Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]
Groups > sci.electronics.design > #518813
| From | Gerhard Hoffmann <ghf@hoffmann-hochfrequenz.de> |
|---|---|
| Newsgroups | sci.electronics.design |
| Subject | Re: Need to construct the logical reverse of a 7448 - perhaps using a GAL |
| Date | 2018-10-09 14:23 +0200 |
| Message-ID | <g23kuhFsmo5U1@mid.individual.net> (permalink) |
| References | <FpWdnYuq0ujJaSbGnZ2dnUU7-I_NnZ2d@giganews.com> <pph9tk$9rl$1@dont-email.me> <UvSdnbpnaveTxSHGnZ2dnUU7-cfNnZ2d@giganews.com> |
Am 09.10.2018 um 09:26 schrieb John Robertson: > On 2018/10/08 9:15 PM, tom wrote: >> One way to do it is to use an EPROM. Connect the seven segments to >> AD0 to >> AD6. Use the first four data outputs (D0 to D3) for the BCD code. Make >> up a >> table with the correct memory locations to put 1s in for the decoder. Tie >> /CE and /CS to the appropriate levels. A 2716 would work fine, just >> ignore >> the unwanted outputs and tie AD7 to ground. >> >> >> Regards >> >> > > Was looking for tiny, I have lots of Eproms, but space, eh? An Eprom > would be simple too. The look up table would only take 15 bytes, you > would use the Address lines A0-A3 with the Data lines being the outputs. > Easy, but too big for my application. I guess I could use a tiny EPROM, > should have looked for that I guess. Got caught up in elegant solutions... Someone I knew got bitten by that. He had an EPROM that contained dynamic logic. It would present the correct data, but after some time the data turned wrong. Hold time was not eternal. Perfectly OK for a processor, but not for character mapping of a mechanical teletype. :-) Gerhard
Back to sci.electronics.design | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread
Need to construct the logical reverse of a 7448 - perhaps using a GAL John Robertson <spam@flippers.com> - 2018-10-08 17:20 -0700
Re: Need to construct the logical reverse of a 7448 - perhaps using a GAL Jeff Liebermann <jeffl@cruzio.com> - 2018-10-08 18:57 -0700
Re: Need to construct the logical reverse of a 7448 - perhaps using a GAL John Robertson <spam@flippers.com> - 2018-10-08 19:08 -0700
Re: Need to construct the logical reverse of a 7448 - perhaps using a GAL John Robertson <spam@flippers.com> - 2018-10-08 19:13 -0700
Re: Need to construct the logical reverse of a 7448 - perhaps using a GAL John Robertson <spam@flippers.com> - 2018-10-08 19:27 -0700
Re: Need to construct the logical reverse of a 7448 - perhaps using a GAL Jeff Liebermann <jeffl@cruzio.com> - 2018-10-08 21:06 -0700
Re: Need to construct the logical reverse of a 7448 - perhaps using a GAL Jeff Liebermann <jeffl@cruzio.com> - 2018-10-08 21:36 -0700
Re: Need to construct the logical reverse of a 7448 - perhaps using a GAL gnuarm.deletethisbit@gmail.com - 2018-10-08 20:27 -0700
Re: Need to construct the logical reverse of a 7448 - perhaps using a GAL John Robertson <spam@flippers.com> - 2018-10-08 21:19 -0700
Re: Need to construct the logical reverse of a 7448 - perhaps using a GAL Jeff Liebermann <jeffl@cruzio.com> - 2018-10-08 21:40 -0700
Re: Need to construct the logical reverse of a 7448 - perhaps using a GAL John Robertson <spam@flippers.com> - 2018-10-09 00:20 -0700
Re: Need to construct the logical reverse of a 7448 - perhaps using a GAL gnuarm.deletethisbit@gmail.com - 2018-10-10 15:43 -0700
Re: Need to construct the logical reverse of a 7448 - perhaps using a GAL John Robertson <spam@flippers.com> - 2018-10-10 18:46 -0700
Re: Need to construct the logical reverse of a 7448 - perhaps using a GAL gnuarm.deletethisbit@gmail.com - 2018-10-08 22:11 -0700
Re: Need to construct the logical reverse of a 7448 - perhaps using a GAL John Robertson <spam@flippers.com> - 2018-10-09 00:27 -0700
Re: Need to construct the logical reverse of a 7448 - perhaps using a GAL Rob <nomail@example.com> - 2018-10-09 17:08 +0000
