The Parts-Bin Approach: Konami’s Contra
nicole.express
nicole.express
Contra was an early experience that made the propaganda of everyday life visible to me.
The author seems to have arrived at the answer later in the article:
I assume these opaque parts codes were meant at least in part to make things a little harder for bootleggers. Sure, you can’t stop them, but you can slow them down.
Custom parts are difficult enough to RE, but a common trick was (and to some extent still is) to grind off the markings on common parts. Remember that this is in the 80s, where large databases of ICs, sortable by pinout, were basically nonexistent.
Ironically, with the degradation of search engines today, IC part numbers and markings have gotten far more difficult to find too, since there are now so many more companies making parts but search engines are barely indexing them. One wonders if that's a deliberate move from anti-right-to-repair advocates.
https://www.patreon.com/posts/49965048
I wish Ken Sherriff would do decap teardowns of these chips.. I emailed him the request, but it's a longshot. In the past he has not replied to me (no hard feelings on my end, surely he's very popular and busy).
Was it cheaper to make custom hardware in that era?
You'd select from a few templates depending on how big a die you needed, or any distribution of special features like sram blocks, etc. And on this die would just be a giant grid or sea of gates, not wired together besides power and clocking.
Then you would use the vendors tools to take your logic (in schematic format or very early HDL like ABEL) and they would generate a routing solution using 2 metal layers of interconnects to wire all the gates together.
Then you could order a few tens of thousands of chips, and the fab would put your 2 metal layers on top of the silicon and package it.
The cost was honestly not bad at all. NEC's prices ran about $50k of tooling (not including any software or design tool rental) which is peanuts. The per unit cost was higher than fully custom silicon though.
Companies offering gate arrays were NEC, Toshiba, Ricoh, Fujitsu, Sharp, and so on.
By the early 2000s this started to wane and NEC started pushing more incentives to keep the business going but now they much less common. There were services that would take a working FPGA design and handle the conversion for you.
Gate arrays were a stepping stone in the journey of integration and consolidation.
If you want to read more, look up a NEC Semiconductor Solutions Databook from the 90s.
There are very many in Japan if you look at Wikipedia's list: https://en.wikipedia.org/wiki/List_of_semiconductor_fabricat...
They're phasing out gradually. I work for an IC company and we're retooling some mostly-analogue parts from 10+ years ago onto modern processes because the right sort of fab is increasingly hard to find.
I suspect that even if you dig an old GDSII file out from the nineties for one of those chips it may be hard to find somewhere to make it without requiring tweaks.
Now that's SEO!
It was the only way to win . . .
You know when you beat Contra, it restarts you at the beginning with your remaining lives. After beating the game 3 times in a loop without the Konami code, I decided I was done with it and turned it off.