GPS module, we need to change the configuration.

The detailed steps are as following:

We need to modify two files: /boot/cmdline.txt and /etc/inittab.

Modify /boot/cmdline.txt:

Replace the original content:

dwc_otg.lpm_enable=0 console=ttyAMA0,115200 kgdboc=ttyAMA0,115200 console=tty1 root=/dev/mmcblk0p2 rootfstype=ext4 elevator=deadline rootwait

With:

dwc_otg.lpm_enable=0 console=tty1 root=/dev/mmcblk0p2 rootfstype=ext4 elevator=deadline rootwait

Modify /etc/inittab:

Comment out the last line of /etc/inittab. To comment out, it simply addess a '#'.

$ sudo vi /etc/inittab
#T0:23:respawn:/sbin/getty -L ttyAMA0 115200 vt100

Save the changes, and reboot. We will get an UART with baud rate of 115200.

@@ Line 9: / Line 9: @@
 *[https://s3.amazonaws.com/linksprite/Shields/RS232_RPI/RS232_GPIO_shield+V2.PDF RS232_GPIO_shield_V2_schematic]
-==Usage==
+== Usage ==
 The UART on Raspberry Pi is on P1 and shown below:
@@ Line 42: / Line 42: @@
 Save the changes, and reboot. We will get an UART with baud rate of 115200.

← Older revision		Revision as of 05:24, 20 November 2014
Line 7:		Line 7:
	== Schematics ==		== Schematics ==

		+	*[https://s3.amazonaws.com/linksprite/Shields/RS232_RPI/RS232_GPIO_shield+V2.PDF RS232_GPIO_shield_V2_schematic]

	==Usage==		==Usage==