From the Pervasive web site:

Pervasive.SQL V10 "Summit"
Pervasive PSQL Summit v10 supports both the 32-bit and 64-bit editions running on a supported 64-bit operating system and x64 processors with either a 32-bit or 64-bit application.

Pervasive.SQL V9.5
Pervasive PSQL v9.5 and higher supports applications running in 32-bit mode on a supported 64-bit operating system and x64 processors.

Pervasive.SQL V9.1 and earlier
Pervasive PSQL v9.1 and prior (including Pervasive.SQL V8) support applications running in a 32-bit mode on the supported 32-bit operating systems and x64 processors.


More information
Visit the Pervasive knowledge base article here


Using Service Accent on a 64 bit CPU
Please read the following article:

Title: Service Accent compatibility with Microsoft Windows Solution ID: 0404231425525