Hi
Iam looking for advice.
I want to translate and buffer 7 signals from mpu to outside world. What should I use to do it? It is one way only from 3.3 to 5v.
Can I just use something like 74AHC244 8bit Buffer/Line Driver 3 state? If yes what should I do with unused one? Just leave it floating?
3.3v->5v 7 signals
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arkadiusz.makarenko
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3.3v->5v 7 signals
Do not trust people. They are capable of greatness.
~ Stanislaw Lem
~ Stanislaw Lem
Re: 3.3v->5v 7 signals
It depends exactly what your doing... as TTL inputs will accept 3.3V as a HI anyway...
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viewtopic.php?f=17&t=1585 Have you done the Mandatory Fixes ?
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https://www.exxosforum.co.uk/atari/store2/ - All my hardware mods for sale - Please help support by making a purchase.
viewtopic.php?f=17&t=1585 Have you done the Mandatory Fixes ?
Just because a lot of people agree on something, doesn't make it a fact. ~exxos ~
People should find solutions to problems, not find problems with solutions.
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arkadiusz.makarenko
- Moderator Team
- Posts: 1208
- Joined: Wed Jun 19, 2019 7:36 am
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Re: 3.3v->5v 7 signals
It is external signal which will be sent outside, maybe over the cables to external device. And I would like to protect mpu as well.
Do not trust people. They are capable of greatness.
~ Stanislaw Lem
~ Stanislaw Lem
Re: 3.3v->5v 7 signals
74AHCT244 or 74AHCT541 work well. You can also use 74HCT.
Just tie the unused input to ground or 3v3.
Just tie the unused input to ground or 3v3.
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arkadiusz.makarenko
- Moderator Team
- Posts: 1208
- Joined: Wed Jun 19, 2019 7:36 am
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Re: 3.3v->5v 7 signals
Thank you.
Lets see how it will work out.
Do not trust people. They are capable of greatness.
~ Stanislaw Lem
~ Stanislaw Lem
Re: 3.3v->5v 7 signals
Use a 74LVC244 with pull-up to 5V on the output (5V side).
It's a 3.3v device with 5V i/o support. I use it a lot of places exactly for this.
Rodolphe
It's a 3.3v device with 5V i/o support. I use it a lot of places exactly for this.
Rodolphe
Working ones : MegaSTE (68020) / TT030 / Falcon with AB040 & Eclipse / 1040STF
Need testing : Falcon with CT2
Need testing : Falcon with CT2
Re: 3.3v->5v 7 signals
I've been using 74AHCT245As for my VGA mod, since they only cost AUD 50c each and they do the job. If you only need a single-directional driver they work the same as the 244s (I just tie DIR to ground).