Read: 209 times
Msg Score: +2
+2 Good Answer/Helpful
|#184674 - What situation would that be?|
Responding to: Richard Erlacher's previous message
But note that the original EPROM chips did not support electrical erase. And applying UV light meant bulk erase.
So the use of a single external EPROM would not allow the lower part of that EPROM to contain a loader handling any serial port and then have that loader receive more program to burn into upper parts of the EPROM - especially since the EPROM would not run the processor while being programmed.
Even most flash chips have the limitation that they can't serve out code while having other flash sectors being erased/reprogrammed.
So the simplest solution would be to have two memory chips. One EPROM or flash chip with a boot loader. But how (?) would that program get a boot loader when there are no stand-alone programmer available to program it?
The second memory could be a RAM or a flash, and could get the contents by the boot loader program.
But no - there would not be anything simple about the above. So we would be back to my original post.
Yes - a programmer can be written. Yes, the processor can be used. But it would cost. It would take time. And it would probably not work because it would require too many individual steps to be correct. And someone who starts from scratch would not have the equipment and experience to figure out all the broken steps until the design finally started to work.
A fraction of that time and a fraction of the cost, could be used to buy a development board with a modern processor with a RS-232 or USB interface where a PC program could send a new program. And with a modern processor that would have internal, hardware, support for debugging of the downloaded program.
Going the new route, would mean lots of time available to learn new skills on a working platform.
Going the old route would give lots of experiences that may not be wanted at this time. Like 100 different things that can go wrong ending a project in failure.
That's what I'd use in this sort of situation.
And what situation would that be? You starting from scratch, without any existing software? No existing hardware but a dumb processor and one or more UV-erasable EPROM chips but without any UV eraser? No tools to fill that EPROM with contents? No tools to drive raw processor pins to use as a building block for a programmer? No tool capable of receiving RS-232 data from a PC to send into latches to then (together with pulsing of address counters) program the EPROM?
Anyone who gets to this forum with the question the OP had, would be in a position where it doesn't matter what "can" be done. The important thing is that with lacking tools and lacking experience, lots of things that can be done just shouldn't be attempted. Becaus the cost would be too high. Because the failure probability would be too high. Just because other - very cheap - alternatives would allow much more learning in way shorter time.
If you have a $300 old car, it isn't meaningful to invest $3000 to try to get it to run a bit better.
If you have the skills and a truly unique wreck, it might be meaningful to invest $30,000 instead. Just because you will be able to create a museum-class vehicle in mint condition.
This is not a thread where an experienced developer is trying to recreate an important historical artifact, but someone who have a "wreck" on his hands and isn't realizing that the cost it would take to make it usable is higher than the cost of buying a new SDK complete with documentation.
|How to write programs to internal memory with RS232???||Jacob Drake||11/11/11 00:56|
|What processor||Per Westermark||11/11/11 01:05|
|And the winner is...||Jacob Drake||11/11/11 11:13|
|fuggetabutit||Erik Malund||11/11/11 11:42|
|Hmmmmmm||Jacob Drake||11/11/11 11:53|
|sure there is||Erik Malund||11/11/11 12:15|
|Costly failure||Per Westermark||11/11/11 12:20|
|Well, the UV thing confuses me...||Jacob Drake||11/11/11 12:26|
|well, then ....||Erik Malund||11/11/11 12:56|
