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Robbie Hatley <Hatley.Software@gmail.com>: Mar 04 05:31PM -0800 At my workplace, I'm often faced with circuit boards which WOULD be repairable, if not for the fact that the CPU on the board is fried. (These CPUs are not like the CPUs in PCs; they're 15mm-square $5 8-bit 8MHz 100-pin CPUs with 25 pins on each side, surface-mount soldered directly to circuit boards.)   Repairing these boards is maybe impossible, but I'm investigating options. The 2 main problems that would have to be solved are:   1. Remove CPU from board. (CPU doesn't need to survive, but board does.) Heat gun? (Might damage surrounding components.) Solder bath? (Might unsolder surrounding components.) Cut pins? (Might damage traces.) OTHER???   2. Extract software from good CPU??? (The board maker won't supply the software due to copyright issues. The boards DO have programming headers, presumably for use with an external programming module which connects to a PC via USB; but I don't know if such programmers can work in reverse, READING software from a CPU instead of WRITING to it.)     Anyone here have some ideas regarding these two issues?     -- Robbie Hatley Hatley dot Software at gmail dot com

"jfeng@my-deja.com" <jfeng@my-deja.com>: Mar 04 05:52PM -0800 I suggest investigating ChipQuik. Do a Google search, and look at the videos. It looks like you can get it from Digikey, Mouser, etc.   Disclaimer: I have not used it myself, but was amazed when I saw it demonstrated.

John Robertson <spam@flippers.com>: Mar 04 06:23PM -0800 > I suggest investigating ChipQuik. Do a Google search, and look at the videos. It looks like you can get it from Digikey, Mouser, etc.   > Disclaimer: I have not used it myself, but was amazed when I saw it demonstrated.   ChipQuik works as advertised, however I think you might further ahead by investing in a hot air or Infra-Red/Hot Lamp service system. These start fairly cheaply and, depending on what you board looks like, can be pretty easy to run.   If only a few boards, then ChipQuik is probably best, otherwise hot air or IR is the way to go for chip replacement.   The question is - how many boards are we talking about and what is the replacement cost? A good hot air system will cost a few hundred dollars but can simplify the chip replacement process considerably.   I'd start by watching some youtube demonstrations of "hot air chip replacement" to get an idea of how it is done.   John :-#)#

Michael Terrell <terrell.michael.a@gmail.com>: Mar 04 06:56PM -0800 On Wednesday, March 4, 2020 at 8:31:42 PM UTC-5, Robbie Hatley wrote: > don't know if such programmers can work in reverse, READING software > from a CPU instead of WRITING to it.)   > Anyone here have some ideas regarding these two issues?     I used to replace Motorola MC68340 processors fairly often. I used solder wick to remove most of the solder, then an Ungar Loner soldering iron with a .015" tip, along with a tiny curved pick. I would apply a slight pressure to a pin, as I touched it with the soldering iron tip. It would op free, and the pic would remove enough heat that it stayed free from the pad. It took really good soldering skills but both the board and the IC were undamaged. These were 288 pin, 72 per edge. The programming port was JTAG, not USB.   As far as reading the firmtware, you didn't give a part number. Some have a bit that can be set to stop you from reading out the firmware.

Ralph Mowery <rmowery28146@earthlink.net>: Mar 04 11:34PM -0500 In article <r3pkpr$fk2$1@dont-email.me>, Hatley.Software@gmail.com says... > Solder bath? (Might unsolder surrounding components.) > Cut pins? (Might damage traces.) > OTHER???   Can't help with the programming.   To remove the chip, a hot air gun is the way to go. There are 2 ways to help keep the air where it is wanted. Special tips that are just large enough to blow the hot air on the pins. Use some kapton tape over areas where you do not want the hot air. It is usually like an amber colored celophane tape and is heat resistant.   It depends on your budget and how many boards you plan on working on. There is some hot air stations on ebay for around $ 60 that may get the job done. There are better ones that are a couple of hundred bucks. Having a good stereo microscope helps. An Amscope se400z scope with 10x lenses is very good for the price at around $ 200.   There are plenty of youtube videos that show how to do it. Just get some old computer boards with smd on them and practice. Plenty of flux is one of the better tips.   Plan on spending around $ 350 to $ 400 to get the minimum equipment needed to do a decent job. The microscope and hot air station is the most.

