#garfield Logs

Nov 16 2024

12:28 AM Tom_L: hole mill works
12:43 AM rue_mohr: yay!
12:53 AM rue_shop2: yay, I fixed the 8051 pcb
12:53 AM rue_shop2: tore off a pad removing the 373 tho, grrrr
12:54 AM rue_shop2: good library, that didn't take long
12:56 AM rue_mohr: so polprog , the pcb is not wrong, but the chip part number for the output is
12:56 AM rue_mohr: 74xx374, not 74xx373
01:01 AM rue_mohr: http://ruemohr.org/~ircjunk/tempimage/p1330227.jpg
01:02 AM rue_mohr: the bodge wire is a pad I broke changing the chip from 74373 to 74374
02:18 PM OK2AWO: hey guys
02:36 PM rue_mohr: hey
02:36 PM rue_mohr: who are you?
03:00 PM OK2AWO: used to be OK9UWU (Felix on twitter)
03:01 PM rue_mohr: hi!
03:01 PM rue_mohr: http://ruemohr.org/~ircjunk/tempimage/p1330227.jpg
03:02 PM rue_mohr: special content :]
03:02 PM rue_mohr: http://ruemohr.org/~ircjunk/tempimage/p1330226.jpg
03:07 PM rue_mohr: polprog, when are you going to surface again?
03:08 PM OK2AWO: i am just talking with him over on Discord lol
03:08 PM rue_mohr: POLPROG
03:48 PM OK2AWO: i am just messing around with Fractional PLLs and using them as a fancy DACs for FM
03:49 PM OK2AWO: its great to have a box where on one side you input some SPI noise and on the other you get a broadcast quality FM signal... in this case on 3.024GHz hah!
03:51 PM OK2AWO: just need to figure out how to get SPI working on Raspberry pi or other SBCs so i can directly transmit some digital data, instead of sampling it with the 328p ADC at mere 10bits
03:53 PM Tom_L: rue_mohr, http://tom-itx.no-ip.biz:443/~webpage/cnc/JT-SHOP/flexgui/hole_mill_pattern.mkv
04:51 PM rue_mohr: OK2AWO, hmmm
04:52 PM OK2AWO: i am slowly starting to loose my mind over this, getting extremelly bad ideas such as sending data to the arduino with SMBus/I2C and using it as an adapter to SPI... duh
04:53 PM OK2AWO: unbelievable how much they advertise RPi as a great learning machine for robotics and what not BUT THERE'S NOTHING FOR THE GPIO SPI........ yeah i could use ioctl() but i dont know if i want to do that
04:54 PM rue_mohr: you can bit bang that stuff you know, its not time critical
04:55 PM OK2AWO: i could theoretically, as long as i can doit at some 190kHz/s
04:55 PM OK2AWO: so SPI clock at 2.2MHz
04:56 PM OK2AWO: (12bits modulation word * audio sampling rate)
05:00 PM OK2AWO: altho, you are right, i would have to bitbang it either way, due to the way how the PLL registers are loaded
05:17 PM rue_shop2: ok, assembled 4 more of the 8051 baords and they all seen to be doing ok (after touching up some soldering)
05:17 PM rue_shop2: OK2AWO, nor SPI or I2C have a required clock rate
05:18 PM rue_shop2: you could clock them from a 555 if you wanted to
05:21 PM OK2AWO: damnit
05:21 PM OK2AWO: so RPi Pico, LPT or FPGA...
05:27 PM OK2AWO: it could be rather interesting project for the FPGA... using UART at 2.304Mbit/s
05:30 PM rue_shop2: your not streaming to a DAC
05:31 PM rue_shop2: 1kbit is fine
05:31 PM OK2AWO: i sort of am
05:31 PM OK2AWO: i am using the PLL as a DAC
05:31 PM rue_shop2: ... what?
05:31 PM rue_shop2: ok..
05:31 PM OK2AWO: https://www.skyworksinc.com/-/media/SkyWorks/Documents/Products/1-100/101349C.pdf
05:35 PM OK2AWO: currently i am sending in just 10bit modulation word, that means 10clock cycles on the SPI clock per audio sample, 1 cycle on the LE, if i would want to send full 12bits, that'd be 12clock cycles per audio sample, lets say i want to transmit with MPX (so stereo @ 38kHz + RDS at 57kHz + some overhead) * 2 i am at some 150kS/s of audio sampling rate, to make my life easier i can just use the 192kS/s that's a industry standart
06:47 PM rue_mohr: but
06:50 PM Tom_L: http://tom-itx.no-ip.biz:443/~webpage/cnc/JT-SHOP/flexgui/hole_drill_counterbore.mkv
06:51 PM rue_mohr: uh
06:51 PM rue_mohr: it got mixed up, thats the hole pattern gain
06:52 PM Tom_L: hole with counterbore
06:53 PM rue_mohr: that video is the hole pattern tho
06:53 PM rue_mohr: oh then after
06:53 PM Tom_L: right but the counterbore added is new
06:53 PM Tom_L: optional
06:54 PM rue_mohr: got rain with slush here
07:37 PM rue_shop2: polprog, the 8051 board, I set the serial LEDs up for H = On, but as serial idles high, it might be better to reverse them and use L = on
09:55 PM rue_shop2: dual 90
09:56 PM rue_shop2: 28w sockets
09:56 PM rue_shop2: common cathode rgb
09:57 PM Tom_L: whasssup?
09:58 PM Tom_L: ever done much tube hacking?
09:59 PM Tom_L: i never understood that tech much
10:45 PM rue_mohr: radio tube?
11:12 PM rue_mohr: polprog, this program is awesome
11:12 PM rue_mohr: tell me when your up and I'll shoot you back a copy that I modified
11:13 PM rue_mohr: got some use out of it today