The V810 starts execution at address 0xFFFFFFF0H, meaning that when the Virtual Boy is switched on, it seeks instructions at that location. That being said, that address resides within the cartridge ROM, giving the game the upper hand in the initialisation of the hardware.
Also, there isn't any Basic Input/Output System (BIOS) chip on the motherboard, so no operating system or abstraction layer is present to simplify operations.
House chores
For this reason, Nintendo instructed developers to perform several chores to ensure the proper functioning of this console, including:
- WRAM becomes usable only after 200 microseconds (0.0002 seconds) following the console's startup. The documentation includes a list of steps that games must follow to account for this delay.
- Many years later, unofficial sources claimed that this was an erratum on Nintendo's part, and that it is the VIP's DRAM that actually requires waiting, as the datasheets corroborate .
- The game must populate the Column Table. To recall previous explanations, the 'active display' period is subject to a variable angular velocity. To prevent certain columns of the frame from appearing narrower than others, games fill a table in DRAM that applies corrections. To make things easier, Nintendo provided a default Column Table in their Software Development Kit (SDK), which games could use.
- The table can also be amended at any time during gameplay and, since it consequently controls the amount of LED emission, the table also serves as a mechanism for adjusting the amount of brightness per column.