Difference between revisions of "Category:84PCE:RAM:By Address"

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SafeRAM Areas:
 
SafeRAM Areas:
* D031F6 - pixelShadow
+
* D031F6: pixelShadow
* D052C6 - pixelShadow2
+
* D052C6: pixelShadow2
** These locations are rarely used by the OS, especially pixelShadow2. Each is 8400 bytes in length; and since they are linear, provide a total free space of 16800 bytes of RAM.
+
** These locations are rarely used by the OS, especially pixelShadow2.  
 +
** Each is 8400 bytes in length; and since they are linear, provide a total free space of 16800 bytes of RAM.
 
[[Category:84PCE:RAM|RAM Areas by Address]]
 
[[Category:84PCE:RAM|RAM Areas by Address]]

Revision as of 03:24, 7 April 2015

See also list of RAM areas by name.

The eZ80 has a 24-bit linear address space. Layout:

  • 000000h: Start of flash. The first 128 K are locked boot sectors. The first 8 are divided into 8 K sectors, all of which are locked. Implies that there is no longer a certificate.
  • 000066h: Flash exception handler. Write-to-flash without permission triggers the non-maskable interrupt to fire.
  • 00007Eh: Hardware/Emu flag: This byte indicates whether the ROM is a hardware ROM or emulator.
  • 000080h: Start of boot code jump table.
  • D00000h: Start of RAM. 256 K.
  • D40000h: Start of VRAM. 320x240x2 bytes = 153600 bytes.

SafeRAM Areas:

  • D031F6: pixelShadow
  • D052C6: pixelShadow2
    • These locations are rarely used by the OS, especially pixelShadow2.
    • Each is 8400 bytes in length; and since they are linear, provide a total free space of 16800 bytes of RAM.