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[07:10:27] <LeoNerd> Offhand does anyone know the difference between the MAX481C and MAX481E ? What's that trailing letter mean? The datasheet isn't too clear on this
[07:11:02] <LeoNerd> Aha.. just as I say that I scroll to the "ordering information" page, where it says the Es are better temperature range
[07:11:17] <LeoNerd> -40 to 85, vs 0 to 70. Either's fine for me
[07:25:55] <LeoNerd> Hrm... ATtiny841-SSU vs ATtiny841-SSUR - what's that trailing R?
[07:26:00] <LeoNerd> They're both SOIC14 package
[07:28:05] <LeoNerd> I don't see any mention under voltage, speed, or temperature range
[07:57:10] <Lambda_Aurigae> LeoNerd, packaging
[07:57:19] <LeoNerd> Ah, reel?
[07:57:20] <Lambda_Aurigae> SSU comes in tubes
[07:57:24] <Lambda_Aurigae> SSUR in reel
[07:57:32] <Lambda_Aurigae> http://www.avrfreaks.net/forum/attiny24a-ssu-vs-attiny24a-ssur?skey=SSUR
[07:57:38] <LeoNerd> Ahah! OK. So it really doesn't matter which to me as I'll be hand-placing
[07:58:18] <Lambda_Aurigae> just had to adjust the search for SSUR on avrfreaks and it popped up.
[07:58:37] <Lambda_Aurigae> looks like that existed in the old style datasheets
[07:58:45] <Lambda_Aurigae> but the new style has dropped a lot of information.
[08:46:45] <twnqx> http://monster6502.com/
[08:52:49] <Lambda_Aurigae> twnqx, that's the,,,4th time I've seen it posted here.
[08:52:51] <Lambda_Aurigae> including mine.
[08:52:53] <Lambda_Aurigae> hehe.
[08:54:22] <twnqx> :D
[10:05:09] <carabia> Who the fuck wants a 6502?
[10:06:06] <carabia> I want a 6581. Oh, lucky me. I've got 3 or 4 of them.
[10:24:25] <carabia> Could use one of the newer revisions too... Can probably find one... "relatively" cheap.
[10:59:33] <twnqx> carabia: send them!
[10:59:41] <twnqx> only have one left :(
[12:08:40] <Lambda_Aurigae> http://survivingtheworld.net/Lesson2840.html
[13:07:55] <antto> any idea why would an atmega freeze quasi-randomly after some time?
[13:09:17] <learath> power?
[13:10:37] <antto> nah.. the atmega is actually placed on an adapter board (with an on-board resonator) and plugged into the actual "mainboard" of the device, into a socket
[13:11:07] <antto> ehm, the device is meant for an atmega162, and this adapter replaces it with an atmega2561
[13:11:37] <antto> i have two of these devices, both run with these modded cpus
[13:11:54] <antto> i swapped the cpus - the problem remains with the device
[13:12:09] <antto> so i think it's somewhere on the board, i don't think it's the 5V
[13:12:53] <antto> today i brought it at work and attached a scope onto the reset circuit (which is part of the mainboard) and left it running, waiting for it to freeze
[13:13:25] <antto> it took a few hours, and it froze.. the reset signal sits high
[13:13:32] <antto> at 5V
[13:18:29] <antto> i was thinking about something maybe jamming the cpu, like interrupts, but i don't have any interrupts on pins, i only got two UART RX interrupts
[13:18:33] * Xark wonders if carabia's 6581 has little LEDs on all the register bits too. :)
[13:19:15] <Xark> antto: What is the software doing?
[13:19:45] <antto> it's a.. complicated musical sequencer for a bassline synthesizer ;P~
[13:20:01] <Xark> antto: Okay, so software "bug" not out of the question. :)
[13:20:36] <antto> but i swapped the cpus and the problem did not teleport onto the other device with this cpu, it remained in this device
[13:21:04] <Xark> But the CPUs are radically different (atmega162 vs 2561)?
[13:21:57] <Xark> E.g., 2561 has extra bits for address lines (since so much flash). This requires software to be specially compiled and takes more code and stack space (etc.)
[13:22:22] <Xark> Also there might be extra interrupt "bug windows" dealing with the PAGESEL reg...
[13:22:28] <antto> hold on
[13:22:49] <antto> the design of the device is for it to work with 162
[13:23:13] <antto> we've made an adapter so we can replace it with a 2561
[13:23:18] <Xark> Well, 2561 and 162 are not fully compatible....I assume you have special software for the 2561?
[13:23:32] <antto> i have two of these devices, and i have two of these cpu adapters
[13:23:38] <antto> so both run with 2561
[13:24:10] <Xark> Okay. I could see if the extra flash is ignored in 2561 some of these issues might be skirted.
[13:24:21] <antto> yes, the thing works, i've written about almost 100kB of "firmware" already
[13:24:52] <antto> this issue recently started to happen with one of the devices
[13:24:59] <Xark> antto: So are you saying you have two of these 2561 devices and one works flawlessly and the other freezes?
