Previous Thread
Next Thread
Print Thread
Page 3 of 3 1 2 3
Joined: May 2009
Posts: 2,045
Likes: 84
J
Very Senior Member
Offline
Very Senior Member
J
Joined: May 2009
Posts: 2,045
Likes: 84
Originally Posted By shattered
Emulating actual DVK series would require changes to T11 core -- their microprocessors (1801VM1, 1801VM2 and 1801VM3) are ISA-compatible but have subtle differences.


Now that (almost?) all of the CPU cores have been converted to proper modern devices, implementing device-specific opcodes should be as simple as abstracting those opcodes behind member functions and then overriding them in a child class.

Joined: May 2012
Posts: 554
Likes: 1
S
Senior Member
Offline
Senior Member
S
Joined: May 2012
Posts: 554
Likes: 1
EIS instruction set would be the first to add, since vm2 has it built-in and ROM code relies on that.

Joined: May 2012
Posts: 554
Likes: 1
S
Senior Member
Offline
Senior Member
S
Joined: May 2012
Posts: 554
Likes: 1
The 11 had a lot of CPU variants and instruction set extensions -- https://sourceware.org/binutils/docs/as/PDP_002d11_002dOptions.html

So T11's one is "baseline" + "Limited EIS" + "MxPS"; full EIS also has ASH, ASHC, MUL and DIV.

1801VMx extensions are briefly described here -- http://pdp-11.ru/mybk/doc/PDP11.TXT, there's also a full technical manual.

Joined: May 2012
Posts: 554
Likes: 1
S
Senior Member
Offline
Senior Member
S
Joined: May 2012
Posts: 554
Likes: 1
Hey, someone does actually use ie15 driver to play Tetris smile Tetris itself runs in SIMH, though.

https://www.reddit.com/r/MAME/comments/8l0jiq/mame_mess_any_way_to_hide_the_row_of_words_and/

https://www.youtube.com/watch?v=xrZYJ5Bn-xg

Page 3 of 3 1 2 3

Link Copied to Clipboard
Who's Online Now
1 members (judge), 26 guests, and 2 robots.
Key: Admin, Global Mod, Mod
ShoutChat
Comment Guidelines: Do post respectful and insightful comments. Don't flame, hate, spam.
Forum Statistics
Forums9
Topics9,090
Posts119,149
Members5,014
Most Online890
Jan 17th, 2020
Our Sponsor
These forums are sponsored by Superior Solitaire, an ad-free card game collection for macOS and iOS. Download it today!

Superior Solitaire
Forum hosted by www.retrogamesformac.com