In MAME (release 0.207), the following TI hardware is emulated:

Computers:

  • TI-99/4
  • TI-99/4A
  • TI-99/4A QI
  • TI-99/8
  • TI-99/2
  • Geneve 9640

Peripheral devices:

  • Peripheral Expansion Box
  • 32K Memory Expansion Card
  • TI Floppy Disk Controller Card
  • BwG Floppy Disk Controller (SNUG)
  • Enhanced Video Processor Card (SNUG)
  • Hard and Floppy Disk Controller (Myarc)
  • Horizon Ramdisk (Horizon)
  • High Speed GPL Card (SNUG)
  • Memex Card (Myarc)
  • Memory Expansion Card (Myarc)
  • P-Code Card
  • SuperAMS Memory Card (Asgard, SW99ers)
  • Speech Synthesizer plus PEB adapter
  • RS232/PIO card
  • IDE Adapter Card (Nouspikel)
  • USB/Smartmedia Adapter Card (Nouspikel)
  • Handheld controllers (Joysticks)
  • Bus mouse (EVPC, Geneve)
  • Mechatronics Mouse
  • Remote Handset Controllers (TI-99/4)
  • Floppy Disk Drives
  • Hard Disk Drives (generic and Seagate types)
  • Cassette recorder
  • Cartridge Expander

Media

  • Solid State Software cartridges
  • Cassettes (wav files)
  • Floppy disks images
  • Hard disk images

 

Inhalt folgt noch

To be continued

Der TI-99/4A ist ein Heimcomputer von Texas Instruments, und für diejenigen unter euch, deren Haupt noch nicht völlig ergraut ist: Ein Heimcomputer war in den 80ern das, was heute der PC ist. Die Technik war natürlich wesentlich einfacher gehalten, aber wir hatten damals viel Spaß daran, lernten das Programmieren, wurden auch kreativ, und Computerspiele gab es auch schon.

What is MAME?

MAME (Multi-Arcade Machine Emulator) is an emulation framework that allows for emulating a broad scope of computing devices, particularly arcade machines, but also computer systems. For a through discussion of MAME, see the MAME website.

As I owned a TI-99/4A computer back in the 80ies, my special interest is, of course, the emulation of the TI computer family. This is not just the TI-99/4A console and its peripheral expansions, but also the TI-99/8, the Geneve, the TI-99/2, and some more exotic things.

In MAME, quite a lot of features have already been realized; here is a list of features.

How does it look like?

Emulation cannot be like the real thing, people usually say. Well, have a look. Here is a short clip showing the game Parsec in action, emulated on MAME 0.207. Notice the graphics, the sound, the speech synthesis, and the speed that pretty well matches the real system.

This is another well-known game, TI Invaders

These samples are taken from the 60Hz version (NTSC); if you are used to European consoles (50Hz), the above scenes may look too fast. Indeed, the European users always had some advantage when competing in a game because there was no compensation for the slower video clock.

System requirements for the TI family

To run MAME, and in particular the TI emulations, your host (PC, Laptop) must offer a minimum performance. You might wonder why a PC with gigahertz CPU may run into trouble when emulating an 80ies computer with 3 Megahertz clock, but the point is that MAME emulates the electrical circuits at a fairly precise level, and while in your real system, lots of things may happen in parallel, this is not the case in emulation.

Here are some tests that show you what you can expect. The percentages show how well the emulator managed to keep pace with the real system. Only when you have a 100% result, the emulation runs at the precise speed; otherwise the running time is stretched. One may also say that the numbers say how much work it has managed to do when the real system did 100%.

The number in parentheses represent the performance when the "Spectre-V2 mitigation" is effective. This vulnerability particularly affects Skylake/Kaby Lake CPUs (6* and 7* families).

(MAME release 0.207, March 2019)

  Speed GHz TI-99/4A TI-99/4A + EVPC SGCPU aka TI-99/4P Geneve TI-99/8 + HX5102 TI-99/2 + HX5102
Raspberry Pi3 B+ 1.4 6% 4% 4% 4% 4% 5%
Laptop Celeron 2.0 19% 14% 15% 14% 10% 16%
Thinkpad T60 Core2 Duo 1.8 92% 89% 91% 85% 45% 91%
Laptop Core i5-3320M 2.6 100% 100% 100% 100% 100% 100%
 PC Core i7-6700K 4.0 100% 100% 100% 100% 100% (85%) 100%
PC Core i7-7700 3.6 100% 100% 100% 100% 100% (86%) 100%

 

I am quite sure that the Raspberry Pi3 B+ was not running by optimum conditions, and there may be some tricks to get a better performance. Still, the MAME emulation is a heavy weight, and you can easily imagine that the fact that your Core i7 PC pulls more than 200W of electrical power, while the Raspi just needs 15W, should have a visible effect.