PC hardware to run LinxCNC
Hi Gera,My question was based on your post where you already disabled hyperthreading and already set Isolcpus to 1.
Reread it, I mainly asked if the first jitter latency was no higher than 12656 (you said that's the value you got with it all setup properly with hyperthreading disabled and Isolcpus set to 1), what was the second jitter latency and what values were both of the interval latencies?
Gera
Hmm...that's stretching my memory - and it's only a couple of days
. As far as I can recall, it was slightly less. I'll switch back inot that version of the system, crank it all up and rerun the sniffer. . Following that I hooked up the toroid and got readings from the two combinations of 2ary wires, then hooked one red and the black centre-tap up to the PMDX power board, which gave an output of 80-ish V (I haven't tested the current yet).I can't get the breakout board fired up until I've got the parallel port cable - whichever config I decide on - soldered up. Which, with my soldering "skills", is going to take quite some time.
ELCBs (or RCDs as we call them in the UK) can be rather troublesome. I ended up powering my VFD through a solid-state relay controlled by LinuxCNC. This is deliberately of the type that only turns on at the mains zero-crossing so the surge current into the capacitors is much less.Another note: I have tested the mains swtitch for the drive power train - it didn't blow the socket's fuse into a squillion tiny particles and trip the ELCB this time
Ahem...the reason that the fuse blew and the ELCB/RCD tripped was that the idiot who wired the switch (me) literally got his wires crossedAlexN wrote:
ELCBs (or RCDs as we call them in the UK) can be rather troublesome. I ended up powering my VFD through a solid-state relay controlled by LinuxCNC. This is deliberately of the type that only turns on at the mains zero-crossing so the surge current into the capacitors is much less.Another note: I have tested the mains swtitch for the drive power train - it didn't blow the socket's fuse into a squillion tiny particles and trip the ELCB this time
.Hence making sure that I'd got it right before adding anything else to the chain! And why I'm quadruple-checking the DB25 pinouts - computer and breakout board - in case I do something stupid there too...
AlexN wrote:
but it also has a 90 mm fan (connected to the D525's three-pin chassis fan socket) blowing across one end of it (the mess of cables on the desk has pushed it out of way of the bulk of the sink).
The motherboard has sockets for a fan? I'm curious to know where. Or is it your case that you are talking about?
In btween the large slotted-fin heat sink and the row of potrs at the "back" of the board, there's a three-pin header (mine's a red-brown colour). The big chart that comes with the board (or should have) shows how to install the fan. There's also a pdf manual on the Intel site, and most likely on the disk that also came with the board (although i haven't even taken that disk out of the box, I must confess!).
You need a three pin fan so that the logic on the board can control its speed according to the built-in temperature sensor. Note that this is a fan for - I think - attaching to the case, not the heatsink, but I may be wrong. In any case, that's how I'm going to use it.
I do not know what all these switches are, my CNC is rather going to be simple with 1 main power switch and that's basically it. But if switches are valuable, I'm interested to know of their functions and operation.
I currently have just the one (10A-fused) switch, which I will add some piggy-back spade connectors to to tap off power to the breakout board (240 V in my case) and to the drives (240 V -> 70-80 V via toroid and bridge-rectifier/capacitor board). A second switch for the computer seems to me like a good idea, even though all circuits will be powerered from the same mains line (people can throw rocks at my "logic" should they wish
).I'm not getting my parts until the end of July so it will take quite a while before you see me running a CNC. My idea is based off of diylilcnc.org and I got the same very affordable controller in a kit as they have (hobbycnc.com Pro board package) because they've had excellent experience and can help me if needed.
They also have a LinuxCNC set up file for that hobbycnc.com controller which is nice because it saves some extra hassle.
I'll be interested to browse about on the hobbycnc site.
At the rate I'm going, July will have long gone before I'm up and running. This evening I got a piece of DIN rail cut for the terminal block array, and did a test assembly with a crude but surpisingly effective home-made "jumper" to connect 8+4 jumpers/blocks into a unit of twelve of which there will be two units, one +ve, one -ve (power links to the geckos and other devices fed from the PMDX power board).
AlexN wrote:
ELCBs (or RCDs as we call them in the UK) can be rather troublesome. I ended up powering my VFD through a solid-state relay controlled by LinuxCNC. This is deliberately of the type that only turns on at the mains zero-crossing so the surge current into the capacitors is much less.Another note: I have tested the mains swtitch for the drive power train - it didn't blow the socket's fuse into a squillion tiny particles and trip the ELCB this time
That's something to think about.. I'll browse about for this too. Which for some reason reminds me that I got the wires at one end of a bit of 26 way ribbon cable tinned prior to soldering 'em onto a (used) male D25 connector. The other end gets a 26 way IDC female socket (for the breakout board). As long as I'm consistent with following the standard pinouts (i.e, the locations of pin 1) and those claimed on the BOB itself, things should be OK...