[13:25:16] <Xark> (with same firmware)
[13:25:30] <antto> i had analog issues with it too (i stupidly poured nail polish remover on the mainboard which caused all kinds of nasty things)
[13:26:21] <antto> Xark yes, both adapters work, but one of the devices causes the cpu to freeze after some quasi-random time of operation
[13:26:41] <antto> no matter if i swap the two adapters
[13:27:04] <antto> the problem remains with the device, and not with the actual adapter/cpu
[13:28:04] <antto> http://yhype.com/x0xlarge/img/x0xlarge_closeup.jpg <- this is the adapter
[13:28:42] <antto> we put pins on the 40-pin footprint, and we plug that into the 40-pin socket of the 162
[13:30:11] <antto> here it is plugged into the device:
http://i.imgur.com/35ysZM1.jpg
[13:30:19] <Xark> I see. Well, so perhaps some intermittent electrical issue. Sounds like it is not really the CPU from what you say. Does seem challenging to fix (other than "swap the main-board").
[13:32:56] <antto> the problem must be on the mainboard
[13:34:10] <Xark> Maybe not "fully recovered" from nail polish?
[13:35:53] <antto> at first i thought it's the firmware gone corrupted, so i reflashed - nope.. then i thought maybe it's the adapter, so i swapped them - nope, now i thought maybe it's the reset circuit (which is part of the mainboard, they've put a capacitor, some diodes and a logic element to generate the actual RESET signal and feed it into the cpu)
[13:36:57] <antto> i thought it must be going low to cause the cpu to effectively "pause" suddenly, but the reset signal is sitting at 5V and the cpu is frozen
[13:37:20] <antto> i should mention that i failed to actually see the exact moment when it freezes on the scope
[13:37:55] <Xark> Yeah. I can see it might be a real pain to fully diagnose.
[13:37:59] <antto> but, even if there is a spike on the reset signal, but then it goes high again - that would cause it to only restart, right?
[13:38:35] <antto> can you actually make if freeze by just f*cking with the reset signal?
[13:38:43] <antto> * make it
[13:40:43] <Xark> Only holding it low AFAIK.
[13:44:04] <antto> yeah, that's what i know too
[13:45:15] <antto> altho i've managed to accidentally get some pic18s to remain in a weird state while doing naughty things on the reset, even if i leave it high at the end
[13:46:19] <antto> the ASM guy at work explained it to be related to (probably) the reset procedure being incomplete so the program counter doesn't get zeroed or something and the thing probably crashes
[13:46:31] <antto> that's probably a speculation tho
[13:55:29] <Lambda_Aurigae> is your reset held high with an external resistor?
[13:55:59] <antto> no, it's "driven" with a whole little chunk of circuit
[13:56:03] <antto> lemme find it
[13:56:15] <Lambda_Aurigae> so,,,when not driven low,,,,is it held high?
[13:56:47] <antto> http://wiki.openmusiclabs.com/wiki/x0xb0x?action=AttachFile&do=get&target=mainboard2.png
[13:56:58] <antto> the cpu is in the top-left-ish corner
[13:58:01] <antto> i don't fully understand how that works, but in practice it keeps the reset signal low for about 1s after power-on, and then it brings it up to 5V
[13:58:15] <antto> the timing comes from the C105 capacitor
[13:58:53] <Lambda_Aurigae> who the heck put a transistor symbol on the xtal lines?
[13:59:56] <antto> ;]
[13:59:59] <antto> ignore that ;P~
[14:00:14] <antto> probably ladyada
[14:00:24] <antto> when she was young
[14:01:32] <Lambda_Aurigae> seems kinda complex for a reset circuit.
[14:02:01] <Lambda_Aurigae> put a 100K ohm resistor from reset to VCC...put a big cap from reset to GND.
[14:02:23] <Lambda_Aurigae> or....leave the resistor and forget the cap...
[14:02:31] <Lambda_Aurigae> I've never needed a reset delay on anything.
[14:03:27] <Lambda_Aurigae> but, I've seen similar reset circuits before..that looks ok.
[14:04:11] <antto> yeah, this is a design from 2005 or even earlier
[14:04:18] <antto> crap, that's over 10 years old now o_O
[14:04:30] <antto> yep, 2005
[14:04:32] <Lambda_Aurigae> hell, my most used avr programmer is older than that.
[14:04:43] <antto> you're an old h4x0r
[14:04:44] <Lambda_Aurigae> almost 16 years old in fact.
[14:04:53] <Lambda_Aurigae> whatever a h4x0r is..
[14:05:11] <antto> a hackzor ;]
[14:05:28] <Lambda_Aurigae> I'm more of a hacker from the old days.
[14:05:39] <antto> exactly what i meant
[14:05:56] <Lambda_Aurigae> the whole using numbers for letters is not an old thing.
[14:06:05] <Lambda_Aurigae> it's a young thing.
[14:06:11] <Lambda_Aurigae> {:
[14:06:20] <antto> i know
[14:06:36] <Lambda_Aurigae> and annoying as hell as my irc reader horks hairballs on it.
