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## Boot ROM
Execution starts here, at address `$0000`.
The OS bootloader is located here.
Execution starts here, at address `$0000`.<br>
The main program is located here, or the OS bootloader if an OS is present.
## GPIO
Contains hardware multiplication (`$0400`-`$0401`) and division (`$0402`-`$0403`), popcount (`$0404`), and a timer (`$0405`).
Contains hardware multiplication (`$0400 * $0401 -> $0400`) and division (`$0402 / $0403 -> $0402 r $0403`), popcount (`$0404 -> $0404`), and a timer (`$0405`).<br>
Value written to timer register = number of game ticks (32 ms) between interrupt triggers.<br>
Write 0 to disable.
## Keyboard
Read address `$0500` to get the next key event (7-bit Windows VKey code, MSB on indicates press/release). Returns 0 if empty.
Write 1 to `$0500` to enable interrupts.
Read address `$0500` to get the next key event<br>
7-bit Windows VKey code, MSB 1 = press, 0 = release<br>
Returns 0 if buffer is empty.
Write 1 to `$0500` to enable keyboard interrupts, 0 to disable.
## Serial Peripheral Interface
Not yet implemented.
## Robot Controller
Not directly mentioned in the provided code snippets, but if it follows a similar addressing scheme, it would have a specific range not covered here.
Write to `$0701` to control the robot. Each bit is an action - MSB to LSB: Plant brick, destroy brick, move forward, backward, left, right, up, down.<br>
Write a 6-bit color ID to `$0700` to set the color of the bricks the robot plants.<br>
Read `$0700` to get the color of the brick the robot is on. MSB = brick exists. Returns 0 if no brick.
## Text Display
Write ASCII values to addresses `$0800` to `$0FFF` to display characters at certain positions on the screen.
`$0800` is the top left, `$0FFF` would be the bottom right, considering the character display dimensions and memory layout.
Write ASCII values to `$0800` to `$0BFF` to display characters at certain positions on screen.<br>
`$0800` is top left, `$0BFF` is bottom right, rows are 64 bytes.
## Text Display Color
Write 6-bit color IDs to addresses `$0800` to `$0FFF` to set the color of characters on screen.
MSB = whether to invert character mask (i.e., for highlighting). This might need clarification or correction based on the actual implementation, as it seems to overlap with the Text Display's address range.
Write 6-bit color IDs to `$0C00` to `$0FFF` to set the color of characters on screen.<br>
MSB = whether to invert character mask (i.e. for highlighting).
## System RAM
The OS may use this memory for the stack, system variables, etc., located at `$1000` to `$1FFF`.
The OS may use this memory for the stack, system variables, etc.<br>
If no OS is present, this memory can be used for any purpose, etc.<br>
Located at `$1000` to `$1FFF`.
## User ROM
Your program and data go here, located at `$2000` to `$2FFF`.
User program and data can go here.<br>
If no OS is present, the boot ROM will need to jump into this code.<br>
Located at `$2000` to `$2FFF`.
## User RAM
Your code can use this memory for variables, arrays, a heap, etc., located at `$3000` to `$3FFF`.
## Video Display
Not directly mentioned in the provided snippets for addressing, but based on the peripheral configuration, it would be addressed from `$8000` to `$FFFF` for direct pixel manipulation or other video-related functions.
Your code can use this memory for variables, arrays, a heap, etc.<br>
Located at `$3000` to `$3FFF`.