Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]
Groups > comp.lang.forth > #12805
"Paul Rubin" <no.email@nospam.invalid> wrote in message news:7xd3591xin.fsf@ruckus.brouhaha.com... > Andrew Haley <andrew29@littlepinkcloud.invalid> writes: > > All physical channels are analog. What else are you looking for? > > How to convert sequences of a/d samples into bits, and vice versa, > taking the actual characteristics of the analog channel (in this case > that it is presumably ac coupled) into account. The "Line code" article > seems to be about the case where each sample is either a 1 or a 0, > rather than an 8-bit number approximating a continuous quantity. > Analog-to-Digital converter (ADC) http://en.wikipedia.org/wiki/Analog-to-digital_converter Digital-to-Analog converter (DAC) http://en.wikipedia.org/wiki/Digital-to-analog_converter If you haven't been around for a while, you're probably unaware of this: http://en.wikipedia.org/wiki/Flash_ADC There are also Flash DACs. IIRC, the original Amiga's used one with high precision resistors for their video output (12-bits as 3 channels of 4-bits). You'll also find old articles in magazines like Radio Electronics that use them. Back then, ADCs and DACs were expensive, rare, and weren't very fast. R-2R ladder http://en.wikipedia.org/wiki/Resistor_ladder discrete R-2R DACs http://www.sonicillusions.co.uk/discrete_dac.htm http://www.youtube.com/watch?v=b-vUg7h0lpE Originally, a Flash DAC/ADC was a discrete analog circuit, a non-integrated circuit, which handled DAC/ADC conversion. They were based on series resistor arrays. They're called "flash" because they could handle high speed conversion before ICs of the era were capable of those higher speeds (1980's), and were and still are cheap. They're not as precise as IC based circuits. They depend on the precision of the resistors. Today, ICs can handle very high speeds, so Flash circuits aren't really needed, but they can be a cheap solution for hobby projects. The Amiga's managed to get video speeds (early computer video). So, today, low-end video and audio should be doable with one, maybe upto 4 to 6Mhz (guess). IIRC, NTSC had a 4.5Mhz bandwidth. Such a flash DAC might be able to go higher or be somewhat lower, but that's alot of bandwidth, unless you're doing something extreme, i.e., modern. Rod Pemberton
Back to comp.lang.forth | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread
post your solution to this problem quiet_lad <gavcomedy@gmail.com> - 2012-06-03 14:33 -0700
Re: post your solution to this problem "Rod Pemberton" <do_not_have@notemailntt.cmm> - 2012-06-03 20:59 -0400
Re: post your solution to this problem quiet_lad <gavcomedy@gmail.com> - 2012-06-03 19:06 -0700
Re: post your solution to this problem "Elizabeth D. Rather" <erather@forth.com> - 2012-06-03 18:27 -1000
Re: post your solution to this problem quiet_lad <gavcomedy@gmail.com> - 2012-06-03 19:49 -0700
Re: post your solution to this problem "Elizabeth D. Rather" <erather@forth.com> - 2012-06-03 18:28 -1000
DSP question (software modem) Paul Rubin <no.email@nospam.invalid> - 2012-06-03 22:22 -0700
Re: DSP question (software modem) Mark Wills <markrobertwills@yahoo.co.uk> - 2012-06-04 02:19 -0700
Re: DSP question (software modem) Paul Rubin <no.email@nospam.invalid> - 2012-06-04 03:07 -0700
Re: DSP question (software modem) Andrew Haley <andrew29@littlepinkcloud.invalid> - 2012-06-04 04:32 -0500
Re: DSP question (software modem) Paul Rubin <no.email@nospam.invalid> - 2012-06-04 03:15 -0700
Re: DSP question (software modem) Andrew Haley <andrew29@littlepinkcloud.invalid> - 2012-06-04 05:46 -0500
Re: DSP question (software modem) Paul Rubin <no.email@nospam.invalid> - 2012-06-04 12:16 -0700
Re: DSP question (software modem) Andrew Haley <andrew29@littlepinkcloud.invalid> - 2012-06-04 14:55 -0500
Re: DSP question (software modem) Paul Rubin <no.email@nospam.invalid> - 2012-06-04 13:32 -0700
Re: DSP question (software modem) Andrew Haley <andrew29@littlepinkcloud.invalid> - 2012-06-07 05:20 -0500
Re: DSP question (software modem) Paul Rubin <no.email@nospam.invalid> - 2012-06-07 10:01 -0700
