Sequential Systems Second Sight SVGS Graphics Card

Hardware entity

An expansion card for Apple ][ and IIgs that provides VGA output at up to 1024x768x256 (24-bit palette)

Rather than use the IIgs' new expansion slots, it used the old style slots (which the IIgs also had, slot 3 for early models or slots 1-6 for later models). This meant it would interface with the normal Apple II series. The card could also be configured to use a IIgs RGB monitor. Pointless on IIgs but useful for the Apple II series.

It has a Z180 on the chip and either 512KB or 1MB of RAM. No programming restrictions are imposed so the card is capable of producing anything a z180 and RAM could produce together. A sprite engine and/or software bitter for example. The Z180 is designed with multitasking and co-processing features and could be used as such. The second sight could also serve to provide additional memory to an Apple II. The 512KB model was marketed for the Apple II series while the 1MB model was intended for the IIgs. This under utilizes it's potential as a memory expansion for the Apple II series as the Z180 can function as a memory manager and allow even the original Apple II to add up to 1MB of memory despite it's 64K limit. That's an 800x600x256 game with 512K of additional memory to play with. Later Apple II models can use up to 1MB with an expansion card for a grand total of 2MB (16-bit Windows originally had an upper limit of 2 MB). An application written to use Second Sight RAM via the Z180 could address the full 1MB at once instead of using 16K banking (because the Z180 can see 1 MB at once).

Color modes 8-bit, 15-bit, 24-bit, 24-bit palette for all modes.
Graphics modes
640x480 (VGA cable only)
800x600x32768 (VGA cable only)
1024x768x256 (VGA cable only)
1024x400 (RGB cable only)
Text modes
While these modes are default, the card is capable of any resolution a developer wants to write a driver for. Interestingly, second site is compatible with sprite and video overlay cards..


Apple IIGS 1

Popular tags

cdrom mame rpgmaker