The Ultimate Retro Chip Tester?

a few weeks ago we covered an arduino-based tester for two types of dram move over and make room for the retro tip tester professional which tests hundreds of different chips although that comes at a cost hello and welcome back to noel's retro lab today we're going to be looking at the retro chip tester professional which lies in the opposite end of the spectrum from that arduino dram tester we saw a while back this one sports a huge list of supported retro chips including some unexpected kinds too but before we can review it we need to build it because it's sold just as a pcb and when you order your chip tester professional you get this you get two beautiful pcbs and you get an atmega microcontroller already solder in and that's a good thing because for a lot of people that will be enough to be put off by the project this is by far the most difficult thing to solder so it's great that it comes already soldered and i imagine tested the rest of the things are all very straightforward through whole components but we don't have any of them this is not a kit this is just the pcbs and the microcontroller so first things first we need to go and buy all the components the retrotip tester professional comes with a very detailed and long bill of materials there's nothing hugely expensive or exotic there just lots and lots of components so definitely plan for some time if you're going to order them separately at the start of the build materials page there's also a link to a pre-populated card so that can be really handy if you're going to order it from there keep in mind there are a couple of items that are not in the cart and make sure you read the warnings in the manual carefully unlike some people i know and finally here they are all the necessary components i hope i hope we don't start with this and i find that i'm missing some of them i did my usual trick of printing the bill of materials and then i was able to for now just check that i have each of them so this is multiple pages of them and so with this to the side we're going to start soldering the components we need to talk manuals right now i admit i'm not usually a big manual reader especially not ahead of time but this is something else the manual for the retrochip tester pro is amazing 141 pages full of illustrations and pictures and everything you could possibly want to know about it we'll get into more details later but it starts out with a very detailed assembly section with pictures of the process which is extremely useful a suggested assembly order and even some tips and things to watch out for along the way since i'm going to be putting multiple resistors at once what i'm going to do is i'm going to put it in this pcb holder and that will make it easier to put all the resistors with their legs through and then flip it and solder it all at once for things like this it's really handy to keep this interactive bill of material pcb explorer thing right now i was looking for r 75 our 220 ohm resistor so you just click on it and it highlights the place on the pcb for you which is really handy when you have this many [Music] components [Music] after i got this far i very proudly posted a picture of my progress so far i know it's not much but i was just happy to finally get started with this project that had been sitting on the back burner for so many months it was then the 8-bit museum the designer of this board just looking at the picture pointed out that i had bought the wrong zip socket oops and he was right of course the expected socket has a thin middle bar so you can use both wide and narrow chips he even warns that about in the manual but i didn't notice until then so i scrambled and i bought another socket online but come in locally so it arrived in just a few days just to find out that it was the wrong kind again apparently it's not uncommon with this kind of sockets to have one picture online but to receive something else great i've placed a couple more orders hopefully one of those will work but in the meanwhile i had a friend send me one of the correct model for sure hopefully it will get here in time for this video but unfortunately that wouldn't be the only problem i would have with components in this project let's do a quick montage and see how far i can get with the build [Music] the next step is to program the firmware on the atmega microcontroller and for that that's why we have those pins in there that's the isp i think stands for in system programmer and so we need a device that connects here and a computer and it can transfer the firmware unfortunately all of those are slightly different so i had to buy one just for this one so apparently this one dymx avr avr is a type of microcontroller this one fits right here and then it has a usb connector for the laptop and that's good we have a power light in here and it detected com5 programming the atmega involves two different passes the first one is called programming diffuses which is some non-volatile state on the microprocessor which determines how the chip will act the retrotype tester pro includes a script to do this pretty much automatically just by answering a few questions so that's quite convenient however one of the problems of relying on scripts like that is that sometimes things don't go quite right and you just march on like i did here right off the bat it tried confirming that communication with the microcontroller was working and reported an error but i didn't even notice that even when it came time to actually program the fuses i still thought it was working correctly and while there are no big error messages printed you can see that it still can't verify the add mega signature so it should come as no big surprise that when i went ahead with the next pass which is actually programming the firmware it failed completely at this point i went ahead and learned how to use the program to interact with the microcontroller by hand and i tried just reading the