Has anyone setup the a gumstix to the SSC-32. I’ve been working with the gumstix for some applications and decided to integrate that into my BRAT. The end goal is to integrate the gumstix to the SSC-32 to provide a wireless interface by adding the wifistix expansion board and using the breakout expansion board for the serial output.
The gumstix run on a 3.3V - 5V max power, so I’m setting up a voltage regulator between the SSC-32 VS2 and the gumstix. Once I get everything together I’ll be looking at how to set it up all on the SES Electronic Carrier.
Images and detail to come
We have a Gumstix verdex driving an SSC-32 via a serial line on the console-vx board in our rover, Regis. You can see pictures on this thread if you scroll down to the bottom of the first page.
touretzky
I hope you don’t mind but I’ll be dropping a few questions. I’m currently using the 400 connex processor because right now the wifistix currently only supports the connex motherboard (although good news is that a wifistix version is coming for the verdex motherboard in the near future according to Jack over at gumstix) at which point I will be switching over to that.
I see what looks to be the radioshack adpater plug into the side of the console-vx - are you drawing power through the SSC-32? (looks like a 7.2V battery in the back of the bot). I assume you put on a voltage regulator. I currently have my one netstix 400xm-cf connected to a radioshack 4 AA pack battery box with the radioshack adapter connected on the end. 4 1.2V rechargeables work well for the gumstix - but 7.2 is a bit much, gumstix states anything over 5v and it’s going to be running hot. Would love to see your powering configuration.
I see USB connected onto the console-vx, what is that being used for communication from the PC to the gumstix. You mentioned serial to the SSC-32 - do you have a null modem cable hooked up and tucked up in there - curious as to your serial interface to the SSC-32 if you wouldn’t mind sharing.
I’m trying to set this up for the BRAT, so I’m trying to cut down on the cables - so I am looking at the breakout board putting on some headers and connecting to the SSC-32 similar to the botboard. Not sure exactly how or if this can be done.
Yes, I’m monitoring the gumstix web site myself, anxiously awaiting the release of the wifistix-vx (or whatever they decide to call it). Our original plan was to use a USB WiFi dongle, but I’d much prefer to use their board, since the dongles we’ve played with in my lab haven’t worked all that well.
Yes. Our original design used two batteries: a 6V to drive the servos (VS1 on the SSC-32), and a 7.2 to drive everything else. We feed the 7.2 directly into the Sabertooth to provide power to the motors, and also feed it into a 5V switching regulator to provide power for the SSC-32 (VL) and Gumstix. Unfortunately, this solution is subject to brownouts when we put too much load on the servos or run the motors for more than a few seconds – both the SSC-32 and the Gumstix reset. So we will have to find a better solution. We’ll either run on a tether or have to get a really big battery. Someone on this board suggested a 5000 mAH battery but I haven’t tried to shop for one yet. I don’t want to go to LiPo because those things are dangerous and I don’t want some undergraduate setting fire to my lab.
The USB connection is from the webcam. That’s the big advantage of the verdex over earlier Gumstix boards: it has USB host capability so it can control devices like webcams and dongles. And we were happy to find that the webcam can be powered directly from the verdex USB jack; we had bought a powered USB hub that we were going to attach to the 5V regulator, but found it wasn’t needed (unless we had wanted to add theWiFi dongle).
The Gumstix talks to the SSC-32 over a serial cable. Unfortunately, commercially available serial cables tend to be big and bulky; they won’t fit inside Regis. Just the mini-DIN jack alone is too tall. Se we made our own using 10-wire ribbon cable, a low-profile DB-9 connector, and a mini-DIN8 connector kit. We just threw away most of the kit (i.e., the plastic shell), soldered 3 wires from the ribbon cable to the mini-DIN8 jack, and encased the pins in Jet dental acrylic (available from Lang Dental Mfg. Co.) to provide protection and mechanical support. The result is a very low-profile mini-DIN jack. Works great! The soldering was a pain, though.
Success with the gumstix connection to the SSC-32. I have video posting up on YouTube soon. It was very simple - I am using the gumstix connex 400, wifistix and robostix and have it connected up almost exactly like you would connect the BotBoard. Now the test I have up on YouTube and all I’m doing tonight was to connect up the TX -> RX from gumstix to the SSC-32 to send commands - haven’t tried to get Query data returned RX -> TX on the gumstix to read back from the SSC-32.
Anyway after I test all that out I will fashion a cable, basically 4 header connector on the gumstix to a 3 (or 2 if RX on the gumstix doesn’t work). I set the jumpers on the SSC-32 exactly like on the botboard - May try to see if it works at 115200 baud.
You don’t see it in the video and as I was typing this I got the idea to hook up the power to the robostix which powers the whole gumstix/wifistick/robostix stack from the VS2 out from the SSC-32 - I am using the 6Volt NiHM battery which is perfect for the 5 - 6V range of the Robostix - I guess if I’m building a bigger robot with more powerful servos and I need to bump up to 7.2 V, I’ll need to hook up a voltage regulator or something to drop it down in the Robostix Range.
So as of right now I have a Linux OS/Wifi unit to control my BRAT. I ordered another Electronic mount so I can drill out some holes to mount the gumstix on, the pain is the small 0-80 size bolts and such for the gumstix - when they say waysmall computing they mean it.
Oh here is the video youtube.com/watch?v=dU6oWsOG8Y8
