Assembly Environment V0.8 released

mjallison42 · Post by **mjallison42** » Sat Feb 20, 2021 11:22 pm

Yep, it's a bug! Thanks for the report. I'll fix it in the next version.

mjallison42 · Post by **mjallison42** » Sat Feb 20, 2021 11:31 pm

By the way, in any prompt, pressing F8 will "escape" from the prompt.

John Federico · Post by **John Federico** » Sun Feb 21, 2021 6:12 pm

On 12/19/2020 at 1:45 PM, mjallison42 said:

Use the "view mode" to examine defined labels. This shows all defined labels , even outside of the program region. It is missing the ability to define a label outside of the program region.

Is defining a label/symbol outside of the program region something that will be added? I see that F2 (View) followed by F3 (SYMB) shows all of the symbols. It would be a nice feature to be able to define additional ones (maybe there already is and I just missed it?)

Also, there are times when I'm backing out of something and I hit F8 too many times and I end up exiting the program. Maybe make EXIT F12 instead of F8 - so that it is all the way at the end of the keyboard? ( and leave F8 as the BACK key for everything else, and have no other function assigned to F12?)

Fnord42 · Post by **Fnord42** » Mon Feb 22, 2021 4:06 pm

On 2/21/2021 at 12:31 AM, mjallison42 said:

By the way, in any prompt, pressing F8 will "escape" from the prompt.

Maybe I'm missing the obvious here, but why not use ESC for that?

mjallison42 · Post by **mjallison42** » Mon Feb 22, 2021 4:08 pm

I'd like to, but my experiments (using the emulator) don't appear to support ESCAPE. I need to check with the kernal guys to see if ESCAPE will be supported.

SlithyMatt · Post by **SlithyMatt** » Mon Feb 22, 2021 4:13 pm

It looks like STOP will be used in place of ESCAPE

Fnord42 · Post by **Fnord42** » Mon Feb 22, 2021 4:33 pm

Ah okay, a quick test shows that ESC and Ctrl-C both interrupt a Basic program, so it's probably mapped to the Stop key in the emulator. Using the WASD keyboard, RUN/STOP, 40/80 (and potentially RESTORE, but how do I check that?) don't work as expected. I suspect there's a reason for it, but is it a good reason? I imagine it might be a pain to get Scroll Lock key presses consistently on all supported platforms, or something like that?

mjallison42 · Post by **mjallison42** » Mon Feb 22, 2021 4:34 pm

Looks like I'll need to dig into the source and use a similar technique. Thanks for the tips.

Stefan · Post by **Stefan** » Mon Feb 22, 2021 7:44 pm

Hello.

I'm by no means an expert on PS/2 scan codes.

According to tables available on line, for instance here https://techdocs.altium.com/display/FPGA/PS2+Keyboard+Scan+Codes, it seems that the only key with prefix $E1 is the Pause/Break key.

The Esc key make code is $76.

Looking at the Kernal source at kernal/drivers/x16/ps2kbd.s

Keyboard scan routine starts at line 125

At line 132 it branches to line 177 (label: down_ext) if the PS/2 prefix is not 0

If the PS/2 prefix is $E1 we got the Pause/Break key

I have no working Pause key on my Mac, so I cannot test what happens. However, it seems that the X register is loaded with value #6 on line 205, which is moved to A register on line 208 and divided by 2 on line 209 before sent to the keyboard buffer. 6 divided by 2 is the code for the Esc key. So I would guess that Esc and Pause/Break is ending up doing the same.

The Esc key breaks Basic code.

In assembly programs, I would say that the Esc key doesn't have any function, other than what you tell it to.

The 8-Bit Guy · Post by **The 8-Bit Guy** » Thu Mar 04, 2021 5:47 pm

I'll probably be doing an update on the X16 in a month or two. It might be good to show this assembly environment off again. Has anyone written anything in the environment that would make for a good demonstration?