Python script lets you monitor multiple serial devices at once

Not knowing what’s going on inside of your electronics projects can make it quite difficult to get the bugs out. [John] was bumping up against this problem when working on wireless communications between several devices. At just about the same time his friend came up with a script with lets you monitor multiple serial devices in one terminal window.

We’re used to using minicom, a Linux package that does the job when working with serial connections of all kinds. But [John] is right, we’re pretty sure you can only connect to one device per minicom instance. But [Jim's] Python serial terminal (available in this git repository) allows you to specify multiple devices as command line arguments. You can even use wildcards to monitor every USB connection. The script then automatically chooses a different color for each device.

The image above is from [John's] wireless project. Even without any other background this shows how easy it is to debug this way rather than tab back and forth between windows which gets confusing very quickly.

iOS terminal debugging tool

This is a simple iOS debugging tool that will take no time to solder together. There’s even a chance that you already have everything you need on hand. The hack simply connects an RS232-to-USB converter to a breakout board for an iPod connector.

The hardware is aimed not at stock iOS systems, but as an aid to those who wish to run alternative operating systems on them. When the OpeniBoot package is run on an iPod Touch or iPhone it enables a serial terminal on pins 12 and 13. The FTDI breakout board takes these as RX and TX and makes them available to your terminal program of choice via USB. Speaking of USB, you may already have noticed the black cable leaving the right side of the image. Using the terminal doesn’t limit your ability to use the device’s USB functions.

Raspy Juice gives you serial ports and servo control

Up next on the continual march of expansion boards for the Raspberry Pi is the Raspy Juice, a board designed to break out the GPIO pins on the Raspberry Pi into servo, serial, and other miscellaneous connections.

The Raspy Juice features an ATMega168A microcontroller connected to the Raspberry Pi as an I2C slave device. Not only does the addition of a microcontroller add analog inputs to the Raspberry Pi, but also RS232 and RS485 serial connections, a real-time clock, and four JST plugs for hobby servos.

Because the Raspberry Pi can be powered from the GPIO header, the creator, [NTT] added a buck regulator so batteries or solar cells can be used to power the Raspberry Pi.

The Raspberry Pi is a terribly awesome robotics platform, but sadly limited by its capability to drive motors and servos natively. The Raspy Juice adds some much-needed capability to the Raspberry Pi, and we can’t wait to see a robot take its first steps with this expansion board.

Adding a serial trigger to a logic analyzer

If you’re attempting to debug a serial bus with a bare-bones logic analyzer, you’re going to have a bad time. Most of the inexpensive analyzers available don’t have a serial pattern trigger, or a way to start recording data after a specific pattern of bits comes down the pipe. [Neil] sent in a great little project that adds a serial trigger to these analyzers, we’ve got to hand it to him for designing such a useful board.

[Neil] designed a small board featuring a CLPD that converts serial data to parallel data. By setting the trigger condition of the logic analyzer to any 24-bit pattern he wants, it’s possible for [Neil] to sniff a serial bus exactly when he wants to.

The circuit is quite minimal, basically just a 100-pin CLPD and a bunch of 0.100″ header pins. It’s a useful tool, and although we couldn’t find the board file to make our own, we’re sure [Neil] will be providing that shortly.

Getting a console and Quake II running on a Raspberry Pi

Those Raspberry Pi boards are flying into the mailboxes of tinkerers all around the globe, so our tip line is currently awash in a deluge of Raspi hacks. Here’s two that came in over the weekend:

First up is [reefab]‘s port of Quake II for the Raspberry Pi. The build is based of Yamagi Quake II and is mostly playable. The Quake III port for the Raspberry Pi is old hat, but we’re happy to relive the pulse-pounding action of Quake II any day.

Next up is [Joonas]‘ take on getting a serial console up and running with the Raspi. The Raspberry Pi has a UART serial console on its 26-pin header, but you can’t just connect those pins to a serial port. To shift the +/- 12V down to the 3.3 Volts the Raspi can understand, [Joonas] used a MAX3232 – the 3.3 Volt version of everyone’s favorite RS-232 transceiver. With a breadboard and a couple of caps, it’s easy to connect your Raspi to a serial console. Neat.

GSM modem means wireless serial connections

By now, most of us have seen have seen one of those GSM to wi-fi hotspot bridges. They’re interesting devices, and being able to carry a small wireless router with you at all times is very handy. Surprisingly, we haven’t seen many builds featuring these portable wireless hotspots, something probably due to the effort in breaking out a serial connection on these devices. The people at Open Electronics decided to build their own small serial-enabled cell phone modem, a boon to someone wanting a serial connection to any place with a cell tower.

The Open Electronics GSM/GPRS/GPS modem includes a header for an FTDI USB serial chip and a GSM module. Plug one into your computer and after a few short commands into a terminal, you’ve got a serial connection to nearly anywhere in the world.

The cost of the setup is a little high – around 80€ or $100 USD – and you probably should buy more than one so you can also receive data. While it is more expensive than the XBee wireless boards we see often, this GSM modem isn’t limited to the 300 foot range of the XBee. We’ll probably see this in a high altitude balloon before too long.

Build your own USB to Serial dongle

[Johan von Konow] found that he was using an FTDI USB-to-Serial chip in a lot of his projects and wanted to have an easy prototyping component on hand to facilitate this. What he came up with is the extremely small USB to serial dongle seen above. The copper fingers are designed to plug into your USB port. And if you’ve got an unused thumb drive (we’ve got a 128mb version that’s been collecting dust for years) it would make a perfect enclosure for the device.

He’s using an FT232BL chip in a LQFP-32 package. That’s got 0.8mm pitch so make sure you’ve got a steady hand, a fine tipped soldering iron, and some solder wick on hand. The 0603 passives might also give you a bit of a run-around during soldering, but all-in-all we think everyone will be able to successfully assemble this with a little bit of practice. The chip is the most expensive component at just under $6. But the good news is that the board is single sided and only needs one jumper wire making for very little drilling and easy home fabrication.

If you’re putting in a parts order, we’d recommend getting doubling the amount of resistors and capacitors. Chances are you’ll drop a few and nary will they be seen again. We also highly recommend looking into [Gerrit's] surface mount component clamp.