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**Forgotten** · January 28th, 2003

Like I said a billion times, I will not write the link/multiplayer/netplay code. If someone wants to write, go for it.

Why is it easy to add link for PSX/N64/Genesis/Master System/SNES ?

Those systems are designed to have multiple players in one console: one console, multiple players. Kaillera for example is used to transmit the player movements across the internet and that's how it works.

TGB Dual which most people mention has link code, actually emulate two GB machines in your computer, where the second one represents the remote player and it only transmits the joypad movements.

GBA is a lot more complicated than most people think: it requires a physical cable between the machines. Timing has to be extremely accurate or link connection will break. The communication is not a simple movement of keys: it usually contain a lot of game specific data and it can be done at 1 or 2 Mbit/s.

It is really hard to emulate the link hardware and its timing over the network. It would be possible to take the TGB Dual approach, but most computers would not have enough CPU to emulate 2 GBAs at the same time.

Other than that, it is pretty easy to send packets to the internet and the hardware of the GBA link is not hard, it is the timing and the ammount of that can be transferred at a time that makes it really almost "impossible" to do.

As I mentioned before, any email on the subject is automatically deleted by me without response.

January 28th, 2003	#15 (permalink)
Forgotten Emu author Join Date: Oct 2001 Posts: 483	Like I said a billion times, I will not write the link/multiplayer/netplay code. If someone wants to write, go for it. Why is it easy to add link for PSX/N64/Genesis/Master System/SNES ? Those systems are designed to have multiple players in one console: one console, multiple players. Kaillera for example is used to transmit the player movements across the internet and that's how it works. TGB Dual which most people mention has link code, actually emulate two GB machines in your computer, where the second one represents the remote player and it only transmits the joypad movements. GBA is a lot more complicated than most people think: it requires a physical cable between the machines. Timing has to be extremely accurate or link connection will break. The communication is not a simple movement of keys: it usually contain a lot of game specific data and it can be done at 1 or 2 Mbit/s. It is really hard to emulate the link hardware and its timing over the network. It would be possible to take the TGB Dual approach, but most computers would not have enough CPU to emulate 2 GBAs at the same time. Other than that, it is pretty easy to send packets to the internet and the hardware of the GBA link is not hard, it is the timing and the ammount of that can be transferred at a time that makes it really almost "impossible" to do. As I mentioned before, any email on the subject is automatically deleted by me without response.