Bruce Tomlin Posted October 5, 2005 Share Posted October 5, 2005 Pin 1 is the 5V line, and pin 24 (I believe) is the ground line. Just solder a 22ohm reisistor to pin 1, then solder the positive to the LED to the resistor and the negative to ground. That's it.22 ohms? Are you sure about that? 220 would be more like it. For what it's worth, back in the day I accidentally connected an LED directly to +5 volts, only to have the top immediately explode off and fly directly at my eye. Good thing I wear glasses. I blew another LED some time later, and that time it didn't hit me. But the lesson is clear: LEDs require proper current limiting. Anyhow, R=E/I, I=17ma, E=2.6V (approx for a TTL compatible output) So I wouldn't use a resistor of less than 150 ohms with a TTL compatible output, or about 270 with a full 5 volts. (I just had a vision of a row of LEDs wired up to a nailbox with a +5 volts wire in hand ready to blow them in sequence. Don't try that at home, kiddies.) Quote Link to comment Share on other sites More sharing options...
supercat Posted October 5, 2005 Share Posted October 5, 2005 22 ohms? Are you sure about that? 220 would be more like it. Typical red, orange, yellow, or green LEDs have a voltage drop between 1.7 volts and 2.4 volts, usually around 2 volts. A 220 ohm resistor will thus be a reasonable choice, letting through somewhere between 12-15mA. Blue LEDs have a higher forward voltage drop, however, which may range anywhere from 3.3 volts up to 5 volts or even more. The only way to choose a good resistor is to check the data sheet. If a particular LED has a 4.7 volt drop, a 22 ohm resistor would let through 13mA (not terribly high, but probably adequate). If the LED has a 3.5 volt drop, that same resistor would let through 68mA (likely enough to cause damage). To determine the resistor value to use, check the data sheet for recommended forward current (If) and the forward voltage drop at that current (Vf). Subtract Vf (in volts) from five volts, divide that by the desired current (in mA), and that will be the result (in Kohms). Multiply by 1000 to convert to ohms. For example, an LED with a Vf of 3.5V and an If of 20mA. Subtract 3.5V from 5V, yielding 1.5V. Divide that by 20mA yielding 0.075Kohms. Multiply by 1,000 and the result is 75 ohms. Quote Link to comment Share on other sites More sharing options...
Bruce Tomlin Posted October 5, 2005 Share Posted October 5, 2005 (edited) Blue LEDs have a higher forward voltage drop, however, which may range anywhere from 3.3 volts up to 5 volts or even more.Wow. I hadn't thought about the forward voltage drop because I didn't realize it could be so high. I remember that silicon diodes have (IIRC) an 0.9 volt drop, and germanimum have 0.6, but it had never occured to me that LEDs could have significantly higher voltage drops. In that case, it would probably be prudent to specifically mention that such a low resistance is only for blue LEDs. Because if someone tried that with a red or green LED... =>!POP!<= The danger of eye damage is enough to be aware of what you're doing when you use such a low resistance with an LED. EDIT: and now I'm getting strange ideas of using LEDs as custom voltage drops for low-current applications. Edited October 5, 2005 by Bruce Tomlin Quote Link to comment Share on other sites More sharing options...
supercat Posted October 5, 2005 Share Posted October 5, 2005 In that case, it would probably be prudent to specifically mention that such a low resistance is only for blue LEDs. Because if someone tried that with a red or green LED... =>!POP!<= The danger of eye damage is enough to be aware of what you're doing when you use such a low resistance with an LED. A 22 ohm resistor would let through enough current to permanently damage a red or green LED, but not enough to violently explode it. The maximum power available to the LED through 22 ohms would be just over a quarter watt. Nonetheless, I agree that the 22 ohm resistance should warn that it's only for LEDs with a voltage drop of 4.5 volts or higher, and it's important to check data sheets. EDIT: and now I'm getting strange ideas of using LEDs as custom voltage drops for low-current applications. 942852[/snapback] They're vaguely usable, but really not very good. An ordinary epoxy-cased PN diode will generally have a pretty stable voltage drop. LED voltage drops can vary from one batch to another, and can also vary significantly with temperature, ambient light, current, time, phase of the moon, etc. For some low-precision applications they can be okay (e.g. if you need an opto-coupled on/off current sensor for a device which will draw 10-30mA, you can use an LED to clamp the voltage feeding the optocoupler and also provide visual indication of its status). Generally, though, there are better ways to get voltages. BTW, if you want consistent performance from blue LEDs in a +5-powered device, it's probably best to drive them with a regulated current source. Such a thing would be overkill for making a game cartridge light up but if uniformity of brightness it at all important (e.g. if you have multiple blue LED indicators on a device and want them to match) a current source may be the way to go. Quote Link to comment Share on other sites More sharing options...
