Changes between Version 7 and Version 8 of geniuspc

Timestamp:

May 13, 2012, 9:27:19 PM (12 years ago)

Author:

pulkomandy

Comment:

--

geniuspc

@@ -6 +6 @@
  * 1 to 4M of ROM (not sure yet) - Sharp LH537NWN mask ROM
  * Mass storage : 128KB flash memory - AM29F010
- * Cartridge port, apparently on memory bus with system ROM and storage flash. The french system comes with cartridges only containing straps, likely shorting some pins enable extra features... The german version seems to have extra flash memory or maybe ROM ?
+ * Cartridge port, apparently on memory bus with system ROM and storage flash. The french system comes with cartridges only containing straps, likely shorting some pins enable extra features...
 
-The ROM seems to be a 16-bit one, available directly on the CPU bus. The FLASH is 8-bit, but directly on the CPU bus  as well. The RAM is accessed through the VTech 27-05793 chip, which likely handles memory refresh.
-I don't know if the RAM is mapped as 16 or 8-bit to the CPU.
+The ROM seems to be a 16-bit one, available directly on the CPU bus. The FLASH is 8-bit, but directly on the CPU bus  as well. The cartridge port is connected to the same bus, and can be used for extra flash storage.
+
+Both flash chips (internal and cartridge) are 8-bit only. This means they can't be used for executable code.
+
+The RAM is accessed through the VTech 27-05793 chip, which likely handles memory refresh.
+I don't know if the RAM is mapped as 16 or 8-bit to the CPU, and if there are any wait states when accessing it or whatever. The VTech chip might also have some internal memory ?
 
 == Other chips ==
@@ -36 +40 @@
  * Mauve
  * Pink
+(the 16th color is likely "darker-than-black", used for blanking)
 
-Resolution seems to be something like 480x200
+Resolution seems to be something like 480x200. This makes a 48K framebuffer. Top and bottom borders can have different colors.
 
 The Genius PC is a home computer from VTech. Released in the late 90s, it is one of the last microcomputers.