fuses back but nothing it looks like the microcontroller was totally dead this is kind of a worst case scenario and i was afraid i had bricked the microcontroller and there was no way to recover from this without desoldering the microcontroller and putting a new one which i'm definitely not looking forward to doing so i got in touch with stefan the designer of the board and he was extremely helpful with suggestions of things to check it turns out a lot of the suggestions were already in the manual under the troubleshooting section towards the end remember i said i'm not a very big manual first person anyway that included some on how to recover from a non-responding microcontroller which is what we have here depending on the fuse configuration the add mega might be driven either by a clock signal or by the signal from an external crystal oscillator like the one we have here if the wrong value was set on the fuse the microcontroller might not be working at all because it expects a full clock signal so in that case we can try jump starting it like if it was some kind of old car by providing a fake clock signal so here comes arduino to the rescue this is a super simple program that simply generates a square wave signal on some of the output pins that we can use as a clock signal to jump start the app mega we're going to jam it right on top of the oscillator signal and hope the microprocessor picks it up i've already loaded the program here so this should be active already and we're going to drive specifically this pin right here so because it's actually pretty snug i've just put the um the connection right under the resistor making contact in there and then we can use any of those ports between 8 and 13. so i'll just grab that one so now i'm going to plug in the programmer and let's see if we can program the fuses there you go it just did it that's excellent so actually that didn't work that was an error message that we got in there so let's try it again apparently this is normal because the clock signal is not perfect so sometimes you just need to try it a few times and now it really passed now we have a bunch of writing and reading and it looks like it's verifying that those values are correct so i think that worked now and now with the arduino disconnected and just the programmer let's try flashing it now it's working that's great okay i think we may be done this is a good time to mention that you can also buy the retro chip tester pro already flashed with the correct firmware which could save you some of this trouble however stefan is constantly updating the firmware adding new chips and improvements so even if you get it flashed you may want to learn how to do this procedure to keep up with improvements and finally the moment to test it for the first time so i'm going to put the lcd screen in place like that yeah holds itself okay right now i'm just going to power it with nine volts in here and i don't have the extra power board that's whenever we want to start generating other kinds of voltages like plus 12 or minus five so i'm gonna turn it on and well this turned on and this turned on and i see on the power supply that we're drawing very very little current although wait you know what it is i think i saw something like this in the manual i think this adjustable resistor controls the contrast on the lc just like the lcd on that amstrad ppc that tricked me once won't let me trick me again there we go nice so yeah that's that's perfect like that this is awesome this means it's working and here are all the components for the power board this should be a lot easier after having done the full main board and finally the correct socket arrived [Music] so here we are finally ready for the first test as soon as we turn it on we get the starting menu and then immediately we move on to the selection of the chip you want to test because this is not a tester for one type of memory or two types of memory like we saw last time with the arduino tester this tests hundreds and hundreds of different chips so the way this works is a little counterintuitive to me it's um we'll talk about more about it later but the idea is that the hundreds of chips in this machine can test are all in a sequential list so by pressing select you move on to the very next chip in that list so right now we're in the 214 static ram and then if i press next it moves to the 6550 static ram so if i wanted to go somewhere to some eprom that maybe was towards the end of the list i would have to just press this a long time or just leave it pressed however it has also the jump button which lets you jump to the next section in that list so if i press jump so it doesn't look like anything has changed but apparently the 3101 is the beginning of the next section of the static ram list and i think if i press again i go to the dram section no not yet okay so like i said it's not the most intuitive thing in the world so again okay so now we're in the dram section and i don't know if i press it again whether there will be multiple dram sections in the manual he has a very clear list with all the sections and all that it almost feels that for this to be really effective i should print that out and keep it next to the machine once you're within the section that you want then you can press select and you can move on to the next one so if i wanted to go to the 40 4164 which is a very common chip here we're at 4116 so i imagine 441 say 4164 but right now if i pressed okay we could go ahead and test that one of the things that is kind of crazy to me is that if i press select again to see maybe there's another option with this oh network four four six four i want to go back to four one six four you can't there's no back button as far as i know there's not even a combination of these guys that will go back one that to me is totally crazy it feels like it would be so much more usable if i had another button to go back by far i think the ideal interface would be a rotary