neotokeo2001 Posted October 9, 2005 Author Share Posted October 9, 2005 There is one copy of TRONMAN! left. It is a reserve that was cancelled. This is the last one that I will be offering. http://www.atariage.com/forums/index.php?showtopic=77429 END OF LINE.... Quote Link to comment Share on other sites More sharing options...
jmaynard Posted October 10, 2005 Share Posted October 10, 2005 Just as an update, I'm still too exhausted from the weekend to get any pictures up. I will need to downrez 'em a bit in photoshop before posting too (maybe down to 1024x768). Hopefully Jay got the CD-R I burned (he had left for dinner and I found someone who could probably pass it on to him afterward). 941695[/snapback] No, I didn't, Bruce...who did you leave it with? Perhaps I can catch up with them online and get them to send it to me. Quote Link to comment Share on other sites More sharing options...
Bruce Tomlin Posted October 10, 2005 Share Posted October 10, 2005 Drat. I left it with Chase. Oh well. And if all else fails, I can just get the stuff where it can be downloaded. It was just a complete dump of all the pictures I took during Linucon, about 260 megs, of which 60 were the AVI files of those two guys singing. Quote Link to comment Share on other sites More sharing options...
Mayhem Posted October 10, 2005 Share Posted October 10, 2005 Still no sign of my copy here just yet Quote Link to comment Share on other sites More sharing options...
jmaynard Posted October 10, 2005 Share Posted October 10, 2005 Drat. I left it with Chase. Oh well. You should know better than to expect a con chair to remember anything... And if all else fails, I can just get the stuff where it can be downloaded. It was just a complete dump of all the pictures I took during Linucon, about 260 megs, of which 60 were the AVI files of those two guys singing. 945514[/snapback] That'll work, if I can't get the CD. I'll see if I can hunt up Chase and see if he still has it, and if not, I'll let you know. Thanks. Quote Link to comment Share on other sites More sharing options...
Mayhem Posted October 20, 2005 Share Posted October 20, 2005 Anyone still not got their copy yet? No sign still here of it... Quote Link to comment Share on other sites More sharing options...
neotokeo2001 Posted October 23, 2005 Author Share Posted October 23, 2005 Anyone still not got their copy yet? No sign still here of it... 951680[/snapback] Anyone else that has not recieved their copy of TRONMAN!? I will probably be out of touch for this week but I will follow up on it when I get a chance. Quote Link to comment Share on other sites More sharing options...
Mayhem Posted October 24, 2005 Share Posted October 24, 2005 I can only think, assuming you sent it off okay, that apart from it being lost in the mail, is that it's travelling surface instead of air across to me. When did you post it btw? Surface would take 4-6 weeks to reach UK. Quote Link to comment Share on other sites More sharing options...
Necron99 Posted October 25, 2005 Share Posted October 25, 2005 Anyone still not got their copy yet? No sign still here of it... 951680[/snapback] Anyone else that has not recieved their copy of TRONMAN!? I will probably be out of touch for this week but I will follow up on it when I get a chance. 952937[/snapback] I still haven't gotten mine yet either Quote Link to comment Share on other sites More sharing options...
Atari Charles Posted November 2, 2005 Share Posted November 2, 2005 I haven't recieved TronMan yet. I am thinking that packages from the States could be held up in Canada Customs. I've been out of town for a few weeks but have had a friend dilegently check my mail. I look forward to recieving it as it will be cool game to play on my Atari. Charles Quote Link to comment Share on other sites More sharing options...