Rob <nomail@example.com>: Mar 05 02:42PM > don't know if such programmers can work in reverse, READING software > from a CPU instead of WRITING to it.)   > Anyone here have some ideas regarding these two issues?   That kind of chips is actually EASY to handle, compared to the newer style BGA where you only see a square chip directly mounted on the board and no pins whatsoever. See the other replies.   The problem will be the programming, you need to investigate that first. Programmable CPUs usually come with a readback prevention and when that is activated (it is an option during programming) it will be difficult or impossible to get the software, and then the whole replacement thing is not a topic anymore.   What is the part number of the CPUs?

Fox's Mercantile <jdangus@att.net>: Mar 04 10:44AM -0600 On 3/4/20 10:05 AM, Arlen Holder wrote: > Why do I, as the recipient of his cowardly bullying, have > to endure him?   That should be self evident, but I don't expect a cunt like you to figure it out.     -- "I am a river to my people." Jeff-1.0 WA6FWi http:foxsmercantile.com

Arlen Holder <arlen.george.holder@is.invalid>: Mar 04 09:14PM On Wed, 4 Mar 2020 08:33:08 -0800 (PST), RosemontCrest wrote:   > You are among the latter who is not adding value.   FACT: *Peter Wieck has never added any thread of any adult value on this ng* *in the entire history of Usenet!*   If he did, absolutely _nobody_ can find it.   And yet... o Adults will notice cowardly bullies can't pass the test I already passed.   Not one of them can point to a _single_ thread, in the entire history of Usenet, that shows _they_ have added a thread of on-topic technical value.   *Not a single one of the cowardly bullies can pass the _simple_ adult test.*   And yet, cowardly bullies try to diffuse this simple pertinent evident fact:   FACT: *Peter Wieck has never added any thread of any adult value on this ng* *in the entire history of Usenet!*   That's simply the fact of this thread. o Prove that evident fact wrong instead of attacking the bearer of facts. -- That's simply a fact that the bullies hate; but it's _still_ simply a fact.

Arlen Holder <arlen.george.holder@is.invalid>: Mar 04 09:23PM On Wed, 4 Mar 2020 10:44:06 -0600, Fox's Mercantile wrote:   > That should be self evident, but I don't expect a cunt like > you to figure it out.   Hi Snit,   You can change the subject matter all you want with childish bullying.   Right now, we're simply proving outright the evident fact that Peter Wieck has _never_ in the entire history of Usenet, even _once_ posted a thread to this newsgroup of _any_ adult on-topic technical value whatsoever.   If he has, _nobody_ on this planet can find it. o Can you find it Snit?   FACT: *Peter Wieck has never added any thread of any adult value on this ng* *in the entire history of Usenet!* -- If he did, absolutely _nobody_ can find it.

RosemontCrest <b23sunwoodllc@gmail.com>: Mar 04 03:51PM -0800 On Wednesday, March 4, 2020 at 1:14:28 PM UTC-8, Arlen Holder wrote: > On Wed, 4 Mar 2020 08:33:08 -0800 (PST), RosemontCrest wrote:   > > You are among the latter who is not adding value.   > FACT:   You are a narcissistic troll who adds no value whatsoever. Return to underneath the rock from where you came.

John-Del <ohger1s@gmail.com>: Mar 04 03:58PM -0800 On Wednesday, March 4, 2020 at 4:23:22 PM UTC-5, Arlen Holder wrote: > *in the entire history of Usenet!* > -- > If he did, absolutely _nobody_ can find it.       I don't often say this, but why don't you indeed get the fuck off the group and stay off. No one here gives a shit about your butthurtness. Get some Preparation H and a turkey baster and relieve your pain as well as your burden of ignorance.   You'll find few friends here.   It's funny that you think Peter bullied you. Just because what he says is beyond your understanding doesn't make it bullying.

