68kMLA Classic Interface

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Recreateing the Apple TechStep
Posted by: sarnau on 2023-01-31 15:56:35 I can confirm that the code is indeed matching a HD44780 (16x4). BTW: It defines 8 custom characters (the up/down/up-down arrow, Apple Logos, etc). So, that should make things easier for you 🙂
Posted by: jajan547 on 2023-02-01 04:30:48 I have confirmed modern LCD's with the HD44780 compatible controllers do work fine on the techstep 🙂 I thought I had posted that in this thread but I guess not... Must have only mentioned it in PM's with @jajan547 Here is the techstep working with a modern backlit LCD (Which looks much better than the original LCD!) View attachment 51788 I love how sharp and clear these newer displays are, I'm thinking about putting one in some or all of my current TechSteps.
Posted by: max1zzz on 2023-02-10 16:21:39 All I have to say is this:
Posted by: jajan547 on 2023-02-10 18:56:12 All I have to say is this: View attachment 52230 She's looking great!
Posted by: demik on 2023-02-13 11:59:55 Whoa, good job ! You are a machine
Posted by: joshc on 2023-02-13 12:40:31 Looks great. What are the plans for the case?
Posted by: max1zzz on 2023-02-13 13:40:01 Whoa, good job ! You are a machine Thanks 🙂 I'm very happy with how it has come out and was certainly not expecting it to boot on the first try! Looks great. What are the plans for the case? Thanks 😉 Case will probably be something 3d printed but we haven't really decided yet, this may not even be the final form factor as this design was mainly done to be easy to test I have however got the LCD module mounted properly which makes it look much more like a TechStep Now that's done I can do some proper testing on it
Posted by: Chuckdubuque on 2023-08-04 09:49:15 @max1zzz I'd love to see any update on this project!
Posted by: pizzigri on 2023-08-05 09:09:34 Actually me too! And would even love a kit!
Posted by: max1zzz on 2023-08-06 10:01:39 @max1zzz I'd love to see any update on this project! Actually me too! And would even love a kit! I need to get better at updating these threads.... It basically done 🙂 (at least as far as it is going to be taken for now) the clones have been tested and work on everything we have tried them on. Only issue I came across during testing was that the clone was failing to get some macs into test manager mode via SCSI (Macs that used the ADB entry method always worked fine) however all scsi tests would run successfully once the mac had been manually put into test manager mode. After a it of head scratching I remembered a tidbit form the datasheet of the Logic version of the 53C80 (which was the one I was using) that it ran faster internally than the AMD / NCR 53C80's, perhaps this was a timing issue? Swapping the Logic part for a AMD or NCR part fixed this issue proving this was the case I currently have two clones sitting on my desk that are about 99% complete, just waiting for the display modules to come in I could possibly make up kits in the future if people are intrested, need to rectify a couple of small issues on the PCB's that currently require some trace cuts and patches first but the next run of PCB's will have these all fixed so would be a good candidate for this 🙂
Posted by: olePigeon on 2023-08-07 15:05:35 Do 68040 based machines have a Test Manager mode? Would it theoretically be possible to make a 5th ROM pack for testing Quadras and Centrises?
Posted by: jajan547 on 2023-08-07 18:35:07 Do 68040 based machines have a Test Manager mode? Would it theoretically be possible to make a 5th ROM pack for testing Quadras and Centrises? It’s possible but would require a good bit of work and testing to reach a stable usable image. I agree would be very cool to see a 5th. It’s too bad Apple killed it shortly after the color classic and LC520
Posted by: aplmak on 2023-08-15 17:05:45 This is just absolutely amazing! Great work!!
Posted by: max1zzz on 2023-10-02 13:56:53 Update time! First batch have all sold and a second batch of PCB's are in production The design has been changed slightly to stiffen up the units when assembled, the port pack and keypad are now one PCB with the LCD screwed into the centre of it, this also has the added advantage of getting rid of the LCD cable which will simplify assembly a little Additionally DIP footprints have been added for the EEPROM's for storing test results which give us more assembly options if we can find a EEPROM that works here. These will also have a backplate with them (essentially another blank PCB) to protect the bottom of the logicboard from shorting on the unit you are working on and also providing a space a lithium flat cell could be installed in if you don't want the 18650 on the keypad board Also I have had some interest in kit versions of these, if anyone else is interested in this please let me know. The kit version will be a little cheaper than the assembled units but please don't expect them to be half price or anything like that as a very large proportion of the cost of these is the parts and not assembly time (I expect kit for to be somewhere around £200 vs £250 for the assembled units however the exact price will depend on the exact BOM cost once I have everything ordered)
Posted by: LaPorta on 2023-11-27 08:17:31 So…where can I learn how to use this, and what is it useful for?
Posted by: jajan547 on 2023-11-27 08:19:54 So…where can I learn how to use this, and what is it useful for? It’s a work in progress @max1zzz has updated the PCBs and sold the first few prototypes. This is a great tool for testing Vias, sound chips, scsi interface, cpu, and rom status, and even voltage. Works the same as a TechStep normally would except you select which rom variant through DIP switches. there are four ROM that each Cover a range of certain computers.
Posted by: Chuckdubuque on 2023-11-27 08:25:31 Yep. I bought one of the prototypes and have been using it. Detected a bad SCSI chip on a battery-bombed but otherwise ok IIci board. Runs a lot of low level tests (depending on the machine). Documentation here (originally scanned by janjan547)
Posted by: LaPorta on 2023-11-27 08:32:24 Yep. I bought one of the prototypes and have been using it. Detected a bad SCSI chip on a battery-bombed but otherwise ok IIci board. Runs a lot of low level tests (depending on the machine). Documentation here (originally scanned by janjan547) Thanks guys, that’s exactly what I was looking for. Definitely will look into one.
Posted by: activepilot on 2024-01-10 06:04:20 Amazing work @max1zzz and @jajan547! Would you consider open sourcing the designs and the dumped firmware?
Posted by: max1zzz on 2024-01-10 06:22:19 Amazing work @max1zzz and @jajan547! Would you consider open sourcing the designs and the dumped firmware? Thanks 🙂 Opening up the designs is something that will be considered in the future but is not something we can do right now
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