changed memory layout, ram needs to be where the stack will be

notes/memory-layout.md

@@ -4,28 +4,30 @@
 
 | start  | end    | use                     |
 | :----- | :----- | :---------------------- |
-| 0x8000 | 0x8000 | bank switching register |
-| 0x8001 | 0xDFFF | RAM                     |
+| 0x0000 | 0x5FFE | RAM                     |
+| 0x5FFF | 0x5FFF | bank switching register |
+| 0x6000 | 0xDFFF | --- to be mapped ---    |
 | 0xE000 | 0xFFFF | ROM                     |
 
 # Default (0X00)
 | start  | end    | use |
 | :----- | :----- | :-- |
-| 0x0000 | 0x7FFF | I/O |
+| 0x6000 | 0xDFFF | I/O |
 
 # [Persistent Memory](./persistent-memory.md) (0x01)
 | start  | end    | use     |
 | :----- | :----- | :------ |
-| 0x0000 | 0x7FFF | storage |
+| 0x6000 | 0xDFFF | storage |
 
 # [Monochrome Video](./monochrome-video.md) (0x0E, 0x0F)
-| start  | end    | use              |
-| :----- | :----- | :--------------- |
-| 0x0000 | 0x4AFF | VRAM             |
-| 0x6000 | 0x7FFF | character memory |
+| start  | end    | use               |
+| :----- | :----- | :---------------- |
+| 0x6000 | 0xAAFF | VRAM              |
+| 0xC000 | 0xDFFF | auxilliary memory |
 
 # [Color Video](./color-video.md) (0x10-0x19)
-| start  | end    | use  | bank      |
-| :----- | :----- | :--- | :-------- |
-| 0x0000 | 0x7FFF | VRAM | 0x10-0x18 |
-| 0x0000 | 0x3FFF | VRAM | 0x19      |
+| start  | end    | use               | bank      |
+| :----- | :----- | :---------------- | :-------- |
+| 0x6000 | 0xDFFF | VRAM              | 0x10-0x18 |
+| 0x6000 | 0x9FFF | VRAM              | 0x19      |
+| 0xA000 | 0xDFFF | auxilliary memory | 0x19      |

notes/monochrome-video.md

@@ -8,6 +8,7 @@
 - split in half
 - each half into page (0x0000 - 0x4AFF)
 - map character memory into top (0x6000 - 0x7FFF)
+- offset of 0x6000 into memory bus -> (0x6000 - 0xAAFF), (0xC000 - 0xDFFF)
 
 ## Design
 - derive CS from bank register, leave LSB free -> wire to MSB of VRAM address