I need a 6532 to restore my old genuine AIM-65.

I also have a few tubes of NMOS 6502 and some non-WDC 65C22 that I will never find use for myself. Even a few non-WDC 6551 with working TX IRQ. Not sure if they are NMOS or CMOS. I'm an invalid and has difficulties to check right now. If there are ...

Retrocomputing requires a genuine CRT monitor for the right feeling from old times.

I use a little B/Wchinese TV bought new for SEK249 (about USD25), sold out as useless when analogue transmissions ceased. It was easy to add composite input and the tube produces a sharp image. Of cource generated ...

It worked out that the best solution was to have a manual close signal initiated from the PC that flushes the buffer and close the file. The 816 can of cource also initiate this from new programs that are aware of that files needs closing.

Now to the next issue, that was slightly unexpected.
Using ...

The machine now seems to work nice and stable, so I'm going on to make programs for it.

One of the first tasks is to allow something else than tape to be used to store/load using the built in commands. The AIM monitor program has the "U"ser option for device. The character output has to be blocked ...

That is a toy, not a scope. Not recommended. With it's low sampling rate it will just show interferences between that and the signal You try to measure. In short, 100% pure crap.

Ali has locic probes, I have no idea about performance or build quality. F.ex. the one below. Just search logic probe ...

Don't let this very minor problem drift away. Here in Sweden we hava a saying "to make a hen out of a feather"...

You most likely have a bad reset. to be good it must be one clean transition and not came too early.

The reasons for that are the display's intermal reset functions that take some ...

Make this to work is not rocket science. The fact that it sometimes works tells that it's likely correctly wired, but someting is marginal. The single display line with dark squares is typical for a non initialized 44780 and tells that the display module likely works. The need for power cycling to ...

I will see if I can do the test ASAP and also test with a higher clock.

Did the old 800nm Sanyo contain dynamic circuitry?

I have searched quite a lot for errata, but turned out negative. The faulty chip has an uncommon(?) date stamp of 9906, but is bought directly from WDC around 2003 so it's ...

A new MPU has arrived and the JSR (ABS,X) problem has departed. Everything looks fine at the scope, the JSR "lands" spot on the intended target. The instruction is re-inserted where it was ment to be when all this trouble started and everything works perfectly!

Hopefully the computer will be OK now ...

A given set of information, like f.ex. a program, has a given entrophy. It's as impossible as a warp drive to represent it with less. Take a good look on what is written about information theory already during the 1950:th. Even if it takes one word to command the execution of a complicated task, the ...

Testing with a hardwired $FC just takes 8 resistors, but I don't want to force those into the sockets and risk damage.

There will soon be another MPU available and that will be the next to try.

As can be seen on my first test to find out where the JSR "landed", that was done in native mode with wide A and short indexes. The problem was still present.

The actual bank settings may have an effect. My program is running from bank0 with all new registers left in reset conditions. As my ...

If I had another MPU on hand, it would of cource already had been tried. I have two on order since a week or so from Mouser. Hopefully I get them before the big holidays that are coming up now. They will almost for sure also be made at the Sanyo plant. If those too fails in the same way, I will ...

Here we go again, this time with new chinese scope probes and a marker on the other channel to incontrovertible identify the machine cycles. The marker is an unused output of the IO address decoder. The signal shown is bank/data 0.

00173 0b100 24 45 indadr .da $4524

00237 0b33a af 04 40 08irq lda ...

The picture shows the last activity before a very long 0 level. It's taken with delayed time base and I'm very convinced it shows just the JSR (ABS,X). When I get one more working probe I will repeat the test with a marker by addressing one of the unused I/O-addresses in the instruction before. With ...