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

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(Fixed Hardware/Emu flag address)
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The eZ80 has a 24-bit linear address space. Layout:
 
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.
 
* 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.
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* 000066h: BrandonW handler. Write-to-flash without permission triggers the non-maskable BrandonW interrupt to fire.
+
* 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.
 
* 00007Eh: Hardware/Emu flag: This byte indicates whether the ROM is a hardware ROM or emulator.
 
* 000080h: Start of boot code jump table.
 
* 000080h: Start of boot code jump table.
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* D40000h: Start of VRAM. 320x240x2 bytes = 153600 bytes.
 
* D40000h: Start of VRAM. 320x240x2 bytes = 153600 bytes.
  
−
 
+
SafeRAM Areas:
 +
* D031F6h: pixelShadow
 +
* D052C6h: pixelShadow2
 +
* D07396h: cmdPixelShadow
 +
** Each is 8400 bytes in length; and since they are linear, provide a total free space of 25200 bytes of RAM.
 +
** pixelShadow2 is the most stable; and is a viable option for testing TSRs and hooks.
 
[[Category:84PCE:RAM|RAM Areas by Name]]
 
[[Category:84PCE:RAM|RAM Areas by Name]]

Revision as of 04:36, 7 April 2015

See also list of RAM areas by address.

Please read our page on Contributing before editing these pages!

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:

  • D031F6h: pixelShadow
  • D052C6h: pixelShadow2
  • D07396h: cmdPixelShadow
    • Each is 8400 bytes in length; and since they are linear, provide a total free space of 25200 bytes of RAM.
    • pixelShadow2 is the most stable; and is a viable option for testing TSRs and hooks.
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