Wiki editing discussion | MSX Resource Center (Página 160/194)

Por gdx

Enlighted (6429)

06-06-2022, 12:06

Manuel and me have already talked about this. Only some cartridges have these mirrors.

About ASC8 and ASC16, this is just a contraction. I found it in several texts and even in OpenMSX source code.

Por Grauw

Ascended (10820)

06-06-2022, 12:20

gdx wrote:

Grauw wrote:

In the ASCII16 section of the wiki, it says:

Page (16kB)                        Switching address             Initial segment
4000h~7FFFh (mirror: C000h~FFFFh)  6000h (mirrors: 6001h~7FFFh)  0 (0Fh for R-Type)
8000h~BFFFh (mirror: 0000h~7FFFh)  7000h (mirrors: 7001h~BFFFh)  0

But the switching address mirror ranges make no sense to me, the mirrors for 6000H overlap with 7000H, and the mirrors for 7000H are claimed to exceed 7FFFH into page 2, which is unexpected to me. It does not match msxnet’s documentation.

Manuel and me have already talked about this. Only some cartridges have these mirrors.

So how can address 7000H be a switching address (mirror) for both pages at the same time? That’s impossible, it would be dysfunctional. Which page does 7000H switch?

And are you saying that if I have an ASCII16 cartridge, I can use the mirrors to switch banks for the 2nd page using an address in the 2nd page directly (e.g. 8000H), without first needing to access the 1st page slot to access the switching address? Do all ASCII16 mappers work like that?

The msxnet documentation also claims ranges are *000-*7FF instead of *000-*FFF as the wiki does… Another discrepancy, which makes me distrust the information.

I checked openMSX briefly and it seems to me that RomAscii16kB.cc and RomAscii16_2.cc are implemented in the ranges as msxnet describes them.

Por gdx

Enlighted (6429)

06-06-2022, 12:18

There is probably a copy/paste error for the mirrors of the switching addresses. (fixed now, thanx)

Por mars2000you

Enlighted (6556)

06-06-2022, 12:18

gdx wrote:

About ASC8 and ASC16, this is just a contraction. I found it in several texts and even in OpenMSX source code.

I think it would be better to use ASCII8 and ASCII16, as they are more used than the contracted versions.

Por Grauw

Ascended (10820)

06-06-2022, 12:19

gdx wrote:

There is probably a copy/paste error for the mirrors of the switching addresses. (fixed now, thanx)

Ok, thanks! I didn’t want to just make a change myself without asking, since I don’t know all the details of the many different mappers that are out there in the wild.

Por Manuel

Ascended (19677)

08-06-2022, 09:22

gdx wrote:

About ASC8 and ASC16, this is just a contraction. I found it in several texts and even in OpenMSX source code.

Only in the text we got from Manuel Pazos describing the MFR SCC+ (SD), which we quoted in the emulation code. So it's not really used in openMSX itself at all. I propose to stick to the clear names ASCII8 and ASCII16.

Por gdx

Enlighted (6429)

08-06-2022, 12:14

I've often seen ASC8 and ASC16 in Japanese docs since the 90s so I'm used to them but you can replace by ASCII8 and ASCII16 or even ASCII 8K and ASCII 16K if you prefer. It does not matter.

Por T.R.

Resident (45)

08-06-2022, 17:22

Question: the page on the JVC HC-95 states that "there's a 6th version for cable TV, the HC-95(H) with built-in 40MB hard disk drive" but it looks like a reference for this claim is missing. Where does this information come from? I'd be interested to know more.

Por sdsnatcher73

Enlighted (4288)

08-06-2022, 20:55

Yeah the odd thing is that the NMS8260 wiki page mentions that JVC harddisk and interface but there is also noted it was not released in the HC-95.

Por mars2000you

Enlighted (6556)

08-06-2022, 21:12

I think I got this info from msxholder, but I ignore his source.

The NMS 8260 page was written before this new info. Besides, it's not contradictory as the H version was not released for the general public. There's also a difference between 2OMB and 4OMB btw.