{"product_id":"rs232-gpio-shield-for-raspberry-pi","title":"[Discontinued] RS232\/GPIO Shield for Raspberry Pi","description":"\u003ch5\u003eDESCRIPTION\u003c\/h5\u003e \u003cp\u003e\u003cspan\u003e\u003cstrong\u003e \u003c\/strong\u003e\u003c\/span\u003eThis 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.\u003c\/p\u003e \u003cp\u003e \u003c\/p\u003e \u003cp\u003e\u003cspan\u003e\u003cstrong\u003eTutorial:\u003c\/strong\u003e\u003c\/span\u003e\u003c\/p\u003e \u003cp\u003e\u003cspan\u003e\u003cstrong\u003e\u003c\/strong\u003e\u003c\/span\u003eThe UART on Raspberry Pi is on P1 and shown below:\u003cbr\u003e \u003cbr\u003eThe 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.\u003cbr\u003eThe detailed steps are as following:\u003cbr\u003eWe need to modify two files:  \/boot\/cmdline.txt and \/etc\/inittab.\u003cbr\u003eModify \/boot\/cmdline.txt:\u003cbr\u003eReplace the original content: \u003cbr\u003edwc_otg.lpm_enable=0 console=ttyAMA0,115200 kgdboc=ttyAMA0,115200 console=tty1 root=\/dev\/mmcblk0p2 rootfstype=ext4 elevator=deadline rootwait\u003cbr\u003eWith:\u003cbr\u003edwc_otg.lpm_enable=0 console=tty1 root=\/dev\/mmcblk0p2 rootfstype=ext4 elevator=deadline rootwait\u003cbr\u003e \u003cbr\u003eModify \/etc\/inittab:\u003cbr\u003eComment out the last line of \/etc\/inittab. To comment out, it simply addess a '#'.\u003cbr\u003e \u003cbr\u003e$ sudo vi \/etc\/inittab\u003cbr\u003e#T0:23:respawn:\/sbin\/getty -L ttyAMA0 115200 vt100\u003cbr\u003eSave the changes, and reboot. We will get an UART with baud rate of 115200.\u003c\/p\u003e \u003cp\u003e \u003c\/p\u003e \u003ch5\u003eDOCUMENT\u003c\/h5\u003e \u003cul\u003e \u003cli\u003e\u003cstrong\u003e\u003cspan\u003e\u003ca href=\"http:\/\/linksprite.com\/wiki\/index.php5?title=RS232\/GPIO_Shield_for_Raspberry_Pi\"\u003eSchematics\u003c\/a\u003e\u003c\/span\u003e\u003c\/strong\u003e\u003c\/li\u003e \u003c\/ul\u003e","brand":"SainSmart","offers":[{"title":"Default Title","offer_id":49290296656026,"sku":"101-40-163","price":6.3,"currency_code":"GBP","in_stock":true}],"url":"https:\/\/coretarps.co.uk\/products\/rs232-gpio-shield-for-raspberry-pi","provider":"My Store","version":"1.0","type":"link"}