Re: Need to construct the logical reverse of a 7448 - perhaps using a GAL "tom" <tmiller11147@verizon.net> - 2018-10-09 00:15 -0400
Re: Need to construct the logical reverse of a 7448 - perhaps using a GAL John Robertson <spam@flippers.com> - 2018-10-09 00:26 -0700
Re: Need to construct the logical reverse of a 7448 - perhaps using a GAL Gerhard Hoffmann <ghf@hoffmann-hochfrequenz.de> - 2018-10-09 14:23 +0200
Re: Need to construct the logical reverse of a 7448 - perhaps using a GAL jrwalliker@gmail.com - 2018-10-09 06:43 -0700
Re: Need to construct the logical reverse of a 7448 - perhaps using a GAL John Robertson <spam@flippers.com> - 2018-10-09 08:41 -0700
Re: Need to construct the logical reverse of a 7448 - perhaps using a GAL dplatt@coop.radagast.org (Dave Platt) - 2018-10-09 10:50 -0700
Re: Need to construct the logical reverse of a 7448 - perhaps using a GAL Jeff Liebermann <jeffl@cruzio.com> - 2018-10-09 09:15 -0700
Re: Need to construct the logical reverse of a 7448 - perhaps using a GAL John Robertson <spam@flippers.com> - 2018-10-09 10:01 -0700
Re: Need to construct the logical reverse of a 7448 - perhaps using a GAL Tauno Voipio <tauno.voipio@notused.fi.invalid> - 2018-10-09 21:01 +0300
Re: Need to construct the logical reverse of a 7448 - perhaps using a GAL John Robertson <spam@flippers.com> - 2018-10-09 11:13 -0700
Re: Need to construct the logical reverse of a 7448 - perhaps using a GAL bitrex <user@example.net> - 2018-10-09 18:35 -0400
Re: Need to construct the logical reverse of a 7448 - perhaps using a GAL TTman <kraken.sankey@gmail.com> - 2018-10-09 23:43 +0100
Re: Need to construct the logical reverse of a 7448 - perhaps using a GAL bitrex <user@example.net> - 2018-10-09 19:49 -0400
Re: Need to construct the logical reverse of a 7448 - perhaps using a GAL bitrex <user@example.net> - 2018-10-09 19:50 -0400
Re: Need to construct the logical reverse of a 7448 - perhaps using a GAL Jeff Liebermann <jeffl@cruzio.com> - 2018-10-09 17:25 -0700
Re: Need to construct the logical reverse of a 7448 - perhaps using a GAL John Robertson <spam@flippers.com> - 2018-10-09 19:15 -0700
Re: Need to construct the logical reverse of a 7448 - perhaps using a GAL gnuarm.deletethisbit@gmail.com - 2018-10-10 16:46 -0700
Re: Need to construct the logical reverse of a 7448 - perhaps using a GAL Gerhard Hoffmann <ghf@hoffmann-hochfrequenz.de> - 2018-10-11 02:08 +0200
Re: Need to construct the logical reverse of a 7448 - perhaps using a GAL gnuarm.deletethisbit@gmail.com - 2018-10-10 18:37 -0700
Re: Need to construct the logical reverse of a 7448 - perhaps using a GAL Gerhard Hoffmann <ghf@hoffmann-hochfrequenz.de> - 2018-10-11 13:35 +0200
Re: Need to construct the logical reverse of a 7448 - perhaps using a GAL gnuarm.deletethisbit@gmail.com - 2018-10-10 15:45 -0700
Re: Need to construct the logical reverse of a 7448 - perhaps using a GAL John Robertson <spam@flippers.com> - 2018-10-10 18:50 -0700
Re: Need to construct the logical reverse of a 7448 - perhaps using a GAL Jasen Betts <jasen@xnet.co.nz> - 2018-10-11 05:39 +0000
Re: Need to construct the logical reverse of a 7448 - perhaps using a GAL bitrex <user@example.net> - 2018-10-09 02:18 -0400
Re: Need to construct the logical reverse of a 7448 - perhaps using a GAL TTman <kraken.sankey@gmail.com> - 2018-10-09 17:51 +0100
Re: Need to construct the logical reverse of a 7448 - perhaps using a GAL bitrex <user@example.net> - 2018-10-09 17:38 -0400
Re: Need to construct the logical reverse of a 7448 - perhaps using a GAL John Larkin <jjlarkin@highland_snip_technology.com> - 2018-10-09 17:52 -0700
Re: Need to construct the logical reverse of a 7448 - perhaps using a GAL John Robertson <spam@flippers.com> - 2018-10-09 19:16 -0700
Re: Need to construct the logical reverse of a 7448 - perhaps using a GAL bitrex <user@example.net> - 2018-10-09 22:48 -0400
csiph-web