|OTP or mask-programmed||Per Westermark||11/11/11 13:00|
|Isn't that a clue?||Richard Erlacher||11/11/11 14:09|
|Wrong! It won't work with THIS part!||Richard Erlacher||11/11/11 14:08|
|8032||Per Westermark||11/11/11 14:39|
|Actually ...||Richard Erlacher||11/11/11 23:50|
|What situation would that be?||Per Westermark||11/12/11 05:25|
|I think you're confusing two different parts.||Richard Erlacher||11/13/11 01:09|
|There's the thing!||Andy Neil||11/12/11 05:37|
|It all depends on what you mean by experienced.||Jacob Drake||11/12/11 12:54|
|RE: It all depends on what you mean by, "experienced"||Andy Neil||11/12/11 13:03|
|"Level" is such a relative term||Jacob Drake||11/12/11 17:35|
|That's the reason||Richard Erlacher||11/13/11 01:15|
|8032?||Jacob Drake||11/12/11 00:47|
|Yes - but is it worth it?||Andy Neil||11/12/11 04:30|
|It's a long, circuitous path ...||Richard Erlacher||11/13/11 01:24|
|I have an external UV EPROM||Jacob Drake||11/12/11 00:38|
|If you don't know that, ...||Andy Neil||11/12/11 04:35|
|Unless you have specific interest in vintage electronics ...||Andy Neil||11/11/11 13:13|
|So...I've made a decision..sorta||Jacob Drake||11/12/11 23:51|
|One step at a time||Andy Neil||11/13/11 00:21|
|Any specific one though?||Jacob Drake||11/13/11 00:28|
|This one?||Andy Neil||11/13/11 01:04|
|Not this one!||Richard Erlacher||11/11/11 13:55|
|Hmmm, a goal?||Jacob Drake||11/12/11 00:44|
|Wrong road!||Andy Neil||11/12/11 05:07|
|Regarding knowledge of electronics.||Jacob Drake||11/12/11 12:57|
|RE: "fourth grade"||Andy Neil||11/12/11 13:10|
|RE:RE:Fourth grade||Jacob Drake||11/12/11 17:36|
|if the "self taught home-school class" refer to the archaric||Erik Malund||11/12/11 08:17|
|When throwing out bathwater, take care to retain baby...||Andy Neil||11/12/11 10:16|
|out of sheer nostalgia||Erik Malund||11/12/11 16:44|
|It might, in fact, be a good thing to go back farther||Richard Erlacher||11/13/11 01:37|
|Interesting||Jacob Drake||11/14/11 00:15|
|You need to know much more about two things ...||Richard Erlacher||11/14/11 12:51|
|About other processors||Jacob Drake||11/12/11 13:01|
|The prices were on the page!||Andy Neil||11/12/11 13:07|
|SiLabs Boards||Michael Karas||11/12/11 13:42|
|Integrated||Per Westermark||11/12/11 14:57|
|here||Erik Malund||11/12/11 16:34|
|Code flash not always able to replace EEPROM||Per Westermark||11/12/11 16:56|
|agreed||Erik Malund||11/12/11 17:24|
|Yes||Jacob Drake||11/12/11 17:42|
|Yes||Jacob Drake||11/12/11 17:42|
|Maybe a heretic idea...||Matthias Arndt||11/13/11 04:44|
|There's a problem with these ...||Richard Erlacher||11/13/11 12:56|
|Not for the intended purpose....||Matthias Arndt||11/14/11 00:49|
|Single source||Per Westermark||11/14/11 01:02|
|Just another chance.....||Michael Karas||11/14/11 04:46|
|If you read his entire post ...||Richard Erlacher||11/14/11 13:00|
|I have six other microprocessors that i found yesterday||Jacob Drake||11/14/11 13:12|
|Well, this is not the PIC forum ...||Richard Erlacher||11/14/11 13:37|
|I was just saying...||Jacob Drake||11/14/11 15:02|
|'found'stuff||Erik Malund||11/15/11 06:31|
|I have to agree, conditionally||Richard Erlacher||11/15/11 10:08|
|learning about microcontrollers||Andy Neil||11/14/11 15:24|
|Arduino is a very good choice if not going 8051 route||Per Westermark||11/14/11 16:54|
|Careful, now ...||Richard Erlacher||11/15/11 10:38|
|spend some $$$ on an already-assembled product||Andy Neil||11/14/11 15:14|
|in for a penny, in for a pound ...||Richard Erlacher||11/15/11 10:57|
|Still easier to learn to program before bringing up first hw||Per Westermark||11/15/11 11:26|
|I'm not so sure ... maybe we'll just have to disagree||Richard Erlacher||11/16/11 11:32|
|If you're really serious about this ...||Richard Erlacher||11/13/11 14:01|
|tools and such||Jacob Drake||11/14/11 09:58|
|Well ... maybe your Dad can fill you in on some details||Richard Erlacher||11/14/11 13:13|
|re: 8052||Andy Peters||11/14/11 12:57|
|Switched||Per Westermark||11/14/11 13:18|
|no offense, but that's incorrect.||Richard Erlacher||11/14/11 13:24|