controller and an ok button with a rotary controller it lets you move back and forth really quickly and i would make this sub menus so i would make sram dram whatever thing comes next those are the things you select in the top level once you press ok you go in that level and then with the rotary dial you select the different models within that category and if not a back button would be awesome so for the tests i'm going to be coming here to my boxes of dram sram and these are the 74xx logic chips we'll have lots of examples there and then for something that is supposedly not working we'll reach over into the box of shame that you've seen before this is where all dead chips go this is i guess the chip graveyard so let's start with one of the most common dram chips at least the 4164 those are the ones that we've tested before with the arduino tester one really nice thing about this tester i believe is that it doesn't power anything here until you press ok you know what let's test it i like testing things so ideally we should not be seeing 5 volts right here perfect yep and then once we start the test i'm sure all those transistors are driving the right power to the right pins i'm going to press ok and now it's testing it and right away we're getting feedback here which is really good i definitely like to see what it's doing and this is not just a status bar feedback said check in zero it was writing all zeros and reading all zeros now it's telling us that it's actually writing all ones and reading all ones and now it's doing an alternating pattern zero one zero one so we know it's alive and we even know what it's trying to do and when he fails we'll know why he failed so that's actually super cool to have more insight into the tests that are happening it's even doing a random read-write test and the blink rate of this slow down a little bit which tells me this is going to take a little longer so those are actually the exact tests that i had in that source code that i wrote for a quick arduino test which makes sense just as a bare minimum zero one alternating ones and zeros the other way around and random okay it makes a beeping noise test passed and asking us whether to do it again so that's great so instead of changing chip types right now i'm actually going to give it a faulty 4164 oh there we go so this one i have it marked as faulty but look at that right now it's writing zeros and reading zero is okay there you go and now oh this must be address so maybe at address 1000 hex it returns a one instead of a zero and that's not like it matters i mean we're going to throw this away no matter what but the fact that this happens at address 1000 probably tells me that this is an addressing issue and that is failing because that's the first time we set that bit to access a particular memory cell so that's very interesting the kind of information that it gives in there so let's try a more interesting dram chip which is the 4116 and this is more interesting because it needs not just 5 volts and ground but it needs minus 5 volts and plus 12 volts so this is where this power board is going to come in handy if it's working correctly i guess we're about to find out interesting i heard the relay click so obviously that's what those are for to relay the -5 and plus 12 to the to the chip area perfect it passed and now let's give it a non-working for 116. i imagine this is going to go quick boom okay very cool you see that is why it's good that the power is disconnected i grabbed this chip and as i grabbed it i dropped it and put it like this if it was powered pretty much bad things would have happened so i'm very glad this is powering up only at the time of the test let's try something different this is probably the most exotic or for me anyway dram that i have in my box this is listed as mcm so motorola 514256 i know this is a 256k times 4 bits when you have a chip like this and you don't know exactly what option to select you can use the interactive ic database provided with the documentation we can type the markings on the chip and it tells you what kind of chip it is and the specific name and section to use for the testing that's super handy and it brings us to the 44256 or the 256k times four bits and let's test it this is probably gonna take longer i imagine because there are many more bits in there wow that took several minutes but hey it passed and that's not a dig against the tester i really i don't think you could go much faster than that with the amount of tests that it did on the 256 k times four bits that is not an insignificant amount of memory the strength and the most unique thing about this tester is the kind of chips that he can test so let's get a little bit more exotic when i grab some of these static ram these are mcm6810 these are static rams used on the ti-994a so this is only 128 bytes well that was very quick that was only 128 bytes so i expected that and what about logic chips we have lots to choose from let's start with some easy ones so hey i was just using the 7408 and gate the tests for this should be instant yep doesn't say anything i guess it will say failed if it failed i have a bunch of logic tests in here that are supposedly failing so let's grab one of them for example here's a 74 hcu04 and wow that's taking a long time okay so it's interesting with the logic chips it's not printing success or failure and i actually just realized why we're not seeing the results when we test a logic chip because i didn't follow directions properly and i got the wrong screen this is supposed to be a 20 by 4 lcd or oled screen it's a 16 by 2 so no wonder things are getting cut off sometimes and we're totally missing two lines so i'm even shocked that we managed to get this far and here's the right part this is pretty obvious once i put him side by side that this is the correct one and that also explains why this wasn't going all the way to the edge i'm like oh that's kind of weird that there's that space well yeah