Re: DSP question (software modem) quiet_lad <gavcomedy@gmail.com> - 2012-06-07 11:04 -0700
Re: DSP question (software modem) Andrew Haley <andrew29@littlepinkcloud.invalid> - 2012-06-07 17:21 -0500
Re: DSP question (software modem) Paul Rubin <no.email@nospam.invalid> - 2012-06-07 20:36 -0700
Re: DSP question (software modem) "Rod Pemberton" <do_not_have@notemailntt.cmm> - 2012-06-08 02:36 -0400
Re: post your solution, and don't over write my thread, or I'll do something to Paul Rubbin quiet_lad <gavcomedy@gmail.com> - 2012-06-07 23:55 -0700
Re: post your solution, and don't over write my thread ... BruceMcF <agila61@netscape.net> - 2012-06-08 09:56 -0700
Re: DSP question (software modem) Andrew Haley <andrew29@littlepinkcloud.invalid> - 2012-06-08 07:52 -0500
Re: DSP question (software modem) Paul Rubin <no.email@nospam.invalid> - 2012-06-08 11:14 -0700
Re: DSP question (software modem) "Rod Pemberton" <do_not_have@notemailntt.cmm> - 2012-06-08 16:29 -0400
Re: DSP question (software modem) Paul Rubin <no.email@nospam.invalid> - 2012-06-08 19:59 -0700
Re: DSP question (software modem) Richard Owlett <rowlett@pcnetinc.com> - 2012-06-08 22:37 -0500
Re: DSP question (software modem) Andrew Haley <andrew29@littlepinkcloud.invalid> - 2012-06-09 04:36 -0500
Re: DSP question (software modem) Paul Rubin <no.email@nospam.invalid> - 2012-06-09 09:41 -0700
Re: post your solution and Paul rubin is a stinker for changing it, you bugger paul!! quiet_lad <gavcomedy@gmail.com> - 2012-06-06 15:52 -0700
Re: post your solution and Paul rubin is a stinker for changing it, you bugger paul!! BruceMcF <agila61@netscape.net> - 2012-06-06 16:09 -0700
Re: post your solution, please no one change subject, start new thread of your own instead quiet_lad <gavcomedy@gmail.com> - 2012-06-07 11:02 -0700
Re: post your solution, please no one change subject, start new thread of your own instead "Elizabeth D. Rather" <erather@forth.com> - 2012-06-07 08:28 -1000
Re: post your solution, please no one change subject, start new thread of your own instead quiet_lad <gavcomedy@gmail.com> - 2012-06-07 23:58 -0700
Re: post your solution, please no one change subject, start new thread of your own instead Paul Rubin <no.email@nospam.invalid> - 2012-06-07 11:53 -0700
Re: post your solution, please no one change subject, start new thread of your own instead quiet_lad <gavcomedy@gmail.com> - 2012-06-07 23:54 -0700
Re: post your solution, please no one change subject, start new thread of your own instead quiet_lad <gavcomedy@gmail.com> - 2012-06-08 00:00 -0700
Re: post your solution, please no one change subject, start new thread of your own instead BruceMcF <agila61@netscape.net> - 2012-06-08 10:08 -0700
[OT] About cancellation of quiet_lad's messages, was Re: post your .... of your own instead Albert van der Horst <albert@spenarnc.xs4all.nl> - 2012-06-08 11:34 +0000
Re: post your solution, please no one change subject, start new thread of your own instead BruceMcF <agila61@netscape.net> - 2012-06-08 10:03 -0700
Re: post your solution and Paul rubin is a stinker for changing it, you bugger paul!! "Rod Pemberton" <do_not_have@notemailntt.cmm> - 2012-06-06 19:28 -0400
This thread is a load of s**t Mark Wills <markrobertwills@yahoo.co.uk> - 2012-06-07 00:54 -0700
Re: post your solution and Paul rubin is a stinker for changing it, you bugger paul!! quiet_lad <gavcomedy@gmail.com> - 2012-06-07 11:03 -0700
Re: post your solution quiet_lad <gavcomedy@gmail.com> - 2012-06-07 11:10 -0700
Re: DSP question (software modem) Richard Owlett <rowlett@pcnetinc.com> - 2012-06-04 07:08 -0500
Re: post your solution to this problem John Passaniti <john.passaniti@gmail.com> - 2012-06-04 09:06 -0700
Re: post your solution to this problem quiet_lad <gavcomedy@gmail.com> - 2012-06-06 15:51 -0700
Re: post your solution to this problem "WJ" <w_a_x_man@yahoo.com> - 2012-06-08 16:12 +0000
Re: post your solution to this problem "WJ" <w_a_x_man@yahoo.com> - 2012-06-09 16:15 +0000
Re: post your solution to this problem BruceMcF <agila61@netscape.net> - 2012-06-08 10:15 -0700
csiph-web