Fox's Mercantile <jdangus@att.net>: Mar 04 06:34PM -0600 On 3/4/20 3:23 PM, Arlen Holder wrote:   >> That should be self evident, but I don't expect a cunt like >> you to figure it out. > Hi Snit,   Still think I'm snit do ya?   Bwahahaha, and I still think you're an ignorant cunt.   The difference is, I'm right, and you're wrong.     -- "I am a river to my people." Jeff-1.0 WA6FWi http:foxsmercantile.com

Phil Allison <pallison49@gmail.com>: Mar 05 12:17AM -0800 Arlen Holder wrote:   --------------------   > o "pfjw@aol.com" <peterwieck33@gmail.com>   > If so, please post a link to a thread he opened of on-topic added value: > o ?   -------------------------------------------------------------------

Phil Allison <pallison49@gmail.com>: Mar 05 12:27AM -0800 Arlen Holder wrote: --------------------- > Has Peter Wieck ever added any technical value to any thread on this > newsgroup in his entire life? < > o "pfjw@aol.com" <peterwieck33@gmail.com>   > If so, please post a link to a thread he opened of on-topic added value: > o ?   ------------------------------------------------------------------

Arlen Holder <arlen.george.holder@is.invalid>: Mar 05 01:18PM On Wed, 4 Mar 2020 18:34:51 -0600, Fox's Mercantile wrote:   > Bwahahaha, and I still think you're an ignorant cunt.   Hi Snit,   Thank you for proving, by what you post, _exactly_ what you are. o Usenet is so much more valuable & pleasant, when people act like adults.   FACT 1: *The fact remains clear Peter Wieck has never in his entire life ever* *added even a _single_ thread of on-topic technical value to this ng.*   Not even one! o If he had, someone, somewhere, would have been able to locate it.   FACT 2: *And yet, Peter Wieck incessantly craps all over other people's threads.*   Those are just facts which anyone can refute if they can _find_ a thread. o Why can't anyone find even a _single_ thread of value from Peter Wieck?   Why is Peter Wieck's _only_ contribution to shit on other people's threads? -- Only 2 types post to Usenet: Those who add topical value & those who can't.

makolber@yahoo.com: Mar 04 10:20AM -0800 > > Why not just to the one where the branch circuits all connect (if different from where the meter is)?   > What happens when that one wire opens? A bad neutral is a very common fault. Then you have no place for a fault current to go. RIP!.   Its even worse, if that one wire opens disconnecting the machine from the neutral/ground, the case of the machine can become electrically live because current will flow through the load to the ground/neutral.   Anyone touching the case could be shocked.   m

Jeff Urban <jurb6006@gmail.com>: Mar 05 01:00AM -0800 >As usual, you are wrong.   Mm Hhm.   You say what you want Means nothing.

makolber@yahoo.com: Mar 04 10:02AM -0800 If the logic is CMOS, you could also have an OPEN input someplace.   I have seen these change state seemingly at random due to static electricity.   m

Cursitor Doom <curd@notformail.com>: Mar 04 10:07PM >If the logic is CMOS, you could also have an OPEN input someplace.   >I have seen these change state seemingly at random due to static electricity.   Well, this is certainly the time of the year for plenty of static - if you're in the northern hemisphere anyway. ;-)

Jeff Urban <jurb6006@gmail.com>: Mar 05 12:57AM -0800 >I think you need to be more careful with the advice you're dishing >out here. The cathode on this tube runs at -2850VDC with the anode >at only +84VDC. Please don't generalise about the tube potentials on >these pieces of test equipment. Someone else may read your remarks >on Google a year or more in the future and end up killing >themselves.   So he is supposed to read your fucking mind ? MAKE, MODEL, CRT NUMBER, are you sending that telepathically or what ?   My TV is broke. It has no make or model but it has c1 to 5154, which one is bad ?   ANSWER ME ! What is wrong with this TV ! COME ON, WHAT IS TAKING YOU SO LONG ? I transmitted my phone number to you five seconds ago. CALL ME AND HELP ME THIS IS A TV.   Go ahead, ANYONE tell me how much of an asshole I am, that will certainly prove something. And you go ahead and read minds, I won't because there is nothing in them.

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