What was first, CTIA or GTIA?
In the old days, I thought that GTIA was, naturally, an enhanced version of CTIA that was developed later. I also understood that for some reason GTIA wasn't ready on time, and for this reason the earliest computers shipped with CTIA.
But there are were some comments here that this wasn't exactly what happened. It was mentioned that GTIA and CTIA were developed in parallel, and some claims that GTIA was even earlier. Furthermore, there are reports that the very first computers actually shipped with (a faulty) GTIA? Well, I can't argue too much about the historic sequences. There are other people that are far more qualified than me. But I believe, I do can comment about what can we conclude looking, technically, at the chips.
After having seen die shots of both chips, it is almost sure, that GTIA (as we know it), is a post CTIA development. GTIA is not just an enhanced, (mostly) compatible CTIA. It is a patched CTIA. Not only they modified the CTIA schematics, without making new schematics from scratch. They also patched the CTIA layout (the layout is the physical silicon level of the chip). And if GTIA is (sort of speak) a patched CTIA, then it must have been implemented after CTIA. Btw, there are no traces, that I can see, of disabled GTIA like functionality in CTIA.
But please note that this doesn't, necessarily, contradicts the idea of an earlier GTIA. Conceivable, there was another GTIA, (may be even named differently), that was developed earlier. Conceivably, that earlier GTIA was actually shipped in some computers until Atari found out it wasn't working correctly. But if this is true, then the GTIA we know was a later, separate development, based on the CTIA schematics and layout, discarding the (hypotetical) earlier work.
In the old days, I thought that GTIA was, naturally, an enhanced version of CTIA that was developed later. I also understood that for some reason GTIA wasn't ready on time, and for this reason the earliest computers shipped with CTIA.
But there are were some comments here that this wasn't exactly what happened. It was mentioned that GTIA and CTIA were developed in parallel, and some claims that GTIA was even earlier. Furthermore, there are reports that the very first computers actually shipped with (a faulty) GTIA? Well, I can't argue too much about the historic sequences. There are other people that are far more qualified than me. But I believe, I do can comment about what can we conclude looking, technically, at the chips.
After having seen die shots of both chips, it is almost sure, that GTIA (as we know it), is a post CTIA development. GTIA is not just an enhanced, (mostly) compatible CTIA. It is a patched CTIA. Not only they modified the CTIA schematics, without making new schematics from scratch. They also patched the CTIA layout (the layout is the physical silicon level of the chip). And if GTIA is (sort of speak) a patched CTIA, then it must have been implemented after CTIA. Btw, there are no traces, that I can see, of disabled GTIA like functionality in CTIA.
But please note that this doesn't, necessarily, contradicts the idea of an earlier GTIA. Conceivable, there was another GTIA, (may be even named differently), that was developed earlier. Conceivably, that earlier GTIA was actually shipped in some computers until Atari found out it wasn't working correctly. But if this is true, then the GTIA we know was a later, separate development, based on the CTIA schematics and layout, discarding the (hypotetical) earlier work.