Posts from — October 2008
So I’ve finally reached 50 published posts, at a rate of about a post every 10 ten days – not bad, considering how busy I’ve been.
I’ve made a small site change – my trac and subversion sites are now on http, not on https.Â Https wasn’t really necessary, and as I plan on making better use of these sites I decided the hassles of secure sites weren’t really worth it.
October 29, 2008 No Comments
I now have three CAN interfaces.Â I plan on doing tests on all three to measure their performance.
The Acacetus (also sold by Grid Connect as the CAN USB Light) is the least expensive ($100).Â It communicates via a virtual COM port.Â So far I’ve used HyperTerm to communicate with it, which doesn’t work well (binary data isn’t intelligible, etc).Â Using a serial library should work better.
The CAN and virtual COM port settings are accessed by resetting the device, and then going through a series of menus.Â The CAN baud rate isn’t set directly; instead you set the various detailed parameters; fortunately, I found a handy table, but I much prefer Ixxat’s approach (pick the baud rate, and then tweak if you want).
So far, it works, but doesn’t seem in the same class as the Peak or Ixxat – it doesn’t feel as well built, and is more limited (e.g. can’t set baud rate remotely).Â It only comes with driver software.
The Peak is a parallel port dongle; I much prefer a USB connection, but I didn’t pay for the Peak.Â It has a keyboard pass-through connector to provide enough power.Â It is sold in the US by Grid Connect and Phytec for $249.Â The Peak USB to CAN is $279, but is worth the extra money.
The Peak interfaces come with PCAN Light driver, and PCANView which is a simple program to send and receive CAN messages.Â The extra cost, advanced driver has some nice features, such as sharing a CAN interface among multiple applications.
Right now, the Peak is handy because I have PCANOpen Magic Lite for it (it was included with the CANOpenIA-XA kit I have), which provides some basic CANOpen functionality.Â It has many restrictions; for example, it only supports CANOpen address 0x40 to 0x4F, so I had to remap my Copley drives to this address range.
The Ixxat USB-to-CAN compact is the most expensive ($335 from CAN Connection).Â It comes with drivers and some helper programs, including one similar to PCANView, but does not include any CANOpen specific software.Â I talked about it in my previous post.
Comment 8/24/2011: I now have a lot more CAN interfaces, including models from Kvaser (PCI and USB), esd electronics (PCI), and Applicom (PCI).Â I really like both the Ixxat USB to CAN compact and Kvaser Leaf Light.Â
October 25, 2008 No Comments
I recently received an impressive blue ESD safe box.Â Inside was theÂ Ixxat USB-to-CAN compact interface which I had ordered from the CAN Connection store.
So why spend the money on the Ixxat when I already have two CAN interfaces?Â Software support.Â I decided I needed a CAN interface which is supported by the manufacturer’s setup and tuning software.
I like USB to CAN interfaces – I do not having to open up my computer to plug cards in (although I do wish USB connectors could lock – it’s very easy for them to become disconnected if I have to move my computer around).Â I’d like an Ethernet to CAN interface even better, but the only semi-affordable ones I know of are the Anagate CAN interfaces (about $300-$450), which are only supported by CANFestival (but not by AMC, Copley, Elmo, etc).
Only Kvaser and Ixxat CAN interfaces are supported by all of the CANOpen servo drives I own (AMC, Copley, Elmo), so I decided to buy either a Ixxat USB-to-CAN compact or a Kvaser Leaf Light.Â I decided to buy the Ixxat because:
- I like the Ixxat physical arrangement better (only the USB cable is permanently attached).
- Kvaser currently does not have a CANFestival driver, which is very important since I plan on using CANFestival.
- Faulhaber and Maxon support Ixxat but not Kvaser.
My Ixxat does have a quality feel to it, and unlike many CAN interfaces, does pack substantial processing power (a 24MHz Infineon C161 with 128K SRAM and 512K flash).Â It is available with either a single RJ45 or single DB9M connector.Â I choose the DB9M version since my other CAN interfaces use DB9M connectors.
Right now I am using the Ixxat with the Copley CMO COM library.Â One quirk – Copley supports Ixxat in their CMO and CML libraries, but not in CME2 (Copley’s setup and tuning application).Â Copley supports Kvaser in all three.
CME2 is needed to setup the drives.Â The CAN baud rate has to be set from CME2, as well as the amplifier settings such as Hall sensor settings.Â However, it’s easy to connect using the Copley’s serial port and a properly wired RJ12 to DB9F cable.
October 25, 2008 8 Comments