Modding PS1 DualShock controller possible?

It is possible to mod the controller to work with all PS2 games?
From what I understand the controllers (dualshock 1 and dualshock 2) are the same but what make the difference when some ps2 games doesn't work with the dualshock 1 controller?

 

The DualShock for the PS1 lacks pressure sensitivity, which isn't a problem for most games since it wasn't utilised too much. But for games like Metal gear Solid 2/3 it's essential, so you will need a controller with pressure sensitivity (like the DS2).

 

I don't think anyone's made a compatibility list. Certain games lockout dualshock 1 despite no confirmed use of dualshock 2 specific features, but it'd be a pain to extensively test the ps2 library to be sure which.

 

And Gran Turismo 4

 

I *think* TimeSplitters doesn't allow the original PS1 DualShocks to be used. Could be wrong though, as it's been a few years since I tried (didn't have 2 x DualShock 2s at the time)

Regarding the mod, I guess you'd have to salvage the parts from a DS2 anyway, so might not be worthwhile.

 

One of the Blade games also tells you that you need to connect a Dual Shock 2.

 

The only Blade game on the PS2 was Blade 2, and I remember that one well... you're right that it asks for a DS2, but it's just a pointless "lockout" for this game, not a technical restriction since it didn't use pressure sensitivity at all.

 

So, the DS1 have some lockout and technical restrictions on ps2 games?
I was thinking that something hardware was changed from DS1 to DS2 including the pressure sensitivity that ps2 games verify.

 

I know Valkyrie Profile 2 does this as well. I think the GTA games used the pressure sensitive buttons as well.