{"id":468,"date":"2015-02-21T01:53:14","date_gmt":"2015-02-21T01:53:14","guid":{"rendered":"http:\/\/itp.fromjia.com\/?p=468"},"modified":"2015-02-21T19:00:52","modified_gmt":"2015-02-21T19:00:52","slug":"hello-world","status":"publish","type":"post","link":"http:\/\/itp.fromjia.com\/?p=468","title":{"rendered":"Hello LED"},"content":{"rendered":"

\"IMG_4801\"<\/a><\/p>\n

The first time I tried using the GSM module to send a text, I made the dumb mistake of not turning on the module. So it worked this time. I used the code that Benedetta had emailed us.
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\"Sending<\/a>

Sending SMS from GSM module.<\/p><\/div><\/p>\n

A modest next step: turn on a LED with a text. For now, I’m able to receive texts by sending them through the GSM module with CoolTerm, but I can’t receive any messages on the GSM module. I’ll need to figure out how to receive a message, match it, then change the LED pin output to HIGH.<\/p>\n

UPDATE:<\/strong><\/p>\n

I attempted again with the white GSM module. I can read SMS with CoolTerm now, but there seems to be a long delay. It takes a few seconds for the messages to show. If I use the command AT+CMGL=”ALL”<\/em>, only the first part of the first message would display correctly. The rest of the messages are in gibberish. I tried changing the delay that follows\u00a0Serial.write(inChar);<\/em> in the code. But this didn’t help.<\/p>\n

\"Reading<\/a>

Reading SMS in CoolTerm.
<\/p><\/div>\n

I also tried to turn the LED on by texting I<\/em>, and turning it off by texting O<\/em>. After about 10 secs of texting I<\/em>, the LED would turn on. But typing O<\/em> did not work. Also if I change the letter in the code from I<\/em> to O<\/em>, the LED would not turn on. Another issue I had was that after testing with my SIM card for a while, I wouldn’t be able to read anymore SMS on that card though I was still able to send SMS out. I had to switch to another SIM card to continue testing and reading SMS.<\/p>\n

This is how it worked when I text “I<\/em>” to turn on the LED:<\/p>\n