#robotics Logs

Jun 26 2018

12:01 AM rue_: I think the driver is faulted tho
12:05 AM rue_: the + side leaks - supply current
01:02 AM rue_: oh look I CAN tuck the R-2R under a 74HC595 DIP
01:02 AM rue_: and I can make the whole thing a SIP too
01:16 AM rue_: ok, so, I have an 8bit analog DAC for ~14c then, yay!
09:27 AM rue_: the MCP4725 is 12 bit, rail-rail, i2c, and $1 ea
09:29 AM rue_: so, I'm about 1/7 the price
09:29 AM z64555: ignoring the cost of development :P
09:29 AM rue_: the time to assemble
09:30 AM rue_: mine is just a 74HC595 and 15 resistors
09:30 AM veverak: https://scontent-ams3-1.xx.fbcdn.net/v/t1.15752-9/36274425_2009009219110453_3435108237681098752_n.jpg?_nc_cat=0&oh=e7e1afbdfb80335d3ddb2a72149c109a&oe=5BE23CAF
09:30 AM veverak: https://scontent-ams3-1.xx.fbcdn.net/v/t1.15752-9/36259243_2009009232443785_8566922384861298688_n.jpg?_nc_cat=0&oh=d3546160054a1feea370e50e50a79c00&oe=5BB90F32
09:30 AM veverak: I like the "click" mechanism
09:30 AM veverak: it works
09:30 AM veverak: and it required only one prototype to work correctly
09:31 AM rue_: what in it?
09:31 AM veverak: stm32 + apds9960 + 2xapa102
09:31 AM rue_: apds9960 + 2xapa102 ?
09:31 AM veverak: rgb sensor + 2x rgb leds
09:32 AM rue_: aaah
09:32 AM veverak: apds is also proximity/gesture sensor
09:32 AM veverak: :)
09:33 AM rue_: "flail for music"?
09:34 AM rue_: what do they mean gesture
09:35 AM veverak: nope, local company wanted sensors: rgb led pattern detection sensor, 'printer ejected paper' senso
09:35 AM veverak: r
09:35 AM veverak: so, we did that in one thing
09:35 AM veverak: rue_: it should be able to detect your hand waving up/down/left/right over it
09:35 AM veverak: tried that, not very reliable
09:36 AM rue_: hmm with 4 senors...
09:36 AM veverak: lookup doc for apds9960
09:37 AM veverak: truth to be told I kind of like that thing
09:37 AM rue_: reading
09:37 AM veverak: only part problematic is the fact that it has one i2c addr
09:37 AM veverak: that can't be modified
09:37 AM rue_: yea, we need i2c address modifier bus fitlers
09:38 AM veverak: well
09:38 AM veverak: we solved that with the fact that each "sensor" has stm32
09:38 AM rue_: master -> i2cdevice -> modifier -> i2c device-> modifier
09:38 AM veverak: so
09:38 AM veverak: master - i2c -> 'sensor stm32' - i2c -> apds
09:39 AM rue_: who comes up with this stuff?
09:39 AM veverak: so, we still can't have multiple apds9960 on single bus... thing is stm32 is on the bus and apds9960 is behind it on 'local bus', so it does not matter
09:39 AM veverak: rue_: what exactly?
09:40 AM rue_: chips like this
09:40 AM veverak: dunno
09:42 AM rue_: ok so their 'gesture' system just gives you 4 directions, in a fifo
09:42 AM veverak: yup
09:42 AM veverak: did not seem very reliable
09:43 AM rue_: not sure how you would properly noise fitler it, in theory a state machine, but...
09:44 AM veverak: use 8 sensors at once
09:44 AM veverak: their average has to be right ;)
09:44 AM rue_: not that, if your input is from a human
09:47 AM rue_: I had to have quite an error % margin on my knock sensor to have it work half descently
09:47 AM rue_: just try to knock the right sequence when listening to music
04:00 PM Tom_itx is now known as Tom_L
07:51 PM rue_shop3: ok, gonna make a dac
07:54 PM z64555: another one? sheesh. that's like the 5th this year alone
08:01 PM rue_shop3: this one with integrated serial
10:08 PM rue_shop3: sweeet, my dac module works great