The default configuration of the Commander X16 Developer Edition has 512KB of High RAM. Most applications and games will work within 512KB, but there are some cases where more RAM may be desirable. Future system releases may have only 512KB of RAM, but the Developer Edition is upgradeable to allow for more complex environments used by developers and power users. Likewise, the USER VIA IC (65C22) will allow the use of the User Port. As an added protection measure, two electrostatic discharge protection devices are included to protect the pins of the user-port. The board already has sockets for these chips, so simply turn off the power and pop them in! No soldering required.
This upgrade includes the following:
1 x Western Design Center W65C22S6TPG-14: U28 – 65C22 User VIA IC
2 x Littelfuse SP720APP: TVS1 & TVS2 – ESD Protection Diode Packages
3 x Alliance AS6C4008: U4-U6 – 3 x 512KB SRAM ICs 1.5MB High RAM Upgrade