Albert Posted November 2, 2005 Share Posted November 2, 2005 I haven't recieved TronMan yet. I am thinking that packages from the States could be held up in Canada Customs. I've been out of town for a few weeks but have had a friend dilegently check my mail. I look forward to recieving it as it will be cool game to play on my Atari. Charles 958733[/snapback] My experience in the last year has been that any packages that have to go through customs take considerably longer. It's not uncommon for packages I sent here from Texas via Airmail to take over a month to arrive. Really ridiculous considering packages I send to Europe (overseas!) generally arrive within about a week, and no more than two. Even packages to Australia arrive more quickly than packages to Canada. So I'd give it a bit longer and wouldn't worry too much yet. ..Al Quote Link to comment Share on other sites More sharing options...
Mayhem Posted November 2, 2005 Share Posted November 2, 2005 Still no sign of my copy... by now I figure it's either been lost, held up somewhere without any notice or it went surface and is REALLY taking its time getting here. Quote Link to comment Share on other sites More sharing options...
neotokeo2001 Posted November 3, 2005 Author Share Posted November 3, 2005 I still have 6 copies that have not been recieved. 2 I forgot to ship Nukey and Rick will ship tomorrow. The other 4 copies are all outside the USA. One way or another everyone will get their copy of the game. I'll try to get more info at the Post Office. Quote Link to comment Share on other sites More sharing options...
Albert Posted November 3, 2005 Share Posted November 3, 2005 I still have 6 copies that have not been recieved. 2 I forgot to ship Nukey and Rick will ship tomorrow. The other 4 copies are all outside the USA. One way or another everyone will get their copy of the game. I'll try to get more info at the Post Office. 958975[/snapback] I doubt you'll be able to get any additional information from the USPS regarding any international packages you have shipped. For regular surface and airmail, there's no tracking and no way to confirm delivery. Hopefully this situation will improve in the future. I have received several packages from Germany that actually had USPS Delivery Confirmation barcodes on them (!!), but there's no way for ME to send a package to Germany with Delivery Confirmation. ..Al Quote Link to comment Share on other sites More sharing options...
Necron99 Posted November 9, 2005 Share Posted November 9, 2005 what about tracking it using the canada post site for the ones sent to canada? dunno if it helps but it's a possiblity. http://www.canadapost.ca/ Quote Link to comment Share on other sites More sharing options...
Rick Weis Posted November 10, 2005 Share Posted November 10, 2005 I still have 6 copies that have not been recieved. 2 I forgot to ship Nukey and Rick will ship tomorrow. The other 4 copies are all outside the USA. One way or another everyone will get their copy of the game. I'll try to get more info at the Post Office. 958975[/snapback] i hope you did not ship this by priority mail because i have not received it yet.. i did get the dawn of the dead cart. Thank you!!! Rick Quote Link to comment Share on other sites More sharing options...
Atari Charles Posted November 10, 2005 Share Posted November 10, 2005 No sign of it in Canada yet. Quote Link to comment Share on other sites More sharing options...
128bytes Posted November 10, 2005 Share Posted November 10, 2005 I haven't recieved TronMan yet. I am thinking that packages from the States could be held up in Canada Customs. I've been out of town for a few weeks but have had a friend dilegently check my mail. I look forward to recieving it as it will be cool game to play on my Atari. Charles 958733[/snapback] Maybe Canada Post saw the way you picked on them during the "what happened to Trotter" mock-controversy and they are submitting their sweet revenge ...or maybe this is yet another mock-controversy. Quote Link to comment Share on other sites More sharing options...
Atari Charles Posted November 21, 2005 Share Posted November 21, 2005 No sign of the Tron Man cart yet. Quote Link to comment Share on other sites More sharing options...
Necron99 Posted November 21, 2005 Share Posted November 21, 2005 me either Hopefully I'll get it before X-mas as it was intended as a X-mas gift...*sigh* Quote Link to comment Share on other sites More sharing options...
Necron99 Posted December 2, 2005 Share Posted December 2, 2005 Update: Still nothing here Quote Link to comment Share on other sites More sharing options...
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