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[23:30:04] <katsmeow> my LR44/AG13/357A came in, i have calipers again
[23:30:27] <rue_shop4> hi
[23:30:44] <rue_shop4> I think I worked out the problem iwth my tlc5940 code
[23:30:51] <rue_shop4> the chip is actually kinda stupid
[23:31:33] <katsmeow> what is the tlc5940 ?
[23:31:46] <rue_shop4> oh, no I'm wrong...
[23:31:56] <rue_shop4> its a 12 bit, 16 channel pwm system
[23:35:43] <rue_shop4> it SEEMS like a great chip, its not being tho
[23:36:59] <katsmeow> what's it;s problem?
[23:37:16] <rue_shop4> mainly cause the pwm clocking and the writing of the control value have to be carefully co-ordinated
[23:37:30] <rue_shop4> they aren't asynchonous
[23:38:17] <katsmeow> that's wierd
[23:45:40] <rue_shop4> it should have been turned off if the pwm value was greater
[23:49:34] <katsmeow> how do you know when to write a particular channel's value?
[23:51:03] <katsmeow> parse error : Quiescent current: 10mA (12V liter 20V, the output voltage, the higher the current will increase too quiet)
[23:51:05] <rue_shop4> I suppose your supposed to do it during the BLANK pulse, but
[23:51:15] <rue_shop4> during that pulse, the outputs are off
[23:51:33] <katsmeow> umm, isn't it bad to have all the outputs go dead?
[23:51:54] <rue_shop4> it kinda makes 100% duty a problem
[23:52:26] <rue_shop4> tho, at 300Hz for the pwm, I can probably write all the values before the first tick comes up for pwm count
[23:52:54] <rue_shop4> hmm 1.2Mhz
[23:53:00] <rue_shop4> maybe not
[23:53:19] <rue_shop4> I can extend the blank pulse time, this chip is annoying as hell
[23:53:31] <rue_shop4> its almost like generating the pwm yourself
[23:53:37] <katsmeow> sounds like it
[23:53:59] <rue_shop4> I'll try this interrupt driven thing
[23:54:04] <katsmeow> why aren't you usng avr that have pwm pins?
[23:54:10] <rue_shop4> I need 16 channels
[23:54:26] <katsmeow> aren't tehre avr with 8 pwm pins?
[23:54:44] <rue_shop4> tho, 6 bit would probably be fine, and I could do 6 bit pwm in softare at 300Hz
[23:54:57] <rue_shop4> not one of the avrs I have for this project
[23:55:12] <rue_shop4> I bought lots of these 5940s I'd like to find a way to use them up
[23:56:45] <katsmeow> what about a 18bit register as a buffer, write to it whenever you want, the chip clocks it in when you set a trigger of some kind
[23:57:13] <rue_shop4> I'm trying not to use a million chips either
[23:57:24] <rue_shop4> already, the 1A motor drivers are huge
[23:57:55] <katsmeow> o
[23:59:57] <rue_shop4> so far I ahve a tiny26 for a slave ADC, an atmega8 for a loop controller, the 5940 for pwm generation, and 4060 to generate the clockS for it, and two uls2308 to help drive mosfets, along with the 32 TO-220 mosfets