Difference between revisions of "Category:84PCE:General Hardware Information"

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Known hardware facts:
 
Known hardware facts:
 
* eZ80 CPU
 
* eZ80 CPU
 +
** Physical clock speed believed to be 48 MHz
 
** Effective clock speed between 12-15 MHz
 
** Effective clock speed between 12-15 MHz
 
** CPU might be clocked faster but have a lot of wait states
 
** CPU might be clocked faster but have a lot of wait states
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* User programs are '''prohibited''' from using '''any''' IN/OUT instructions
 
* User programs are '''prohibited''' from using '''any''' IN/OUT instructions
 
** OUT causes a reset
 
** OUT causes a reset
−
** IN is censored, because all Americans love censorship!
+
** IN produces a constant value
−
* But, there is ALSO still a flash unlock sequence
+
** The port protections make the following operations inaccessible: working with interupts, crystal timers, changing LCD parameters, and direct key input.
−
** Any attempts to circumvent these restrictions are likely to be blocked aggressively by TI like they do with the Nspire series
+
−
** No, you are not allowed to read directly from the keyboard port instead of using BCALLs
+
−
** No, you cannot change interrupt settings
+
−
** It doesn't matter if there are crystal timers, because you can't use them
+
−
** No, you are not allowed to use 8-bit palette mode
+
−
** No, you are not allowed to change the LCD base address to get double buffering
+
−
** You can set IM2, but you can't do anything useful with it (for very long) because you can't acknowledge interrupts
+
 
* Flash starts at $000000
 
* Flash starts at $000000
 +
** There is ALSO still a flash unlock sequence
 
* RAM starts at $D00000
 
* RAM starts at $D00000
−
** Why not $800000? No, seriously, why?
+
* Assembly programs and TI-BASIC programs are limited to one sector (64KB)
−
* No more assembly program size limit or execution limit
+
 
* VRAM starts at $D40000
 
* VRAM starts at $D40000
−
* VRAM is executable, for what it's worth
+
** VRAM is executable

Revision as of 12:05, 27 March 2015

The TI-84 Plus CE and TI-83 Premium are two models new in 2015. The former is for the USA region (maybe all of North American?) and the latter is for France. The hardware is virtually identical between the two models.

Known hardware facts:

  • eZ80 CPU
    • Physical clock speed believed to be 48 MHz
    • Effective clock speed between 12-15 MHz
    • CPU might be clocked faster but have a lot of wait states
  • 4 MB flash chip
    • Bottom-boot organization this time
  • 256 K main RAM
  • Memory-mapped LCD
    • 153600 bytes of VRAM confirmed, unknown if more exists
    • Possibly an ARM Primecell PL111
  • French version has testing LED; American version may get a testing LED in the future
  • User programs are prohibited from using any IN/OUT instructions
    • OUT causes a reset
    • IN produces a constant value
    • The port protections make the following operations inaccessible: working with interupts, crystal timers, changing LCD parameters, and direct key input.
  • Flash starts at $000000
    • There is ALSO still a flash unlock sequence
  • RAM starts at $D00000
  • Assembly programs and TI-BASIC programs are limited to one sector (64KB)
  • VRAM starts at $D40000
    • VRAM is executable

Pages in category "84PCE:General Hardware Information"

The following 3 pages are in this category, out of 3 total.

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