99/4A connection to HDMI question

[GamerTut]

Hi

I have a 99/4A that I’d like to connect to my A/V system.

 

Are there any reliable devices to connect the 99/4A to HDMI or other interface?

thanks

[+OLD CS1]

Yes, but YMMV.  This is mentioned in several other threads.  (I will get with @arcadeshopper about adding links to them in the FAQ thread.)

[pixelpedant]

Well, I decided I’d do a write-up on the situation re: processing/displaying TI-99/4A video signals in the present day, since this comes up pretty often, in exactly the same way.  And I haven’t seen any in-depth analysis here on the subject lately. Probably because no new devices relevant to this have hit the market since the RetroTINK-2X, and since F18As haven't been available for some time, so there's not much new to talk about. In any case, I figured it'd be good to have some detailed info on hand I can copy-paste where needed in the future.  So I decided to tackle the subject in detail here.  

 

The Situation:

 

Without modification, NTSC TI-99/4As output Composite video in keeping with the non-standard field structure common to video game and computing devices of its era, where those have been designed for use with a television.  This signal is handled with varying degrees of success and non-success by mainstream consumer electronics not purpose-built to deal with it, and is handled optimally by a few select specialised video processing devices purpose-built to deal with this corner case and related ones.  Since this signal is available at the external a/v connector of the NTSC TI-99/4A, all that is needed to access it is the proper cable. And these are widely available (as well as easy to make).  

 

Other cases involving different signal types include PAL TI-99/4A units, which outputs YPbPr at the a/v port, and F18A modded TI-99/4A units, which output VGA (RGBHV) video, at a user-installed DE-15 connector.  But both of these are rarer cases.    

 

Solution 1: 15KHz CRT Monitor (i.e., “tube TV”)

 

 

Much of the time, the cheapest solution for correctly displaying a TI-99/4A’s video signal of course be a CRT TV.  If you don’t have one, you can usually find one for free. And it’s exactly what a TI-99/4A was built to use. That having said, if you want to display a TI-99/4A’s signal on a digital screen, or connect it to a digital capture device, options exist.  

 

Solution 2: LCD with Composite Input

 

 

Some HDTVs (especially Sony and Samsung units) feature Composite inputs, fairly respectable upscalers, and good “game modes”, which do a respectable job of minimising lag, turning off undesirable post-processing, and cleaning up the signal, where signals like the one produced by the TI-99/4A are concerned.  However, HDTVs will often be undesirable as displays for the TI-99/4A, if it is being used as a computer (rather than a living room game console). Some cheap generic mini-LCDs feature Composite input, and would more so serve its use as a desktop computer. However, as with any generic standalone upscaler, performance will usually be poor, with significant lag and dropped frames.  

 

Solution 3: Wait for the F18A MK2

 

 

A new iteration of the TI-99/4A's drop-in replacement VDP, providing more modern signal output is in the works.  However, level of availability and ETA is as yet unclear.  More information and discussion can be found in the thread here.

 

Solution 4: Upscaler Featuring HDMI or VGA Output Compatible with a Modern LCD

 

Options here are organised by ascending price categories.  This is a far from comprehensive list. But it is a list of some popular devices used in this area, with which I have personal experience (at least as far as processing video from an F18A modded or unmodded NTSC TI-99/4A goes - I do not have a PAL TI-99/4A).  

  

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Device: Generic Composite->VGA or Composite->HDMI Adapters

 Purpose: Converting Composite video from an NTSC TI-99/4A to a signal usable by a modern LCD or capture device.

Price: $10-$20  

Source: Amazon, Ebay, etc.    

Results: Widely varied.  Lag is generally significant.  As well, half of all frames are typically dropped, due to the signal being treated as interleaved (i.e., standard NTSC video), which it is not.  Some do fail to output a signal or output a defective signal, under these conditions. Quality is usually poor.  

 

 

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Device: Extron DVS 304

Purpose: Converting Composite video from an NTSC TI-99/4A or YPbPr video from a PAL TI-99/4A or VGA video from an F18A-modded TI-99/4A to RGB video (either RGBS or RGBHV as preferred) at a desired output resolution (up to 1080p).

Price: $40-$80

Source: Ebay/Auctions

Results: Good.  Lag is minimal (one to two frames).  Post-processing features are good, and do a reasonable job of tweaking a messy signal in easily understood ways (e.g., brightness, contrast, sharpness).  Can be managed and tweaked via RS232, which some will find appealing, but the front menu accesses all core functions. A reasonable, and now reasonably priced, solution for upscaling Composite video, for use with a device accepting VGA input.  The ability to match a display device’s native resolution (i.e., rather than simply line doubling) is always nice.  

 

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Device: RetroTINK-2X

Purpose: Converting Composite video from an NTSC TI-99/4A or YPbPr video from a PAL TI-99/4A to line-doubled HDMI.

Price: $89.99

Source: RetroTINK and certain resellers.

Results: Excellent.  Lag is essentially non-existent.  Frames are not dropped. The upside and downside is that this is an “it just works” solution.  So if you’re looking for that, you’ll get it. But if you’re looking for tweaks and post-processing adjustments to clean up a messy signal or fix colour issues or what have you, these are not on offer here.  Also, the output will not be at an LCD’s native resolution, but at 480p, so you will be at the mercy of the device’s own scaler, as well.  

 

 

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Device: OSSC

Purpose: Converting VGA video from an F18A modded TI-99/4A to HDMI output or YPbPr video from a PAL TI-99/4A to HDMI output.  

Price: €110.00

Source: videogameperfection.com 

Results: Excellent.  A high quality transcoder and upscaler with abundant options and negligible lag.  Does not support Composite input, so this is not a solution relevant to unmodded NTSC consoles.  Exceedingly rich signal tweaking toolset, so this will appeal to users who want to make fine adjustments to signal handling/timing/post-processing and like getting their hands dirty.  

 

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Device: Micomsoft Framemeister

Purpose: Converting any and all signals relevant to all unmodded TI-99/4A models (save RF) to HDMI output.

Price: $400-$450

Source: Solaris Japan

Results: Excellent.  This is the best all-in-one “it just does everything” scaling solution for converting legacy 240p, 480i and 480p signals to HDMI on the market today (and for some time now).  It does not directly handle 31KHz RGBHV, however, so it is not directly a solution for F18A-modded TI-99/4As.  Though it can be turned into one fairly easily/cheaply with the help of a sync combiner, as it handles RGBS.  However, its handling of Composite and YPbPr input is unmatched, and comes with a fairly rich, and fairly easy-to-use collection of tweaks.  This was built as an (albeit fairly expensive) general consumer device, and so options and settings are mostly fairly intuitive, and do not demand an advanced knowledge of legacy a/v terminology, etc.  Nonetheless, it will also offer a rich collection of tweaks and customisations to the advanced user. Support for a vast array of output resolutions and settings guarantees that native resolutions and timings will be available to output devices up to 1080p.  This device can even be used to apply secondary tweaks to an already transcoded and digitised signal, as it accepts (and scales/post-processes) HDMI input. So TI99->RetroTINK->Framemeister or TI99->OSSC->Framemeister are signal processing paths which have their use cases.