[14:07:31] <antto> so anyway.. the reset circuit remains high yet the cpu is left sitting frozen.. if i reset the power (i got an on/off switch on the back of the device) - the whole thing just boots up normally
[14:07:48] <Lambda_Aurigae> so, time for a jtag debugger.
[14:08:09] <antto> i did not manage to witness the actual moment when the thing freezes on the scope, so no idea if there was an actual spike on the reset signal then
[14:08:12] <antto> oh noes
[14:08:17] <Lambda_Aurigae> and a logic analyzer to watch things like the clock pins and reset and something to watch the VCC and AVCC lines.
[14:08:19] <antto> i don't have a jtag debugger
[14:08:43] <antto> we're not using analog stuff here
[14:09:19] <antto> inputs outputs, SPI, and two UARTs
[14:09:36] <Lambda_Aurigae> and is AVCC tied to VCC then?
[14:10:08] <Lambda_Aurigae> are both GNDs tied to GND?
[14:10:29] <Lambda_Aurigae> I don't see the AVCC pin listed nor the second GND
[14:14:22] <antto> that's all 40 PINs of the atmega162, it doesn't have AVCC i think
[14:14:30] <Lambda_Aurigae> it doesn'
[14:14:36] <Lambda_Aurigae> it doesn't have an ADC?
[14:14:51] <antto> of course, we actually plug an adapter into it's socket with an actual atmega2561, which does have ADCs
[14:15:13] <Lambda_Aurigae> hmm..interesting...older chip.
[14:15:19] <Lambda_Aurigae> no separate AVCC and GND
[14:15:22] <antto> the AVCC on that is connected to 5V
[14:16:02] <antto> both grounds and everything is connected, AGND too
[14:16:43] <Lambda_Aurigae> there are 3 GND pins on the 2561
[14:16:52] <Lambda_Aurigae> and two VCC plus AVCC
[14:17:27] <Lambda_Aurigae> if all that's connected, I have no clue.
[14:18:17] <Lambda_Aurigae> and you have good bypass caps on all VCC/GND pairs close to the chip?
[14:22:06] <Lambda_Aurigae> you could have an overheating problem, bad solder joint, or a ghost.
[14:22:46] <Lambda_Aurigae> or a bad bypass cap.
[14:22:50] <Lambda_Aurigae> or a bad resistor
[14:26:24] <antto> Lambda_Aurigae here's the adapter with the 2561:
http://yhype.com/x0xlarge/img/x0xlarge_closeup.jpg
[14:26:43] <Lambda_Aurigae> bypass caps on the bottom?
[14:27:06] <Lambda_Aurigae> if not,,,,that's a poor design because you really should have those bypass caps.
[14:27:27] <Lambda_Aurigae> I see 1 bypass cap.
[14:27:34] <Lambda_Aurigae> it should have 3.
[14:27:56] <antto> i can't tell right now since i left this thing at work, meh
[14:28:06] <Lambda_Aurigae> it's sitting flat on the desk, so, I would say not.
[14:29:01] <antto> that's a picture from the guy who made these, for illustrative purposes, it doesn't even have the 40-pins soldered
[14:31:56] <antto> i just asked, they are not populated, here is a more current picture:
http://www.rv0.be/sites/default/files/x0xlarge_cutout_0.png?itok=zF_Rt8EM
[14:37:27] <antto> i actually have an earlier model of that adapter, which has a different shape but equivalent connections (same firmware runs on both) which does have the capacitors and inductor, afaict
[14:39:12] <Lambda_Aurigae> so, the problem follows which board?
[14:40:10] <antto> http://i.imgur.com/oRjU8.jpg <- this is it
[14:40:35] <antto> when i swap the two adapters - the problem remains in the device
[14:41:09] <antto> ..it doesn't follow the adapter
[14:41:25] <antto> so the problem must be somewhere on the device
[14:41:36] <antto> yet it causes the cpu to freeze
[14:50:37] <rue_house> do we need to clean out lurkers?
[14:51:04] <rue_house> hah, is that a keyboard controller?
[14:52:40] * Tom_itx sets mode 'lurker' to rue_house
[14:52:53] <rue_house> hah,
[14:53:07] <rue_house> it might be nice to get activity stats for the channels
[14:53:16] <rue_house> does zlog do any of that?
[14:53:21] <Tom_itx> no
[14:54:32] <rue_house> drat
[15:16:32] <Jartza> evening
[15:35:41] <rue_shop3> hey
[19:08:16] <jaggz> anyonw know how I get specs on a board like this?
http://www.amazon.com/WYPH-Digispark-Kickstarter-Attiny85-Development/dp/B00VWVDPNK
[19:08:53] <jaggz> I could just measure it and make a simple version in the computer.. just figured finding an .stl or something would be easier..
[19:09:12] <jaggz> can't even find a seller that links to an information sheet
[19:18:09] <Lambda_Aurigae> what specs do you need?
[19:18:24] <Lambda_Aurigae> attiny85, voltage regulator, v-usb setup, no crystal.
[19:19:51] <Lambda_Aurigae> http://digistump.com/products/1 it is a clone of this.
