iKarith

Saturday is way easier for me than Sunday, so I'm up for it!

Signaling is going to be the same. I2C devices are pretty predictable.

Yes, the triple-rail unit is perfect for the TI—though Henry Courbis has the quad rail models that'd work well for most computers of the 1980s, so I'd be likely to get one of those so I have something to work with on other machines if it doesn't fit inside the console. I could always put it outside the console, but it seems if I'm going to have an external unit can probably find one pre-made.

Thought in case nobody had looked recently I should note the Mitsumi keyboard picture link is presently broken so that it may be addressed in a future update. This is really a very cool post Greg, since I've not said so before. When I got into the TI, I wish this had been there. Now it is.

My understanding is that a QI board is GROMs and a single jumper wire away from being 100% compatible with the standard board, so I'm very interested in this kind of thing. If you've got 120k free out on a 1284, you don't really need a 1284 for internal use unless you wanted to put an extended BASIC in the console. Which is not a bad idea actually. Hmm…

These days I only buy SanDisk and Samsung SD cards. Hey Matt, the OLED screen… How hard is it to support other resolutions? The 0.91" screens are a bit tough on my eyes. I saw a 2.2" 128x32 that's not bad. I saw a 2.8" 256x64 that'd be a lot nicer. I wouldn't object to pure pixel doubling. Apparently OLED character displays are now becoming common/cheap as a replacement for the LCD displays everybody's been using. That'd solve a few problems for me with the poor contrast of the LCDs, certainly!

I was thinking that this would likely fit inside the console. Of course it'd mean having mains in the console, and a switching PSU with caps that could carry a lot of voltage. A little caution with the underside of the board is called for. External is possible too, I just don't know what I'd do with the plug at the back for an external brick. DIN would make sense I guess?

Next version needs this ElectricLab!

I've seen a couple of very specialized (if somewhat similar) microcontroller-based cassette simulators, but I think it would be very cool to have a proper replacement for the cassette player for retrocomputing. I said to myself as I was thinking this, "okay, that's a digital voice recorder", except it isn't. Voice recorders tend to have far too complex an interface for the purpose in some respects and too simple in others. I think the right interface probably either looks like a shoebox cassette recorder at one end at least, or like an iPod from the appropriate generation with the added ability to record. What got me thinking about the iPod was how the wheel might be used for scrolling, scrubbing, and relatively quickly naming new recordings. I continue to believe Apple lost something when they got rid of that wheel interface. The one thing I'm sure of is that a replacement for the cassette recorder must replace a generic recorder and not be specific to a particular computer. That's what I've been seeing is a bunch of gadgets that replace a recorder for a specific machine.

Which chip do you normally use for that? GROMs hold 64k do they not? That'd probably require an ATmega1284P. Might a PIC18F27K40 fit? I'm sure it would if the GROMs were DIP24, but they're skinny DIP16s IIRC. Option #2 is much more ambitious: Some single chip that can replace both GROMs at once. That's still got the problem of the through-hole pins for the GROM sockets, unless you had something crazy involving a board with pins to fit both sockets on the bottom and pins to fit a one-sided board on the top with a QFP on it. That'd give you space, but it sounds janky. Also, you'd like as not different socket adapters for the original and QI boards. Likewise one for the /4. Messy.

