Ever written a bit of software, looked at it the next day, then not been able to figure out what the hell you were doing?
If I didn’t somehow forget to save after the last compile, it looks to me as if the odd captured data from last night is complete garbage, because I was feeding the SPI data straight into the MAX232. That… I don’t know how I could have gotten that wrong.
What do you do when it is 11pm and you want two pancakes and no mess? Batter Blaster! Sure, I have to work on my pancake cooking ability now, but at least I am able to go to the fridge, get out a spray can of pancake mix, and quickly make up two pancakes.
I think they might be a little sweeter than normal, and they do taste a little flour-y, but they are clearly better than no pancakes.
I ran into some headaches with electronics tonight. First, I tried to get recognizable data out of the Honda Music Link, using most of the hardware mentioned last night. Unfortunately, this didn’t work out as I hoped. While the PIC and NEC-branded IEbus controller communicate via SPI, a Control / Data line is also used. This means that the data I sniff in either direction could either be control or data, and without knowing the state of that line it’ll be even harder to figure out the protocol.
I’m thinking that the best thing to do (if I want to continue the project) is to pick up a PIC with two SPI lines, so I can read both of them into buffers at the same time. Then I can also check the status of C/D, bundle all this together, and easily output it to the PC, already in a somewhat readable format.
Or, I can just stop working on the project again.
After getting frustrated with that, I decided to tear into the Xbox 360 Chatpad (photo gallery retired) and see if I could figure out what it is spitting out. Well, the short answer is that I couldn’t. I was able to see something, but I’m not sure what it is. (Screenshot of data being captured.)
The serial data is 0-2V when coming out of the 360, and it appears to do some regular polling, back and forth. I couldn’t figure out the baud rate and whatnot, so I couldn’t really tell if what I was seeing was valid data or not. That said, it’s a start.
Here’s two more photos:
· Test leads connected to Chatpad.
· Detail of leads soldered to internal Xbox 360 Chatpad connector.
I finally got around to putting together the SPI sniffer I mentioned back on 26-July. The only problem is that I left all the crystals in my cube at work, so I couldn’t give it a test run tonight. I think the software is functional, but I have no good way of being sure yet.
Oh, there is also this photo of the oscilloscope screen showing little blips of data, from when I hooked the scope up to one of the SPI lines, just to be sure that I could see something.
Most of tonight was spent putting together things on the breadboard, making the DB9 cables, making the leads for the micro clips, and writing the interrupt handler (feeds SPI data into the FIFO for writing out via the UART). Hopefully I’ll get more done tomorrow. My hope is that by the end of the Thanksgiving weekend I’m able to understand what is going on between the PIC and IEbus controller, and thusly (hopefully) the rest of the vehicle. From there I will (hopefully) be able to start getting an idea of what actually needs to go into firmware for the HML itself.
[Cross posted to
Today’s beer purchases were:
· Baltika 9 Extra Lager
· Arbor Brewing Company’s Espresso Love
· Wells’ Banana Bread Beer
· Southern Tier’s Pumking (x6)
· JW Lees Manchester Star Ale
· New Holland’s Dragon’s Milk (x2)
· Lindemans’ Framboise Lambic
· Bells’ Special Double Cream Ale
· O’Fallon’s Goat’s Breath Bock Ale
Guess what happens when you mix coffee (Moka), milk, and methylcellulose? You get that. It’s also tasty, but odd… Being from the US I’m conditioned to have slimy, dessert-like things (such as this) taste sweet, but instead it is savory. It tastes just like a slightly starchy cup of cold coffee. Except it’s thick… Very thick… Think personal lube thick, coating the inside of your mouth with coffee goodness.
Next time I think I’ll make it with plain black coffee, just because.
Anyone else noticing a lot of SSH scanning going on?
There just seems to be a whole bunch more lately, with most of it happening overnight. That is, 9pm – 3am EDT, 12am – 7am EDT, etc.
Now that I finally got DenyHosts working properly things seem to be a bit better. (I’d stupidly bolted on to a default hosts.allow which had an ALL : ALL : allow up near the top in the comments, which I didn’t read.)
I’m up to 650-some blocked hosts, and I’m fairly sure there will be another 10 or so today.
Sovtek 7474 ICI wasn’t aware that Sovtek ever made ICs. Then again, it might not be the Sovtek which is so well known for its guitar parts and tubes and whatnot. Beyond that 7474 there (and it’s eight or so peers) I’ve also got a couple of 7410 parts.
So, where did I get them?
Well, my coworker Jeff had, sometime in the mid 90s, attended one of the local ITT Tech schools. As part of this he received a rather large toolcase which he used to store the electronics parts and tools he used. A few weeks back he told me that I could have his old breadboard, which would be quite handy as I’ve started to find my current one a bit cramped at times. Well, instead of giving me just the breadboard, he gave me the entire case full of stuff, including cables, trays of ICs, and a whole bunch of loose parts.
Tonight I spent some time cleaning out the case, throwing out all the loose resistors, electrolytic caps (I’m not stupid enough to keep mid-90s caps), bits of wire which aren’t of the heavy / pre-tinned version designed for breadboard jumpers, plastic bags, and the other hard to identify / low cost / broken parts. What was left over should be quite handy, especially because I’ve had a strong desire to do some things with discreet logic.
These parts include:
· The aforementioned ICs.
· A large handful of ceramic caps.
· Twenty or so mixed inductors.
· Loads of Pomona cables, typically for connecting to multimeters with BNC connections.
· The really nice, large breadboard.
· Lots and lots of ICs, mostly 74 series, ADCs, and opamps, many of brands I’ve never heard of.
· Mixed older optoelectronics.
· Logic probe and pulser.
· Other stuff, which I’m sure I’m forgetting, but looked useful so it wasn’t tossed…
So, this should be pretty neat. I might finally have enough parts laying around to play with doing some things with discreet logic. Now… What? It would be interesting to maybe design a small tabletop analog synth. Maybe something like the PAiA FatMan but easier to build, in a better case, possibly lower cost, and wholly open source. Hmm… After the audio switch, of course, and the (likely) for-pay project that I’m hoping to wrap up soon as well.
That’s the AC ripple from the power supply mentioned here, when connected to a 10 ohm 10% 10W power resistor, sinking ~490mA. The scope is set at 10mV and 5uS per division, probe at 1x, AC mode. In that image it’s being fed about 36VDC. Cutting that in half using only half the power supply (about 18VDC or so) gives this waveform, with marginally less noise.
The way I see that, peak to peak noise is about 50mV, so just about 1%. I think RMS would actually be a good bit lower, but my scope won’t figure that out for me and I think it’d be a lot of work to do it by hand. So, I think this should be an okay design… This is also on a breadboard, and something well laid out actually with a groundplane and all should be even better.
I might head downstairs and pull out the second filter (inductor + capacitor) and see how much more noise it adds, but I’m fairly certain that it’ll be quite substantial.
One thing is for certain, I really could use a better scope. I’m very tempted to just buy a refurb, $547 Tek 1002. However, I think I’d really rather have one of the B models, which adds serial and USB ports for getting data (screenshots, etc) right out of the scope.
There. 5 gallons of unpasturized, unpreserved Rochester Cider Mill cider has been put to ferment. In with the juice is two pounds of honey from Honeyflow Farm in Dryden, MI, two pounds of Domino Dark Brown (Cane) Sugar, and one packet of Lalvin D47 yest.
With an original gravity (density) of 1.082~1.084, this cider will hopefully be around 7% – 8.5% when it is done.
