ROM Header: Difference between revisions

(Updated the "clock rate" field description.)
 
(6 intermediate revisions by 3 users not shown)
Line 24:
|0x4
|Clock Rate
|Constant value used by libultra versions 2.0H0I and earlier, to naively calculate how much real-time has passed based on the CPU's Count register.
 
The value is masked by 0xFFFFFFF0, then multiplied by 0.75 to account for the CPU clock's multiplier (1.5x) and that the Count register increments every 2 CPU cycles.
Line 89:
Keep in mind that there is no known way for software to change the clock frequency used by either the RCP or CPU. So if/when games use the Count register divided by 46,875,000 to measure a real-time second, the calculated result will be inaccurate.
 
[[User:korgeauxPolprzewodnikowy|korgeauxPolprzewodnikowy]] from the N64brew Discord, experimented with Doom 64 and Star Fox 64 on real hardware. They found that increasing this value increases the delay before the copyright screen or Nintendo logo (respectively) shows up on screen.
|-
|0x08
|0x4
|Boot Address
|Initial PC in RDRAM. IPL3 will jumpDMA 1 MiB of ROM code from offset 0x1000 to this address when it has finished initializing the hardware, and then jump here to boot the ROM. The most common value for this field is 0x80000400.
 
 
Line 402:
|Ares
|Yes
|NoYes
|-
|cen64
Line 448:
|ed64
|None
|-
|UNFLoader
|Savetype supported
|-
| rowspan="3" |SummerCart64
|N64FlashcartMenu
|Savetype supported
|-
|sc64deployer
|Savetype supported
|-
|UNFLoader