because i chose the wrong screen okay and there it is with the support and i think it's really cool that the interface to both screens is identical even though the screens are significantly different i think it's just really cool that they're literally plug and play let's turn it on and yeah there you go look oh interesting so this is the information we're missing earlier there was something saying mode most chips so imagine that's because we're only seeing a selection of the most commonly used chips and we can change that to have all of the chips but that's a lot of them also it tells us that for the currently selected chip it tells us where ground and vccr so that's that's an extra protection so you can double check things but anyway let's go back and check our 7408 perfect so now it really says chip okay again that's the bit we were missing i wonder if we're missing much with the dram tests that i did let's do one really quick let's see how it works oh there you go we have a nice progress bar in there that before we had that zero there in telling you what kind of test it was doing but then the bar tells you how far it is in that test so that's a great great feedback something that i wished for in the other dram tester excellent yeah definitely use the correct screen size it's also worth mentioning that the retro chip tester professional supports a huge variety of chips much more than i've had a chance to show here the manual lists the full table and it includes things like fifo rams bipolar roms pals and even some soviet chips and wait it doesn't end there you can define your own parameters for your own custom rams and there are even adapters available to be able to hook up sims and many other devices so it really works with a huge amount of formats so finally let's try a category of chips that we haven't tried yet which is roms and eeproms i'm going to try reading these amstrad roms that i have right here and interestingly this comes preloaded with the knowledge of several common roms i doubt this is one of them but first of all let's find out so these are 16 kilobyte roms i know that just because this is the floppy disk controller rom on the amstrad cpc6128 and so because it's 16 kilobytes is i need to select the eeprom equivalent of a 27c 128 oh wow check it out it is support it it doesn't say that is the floppy disk drive one but that's good enough i mean that's that's fantastic that it says that so the next step is well wouldn't it be great we just read it wouldn't it be great to actually get that data we can do it because this is not connected to anything but we can connect it to an sd card module and that's what we can use that for and obviously i need an sd card and so now pressing and holding the ok button tells you that we want to do a dump not just a crc there we go saving it gives us another progress bar okay it tells us that it's created on the disk and yeah it tells us again that it's an amstrad rom so that is super handy and how much does the retro chip tester pro cost all in all the pcbs and microcontroller are sold at cost which come out to be around 36 euros plus shipping the components if you order them from the store with a pre-made card come out to be around 40 euros already including shipping i have no doubt you can find them cheaper on places like aliexpress or ebay but apart from the risks of getting incorrect or counterfeit parts chances are you're going to spend close to the same amount of money you'll just get many more spares for each part which is not necessarily a bad thing for the extra parts not in the cart like the lcd and the zip socket it's probably around 6 euros just don't do it like me and make sure you get the right ones the first time and finally the usb isp programmer was 23 euros although you could use the arduino directly and save yourself some money in any case that brings up the total to about 110 euros so the big question is is it worth it there's no doubt that this is a very complete and very well designed device my only real complaint about it is the user interface but other than that it's really really good the variety of chips the feedback during the testing the reporting of the errors it's all really good it also addresses head on some of my other concerns about the other chip testers by providing a protection to the microcontroller from faulty chips and by not turning on the power until the test starts it really is fantastic however all of that comes at a cost the obvious cost is the price because at 110 euros it's not exactly an impulse purchase the hidden cost is the time and effort to assemble it ordering the part building it testing it flashing it and if you are like me ordering the correct part again it's all part of a fun extended project but don't underestimate the effort required so in the end is it worth it if you only repair a few machines a year or you mostly work on the same kind of machines then it may be hard to justify getting this device i personally do a lot of projects with a variety of machines so i'll be constantly using it so if you're like me then it's a fantastic device well worth the amount of effort to put it together so that's it for today i'm hoping to review other chip testers in the future so stay tuned for those i hope you enjoyed this episode and as usual let me know what you think in the comments and i'll see you next time [Music] if you enjoyed this video please consider supporting noel's retro lab on patreon or joining the membership on youtube not only is that the best way to support this channel and allow me to continue making more videos but you also get some extra perks like early access ad free videos and more thank you again to all the supporters see you next time

Channel: Noel's Retro Lab

Views: 101,319

Rating: 4.9395857 out of 5

Keywords: chip tester, dram, sram, rom, eprom, 74xx, logic chip, atmega, microprocessor, soldering, bom, pcb

Id: _99HNsxgLRw

Length: 26min 57sec (1617 seconds)

Published: Thu Jul 29 2021