Only losers text message on cellphones – this guy carries his own teletype for that

Yes, that’s an SMS text messaging device. [Mdziewie] decided that texting on a regular cellphone was too boring and decided to build himself an old-school SMS gateway. Here’s a translated link but the formatting of the forum post gets screwed up with the machine translation.

The device he’s using is an ASR-33 Teletype machine, which was introduced to the market in 1963. It is connected to a GSM modem via an ARM microcontroller, the STM32F103. This chip, along with a few electronic components, let [Mdziewie] design an interface that doesn’t require alteration to the ancient hardware. The forum post linked above includes video of this sending and receiving texts. It’s awesomely loud as it hammers away at the paper, and seems to work as expected.

If you hunger for one of your own but don’t have half-century old equipment there’s still hope. Find yourself a typewriter and turn it into a teletype machine.

SMS gateway lets you Twitter by text message

[GuySoft] threw together a cellphone-based SMS gateway that allows him to push text messages to Twitter. Once up and running, it can be used by multiple people, either with shared or individual Twitter accounts. At its core, this setup uses the cellphone as a tethered modem on a Linux box. The open source software package, Gammu SMSD, provides hardware hooks for phones running in modem mode. The package is already in the Ubuntu repositories but it runs cross-platform and can be downloaded from the project site. This gave [GuySoft] the ability to script a framework that checks for received SMS messages, compares the incoming phone number for a match on a saved list, then pushes the message from a confirmed number to Twitter via their API.

A web interface is used to register new numbers and associate them with Twitter accounts. On the back-end, [GuySoft’s] own Python script handles the translation of the message. You can download all of the code, and get more insight on setup from the readme file, over at the GitHub repository.

SMS controlled irrigation

[Mhkabir] built an irrigation system that communicates by text message. The concept is simple, sending a text message to the system will cause it to switch on the water pump.

Many times we see text message manipulation via the Internet, or using a GSM module. But in this case an inexpensive cellphone is used as the communication interface. The vibration motor has been removed and those connections are monitored to signal incoming messages. Wire leads were soldered to the keypad contacts which allow an Arduino to send out text messages when there is a problem with watering. This isn’t an iron-clad system, as any incoming message will trigger the system and outgoing messages are limited to saved drafts. But a bit of creative programming and we’re sure more functionality could be squeezed out of this hardware.

Keyless entry via SMS

[Billy’s] work got new keys which he didn’t want to carry around with him. Instead he built this system to unlock the door via text message. It is based around a Spinneret Web Server which drives a servo motor. He’s rigged up a pipe hanger to add some leverage to the lock’s knob. We’re surprised that the servo has enough power to do the job here but the video after the break shows there’s really no problem. On the communication side of things [Billy] set up Twilio to wait for text messages from an approved list of senders, then used an HTML form to issue the unlock commands to the webserver.

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Developing a Sega Game Gear flash cartridge

[Gerry O’Brien] tackled his most recent project, designing a flash ROM cartridge for the Sega Game Gear, with great success. Above you can see the test rig he used to reverse engineer the communications between an original ROM chip and the circuit board that it came on. He removed the chip, soldered a ZIF socket to the pads, then used a DIP socket as an adapter for that chip. Connected to each pin is a test lead for a logic analyzer. That’s a heck of a lot of channels to decipher!

It turns out that the cartridges use Integrated Mapping (does anyone have a link explaining this?) so dropping in a flash memory chip is not an option; you need a memory bank controller. [Gerry’s] solution to this issue is twofold: you can etch your own board with a controller chip and ZIF socket for the flash chip, or you can modify a Sega Master System cartridge to use as an adapter board. We’ve got pictures of both methods after the break, as well as his five instructional videos walking us through the fabrication process.

This isn’t [Gerry’s] first time working with flash cartridges. We looked at his work with Game Boy ROMS earlier in the year.

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Cheap and easy SMS via GSM for your MCU

Non acronym version of the title: send and receive text messages via cell phone communication towers using an Arduino or other microcontroller. “We’ve been doing that for years!” you cry, well yes, technically. But [Fincham] lays it outs simply; commercial offerings are expensive and finding a cell phone that uses RS232 now a days is getting difficult, so a new way of doing the same old is necessary. The good news is USB GSM modems are readily available, cheap, and only require a few interface pins to get them talking with an Arduino. In fact, the image above is all you need.

Location tracking with Twitter and Google maps


[Ryan O’Hara] built a location tracker he could use on motorcycle trips. Ostensibly this is to give his wife piece of mind be we think that was an excuse to play with GPS and SMS. To stand up to the trials of the road [Ryan] took his breadboarded prototype to the next level, using a manufactured board and a SparkFun enclosure. Tucked safely away is a PIC 18F25K20 gathering longitude and latitude from a GM862, formatting the info into a Google Maps link, and sending it to the Twitter feed via an SMS message. If you’re not familiar with the GM862, in addition to being a GPS module it can send and receive cellular data on a GSM network.

This is a nice solid hardware platform from which we can envision a couple of other hacks. The feed could be parsed to make a nice map graphic like the webpage for that Twittering Road Bike. It also might be nice to have a d-pad and character LCD to post your own tweets to the feed at the end of the day.