Timeline for Different results for different parallel ports, same circuit. why?
Current License: CC BY-SA 4.0
12 events
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| Dec 15, 2021 at 7:00 | history | bumped | CommunityBot | This question has answers that may be good or bad; the system has marked it active so that they can be reviewed. | |
| Aug 2, 2021 at 19:01 | history | bumped | CommunityBot | This question has answers that may be good or bad; the system has marked it active so that they can be reviewed. | |
| Mar 30, 2021 at 3:03 | history | bumped | CommunityBot | This question has answers that may be good or bad; the system has marked it active so that they can be reviewed. | |
| Nov 25, 2020 at 14:00 | history | bumped | CommunityBot | This question has answers that may be good or bad; the system has marked it active so that they can be reviewed. | |
| Jan 14, 2020 at 0:09 | answer | added | chocapic | timeline score: 1 | |
| Aug 3, 2018 at 14:47 | comment | added | Mike -- No longer here | I read some documentation online for it and it didn't help unless there is better documentation I'm unaware of. | |
| Aug 3, 2018 at 10:09 | comment | added | Jasen Слава Україні |
I juste looked closer at the schematic, have you tried the software avrp , there may be some useful hints in the documentation,
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| Aug 3, 2018 at 6:11 | comment | added | Mike -- No longer here | @Jasen I just tried out ioctls with the ppdev driver and the results are exactly the same. No better. Also, just for crude testing, I connected a 1K resistor between busy and ground on the problematic computer parallel port and reading the port then showed that the busy line does work but somehow it doesn't when my circuit is attached | |
| Aug 3, 2018 at 4:51 | comment | added | Mike -- No longer here | I made a circuit similar to this before but I used tristate logic gates but at least the programming worked when I powered it but when I attempted a hardware reset, the circuit didn't work and i had to remove power and apply power again to get the circuit to work. As for serial driver, USB is too over-the-top and trying to use UART is also ridiculous. At least with bit-banging I got somewhere but I will take note about the RC filters. What's the worst case timing for the RC filter? | |
| Aug 3, 2018 at 4:18 | comment | added | Jack Creasey | You only use D0,1 and D2-7 are floating. Many parallel port adapters have RC filters on the lines, so I would fully expect you'd read C0 for input values. Since you clearly need a serial driver for the programmer, why are you not testing with that? | |
| Aug 3, 2018 at 3:55 | comment | added | Jasen Слава Україні | don't go banging ports on linux, install the parport_pc driver and use the apropriate IOCTL calls. | |
| Aug 3, 2018 at 3:15 | history | asked | Mike -- No longer here | CC BY-SA 4.0 |