How come there's so much after market support for the Gameboy?

[Magicantian]

As the title says, I see so much support for the Gameboy and the aftermarket mods for Famicom related is more limited. Is it somehow a tech spec thing or what?

I personally dreamed of getting involved in software development when I was a wee lad and I keep wondering also what is the best platform to develop on, GB, NES, SNES, Genesis.

Bucket list stuff you know?

[P]

I would say the Game Boy sold a bit more and therefore has a bigger audience, but when looking at the numbers it's hard to say as the Game Boy is very comparable to Famicom/NES in sales (both sold above 60 million units unless also counting GBC), so it might not explain it.

I guess the Game Boy may be more approachable today since you don't need a 15 kHz TV to use it. Only some batteries and you are good to go.



I have developed homebrew for all 4 of those consoles (except Genesis which I haven't really done anything except for very simple tests), though mostly for the Famicom/NES.
I highly recommend the Nerdy Nights tutorials, that's where I started and learned 6502 assembly from. The original forum posts on Nintendo Age are long gone with that forum, but it has been preserved here. There are also other like this one, but I suggest to at least check out the Nerdy Nights sound tutorial once you've learned the basics.

Once you can handle the Famicom, the Super Famicom isn't that hard to get into as it is similar, but it has a large number of hardware features that may seem daunting (mode 7 etc), so that's why I'd recommend to start with Famicom. The SFC's CPU uses the 65816 which is fully backwards-compatible with the 6502 but adds many new things and is a true 8-bit/16-bit hybrid (which is better than both 8-bit and 16-bit as it can work as either).
Check out Nesdev.org forums and wiki, it has the best NES dev wiki on the internet and now also a SNES dev wiki.

The Game Boy is a bit different from Famicom and uses a Zilog Z80-like CPU (recently identified as a Sharp SM83) which uses a subset of the Z80 ISA (Instructions Set Architecture). Learning Z80 isn't any harder than 6502, and once you know one ISA it's easy to learn another. I learned the Game Boy after the Famicom and before I learned the SFC.
Check out the GBDev Wiki (which is based on Pan Docs) and the forum of the same site. Nesdev also has a GB dev forum section.

The Mega Drive uses the Motorola 68000 as its CPU which is 16-bit but internally 32-bit. It is a bit more daunting than 6502 and Z80, so if you want something simpler but still want to go with Sega, I recommend the Mark III/Master System which uses a real Z80 CPU. The Mega Drive actually uses the Z80 as a sound co-processor and as the main CPU when in Mark III mode (like when you are using the Mega Adapter to play SMS games), so learning Z80 is useful for Mega Drive development as well.
For Master System check out the SMS Power forums and documents/wiki.
For Mega Drive check out Plutiedev.

Although all these systems all does their own thing, they all actually have many things in common as well, and learning one hardware makes the others easier to understand as you get more experienced.

[Magicantian]

High level response, it is so valued. You got me thinking!