apersson850

I once wrote a driver unit for accessing the clock on the Triple Tech from UCSD Pascal.

My expansion box is full now. Interface card RS 232 card 32 K RAM expansion card P-code card Real-time clock card I/O card RAMdisk card Disk drive controller card

Fortunately they don't fit in countries with more modern electric systems.

Good, then it works on 60 Hz without any problem. No worries, then. I just wanted to make sure you were aware of the potential risk, so you don't put anything on fire.

Now note that if the TV set is rated at 50 Hz only, nothing says it will run at 220 V 60 Hz, which it will be when used in the US, with a simple 1:2 transformer in between. Depending on the design of the power stages in the TV, the impact could be anything from none to disasterous. I have no way of assessing the possible effect on your TV, but the risk is there.

Swedish citizenship?

"Tomorrow" would be my first choice, since I by chance will spend the weekend in Texas. Not Austin, but closer than I normally am.

That shouldn't make any difference, provided the VCR works. Inside such a modulator, it's usually possible to fine tune the channel it uses. That's intended for television sets with fixed channel steps, where tolerances may imply that the two devices can't perfectly match their channels. If the TV looks at channel 36.3 and the modulator outputs 35.8, some fine tuning is necessary. I've never needed to do that, so I can't say for sure if, and then how, you do that with the TI modulator.

The RF modulator for European consoles is supposed to emit an antenna signal, tuned to UHF channel 36. That antenna signal should include both the image and the sound. You can look at a picture of such a modulator. The channel number is printed on the label. This particular one has been modified to output composite video and sound on two separate coax ports (one BNC and one RCA connector).

I've only used my home-made RAM-disk to keep the SYSTEM.EDITOR, SYSTEM.COMPILER and SYSTEM.FILER when using the UCSD p-system. Since that operating system relies quite a lot on swapping these files in and out, it makes a big difference. Only recently have I added two Horizon RAM-disks, but not done so much more than figuring out why the ROS 8.xx didn't support the p-system. Got it going, but I'm not doing much with my TI nowadays.

A monitor which supports both PAL and NTSC is, by defninition, independent of the mains frequency. Otherwise it wouldn't be able to support both versions of input, at least not without moving it from the US to Europe, for example. I've never seen any such monitor that couldn't accept both inputs regardless of the mains frequency. One could imagine that PAL would only work with 50 Hz supply, and NTSC only with 60 Hz supply, but no, I've never seen that. And it's Hz, not hz. Units named after people start with a capital. So it's A for Ampere and Hz for Hertz, but m for meter and s for second.

Well, CALL KEY is for BASIC, of course. But the keyboard unit 4 returns keycodes in the way they are mapped for the p-system. So the keyboard unit 4 is supported by the system's keyscan procedure, in order to make it easy for the p-system to check the keyboard and get the keycodes it expects. As it's in the system, you can call it from BASIC too, but not really giving any added benefit there. Originally, keyboards 1 and 2 are left and right side, 3 is for BASIC and 4 for the p-system. When the 99/4A was introduced, with lower case letters, unit 5 was added to provide lower case in BASIC too.

There have been similar software written for programmable calculators, to find the position of single objects, within a reasonable time. So dependent on your use, it may work.

I've made a modification to my PAL UHF modulator, so I get composite video out of it. Not as good as RGB, but better than antenna signal.

Yes, of course, write precompensation. Not write pulse. It's too many decades since I worked intensly with the WD2793...

Does the text near the top variable resistor say WPW? Write Pulse Width, or whatever that could be?

To run the printer spooling, I'd presume. Don't see any other reason.

Not really related to the problems here, but just in case anybody would ever need one, I once wrote a unit in Pascal, to be able to use the Triple Tech clock in the p-system.

The CorComp controller (mine has the WD2793 controller) does support both single and double density. There was also a program upgrade for the card, which made it's functionality better, but didn't affect the data storage itself.

The drives that were delivered as standard drives in the IBM PC, before hard drives became the norm, also works. I have two, labeled IBM on the front, but made by Shugart, in my secondary expansion box.

You can always create the file(s) to load yourself, without using the SAVE utility. I've used the program format to store memory images I've created myself, with a different program.

I don't know, of course, since I didn't do that. But I have a theory. When doing touch typing, your start position is with four fingers on your left hand on the ASDF keys. Your right hand will start on the JKLÖ (on a standard Swedish keyboard) keys. On a TI 99/4A, it's the JKL; keys you rest your fingers on. With the original TI 99/4 layout, your pinky will "fall short", as only the JKL keys are present. Maybe this false key was glued there by somebody, who felt that he wanted a key to rest his last finger on, even if it was a false key.

The alpha lock diode thing was the first modification I did to my console. Over time, more would come...

I only have two, or so I think, but both have at least the keyboard swapped for a grey one.

To decode the GROM to work from the module address space must be the right thing to do. I concur.