There are a lot of landmines in this thread so I'm going to carefully not reply to anything but Omega's original post and therefore carefully avoid them all. *KABOOM* Right. There's always going to be a place for original hardware. I don't personally use floppy disks all that often anymore. In a couple of platforms, I have and want to maintain the ability to use them, but I don't personally have the space, the need, nor the inclination to mess with them usually. I just don't need them. But there are also people for whom the idea of using anything but those old floppies is just strange/weird. These older and newer technologies are redundant in that they serve the same purpose from the perspective of the TI console, but they're not the same thing in the eyes of many collectors and longtime fans of the system. Where you're going to start running into "redundant" technology is the stuff that was not contemporary to the machine. Do you need a nanoPEB if you have Matt's 32k/TiPi? Do you need a FinalROM/99 if you have a FinalGROM/99? Do you need the UDS-10 anymore? The UDS-10 is at least itself vintage technology, but it hails from almost a decade later. WiFi alternatives now exist, and there's TiPi. Can TiPi give you a serial port for things that aren't telnet though? Do you need that? I'd like to find good uses for some of this stuff, but I'm not sure some of these things really are obsolete now if you have the things that have supplanted them. The nanoPEB was a great thing in its day—or would've been if the QA was a little more consistent—but the number of reported problem units is said to have been high (my own required some repair before it came into my hands), and this coupled with hand-assembly by a single person just hurt availability. A person could've been very enthusiastic about it and less so a short time later as it becomes clear that the nanoPEB wasn't living up to those expectations. But having a nanoPEB that works well enough (it's an odd duck among nanoPEBs, doesn't properly fit the 3D printed case, etc), but TiPi is the better device to have given the choice, even for being more complex to set up and use.

I've wondered about the problem myself. I don't necessarily need to use the old EPROM chips, and actually I don't have an EPROM eraser either and would want one if I were going to do that. What I'd like though are some EEPROMs that work with modern programmers and replace the old EPROMs when you're done. Dunno if these exist. Probably via adapters.

The Raspberry Pi's got a fake RTC assuming you have a working Internet connection. It's actually easy to add a real RTC to any Pi using the I2C pins, which are not used by TiPi! I just wrote this review/setup guide. I dunno how the OLED screen a couple of people are using connects—if it uses I2C as well, you can still add this clock, but you'll need to chain the devices. I2C is a bus connection, so if that connector had stacking pins you could literally connect one straight to the other. It doesn't because it's trying to fit inside a Pi case, which it does! But it does appear to have pads you could solder the wires to for the next device (cable for the screen?) I'll defer to the electronics people on that.

There's also the idea of an aftermarket power supply for the TI. I'm seriously considering the idea of going that route still. Never know how long these old power supplies will last…

I would second Omega's assessment of the best way to get started. (Omega! You're green!) It gives you most of everything. You still need a tape recorder simulation for some things like Adventure and Tunnels of Doom, but Matt's 32k gets you well on to a permanent solution to that problem as well.

I don't know of a better contact cleaner, but other than contact cleaners rated for electronics, the only thing I use on PCBs is 90%+ isopropyl alcohol. I'm willing to use other things on non-PCB elements. Window cleaner gets a fair amount of use. Baking soda sometimes for cleaning textured plastics, though you have to go slow and easy since baking soda has some abrasiveness.

Omega, you should make a video about the DOS cartridge and what it does/adds/gives you. That might help encourage more interest in adding an extended BASIC to it.

Sunday is TERRIBLE for public transit in Beaverton. Since nobody lives anywhere near me really, I'd like to advocate for Saturday in the future. It'd cut literally half an hour off the one-way travel time, which puts it theoretically in the range that my sunscreen is supposed to pretend to work.

My plans got changed for me at the last possible minute, so I won't be there today. Family obligations. It's possibly for the best because it would mean an hour and a half out in the summer sun, and I can't really safely do that long out in the summer sun.

Hm, that's likely to be a problem as slow cards likely won't be produced forever. In fact, I'm pretty sure that at this point any you buy are essentially NOS.

If it's using modern components, it ought to be. You might need a different spacer for a snug fit.

Seriously thinking I need to stop buying cans of air and get myself a small compressor. I worry about static charges that way though with anything I can afford.

Maybe there'll be a SAMS card for Matt's expansion connector at some point. Then it'd sandwich in between the 32k and TiPi. Or possibly replace the 32k? I dunno how the SAMS card appears on the bus.

Erik's card will unfortunately conflict with TiPi most likely.

I know how they work on Atari and other systems—they don't work that way on the TI without modification, and the button controllers may not work at all on something that doesn't put 5v on pin 5. (Atari standard puts it on pin 7, which powers the 74LS157 incidentally.) Greg's got these 6 button controllers wired up using buttons other than B as joystick 2's inputs. He can define 5 buttons and a start and mode button I suspect he's not using at all. I was wondering what he's got A, C, X, Y, and Z mapped to on the second joystick port.