Merge branch 'kdmmio-fix' into main

Fixes #22

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "fpgrars"
-version = "1.12.1"
+version = "1.13.0"
 authors = ["Leonardo Riether <leonardoalves8217@gmail.com>"]
 edition = "2018"
 

samples/keydown.s

@@ -0,0 +1,78 @@
+#############################################
+##                                         ##
+##  Colors the screen if a key is pressed  ##
+##  Uses KDMMIO_KEYDOWN, which isn't       ##
+##  compatible with RARS                   ##
+##                                         ##
+#############################################
+
+.macro exit
+    li a7 10
+    ecall
+.end_macro
+
+.data
+
+.text
+main:
+    li s0 0x0  # color
+    li s1 1    # frame
+    li s10 0   # last pressed key, only used for get_key
+
+main.loop:
+    mv a0 s0
+    mv a1 s1
+    jal print
+
+    jal is_key_down
+    mv s0 zero
+    beqz a0 not_red
+    li s0 0x7
+not_red:
+
+    xori s1 s1 1
+    j main.loop
+
+main.exit:
+    exit()
+
+# a0 = color
+# a1 = frame
+print:
+    slli a2 a1 20
+    li t0 0xff000000
+    or t0 t0 a2
+    li t1 76800
+    add t1 t1 t0
+
+    slli a2 a0 8
+    or a0 a0 a2
+    slli a2 a0 16
+    or a0 a0 a2
+
+print.loop:
+    bge t0 t1 print.exit
+
+#     li t2 -250
+# print.wait:
+#     bgez t2 print.wait.out
+#     addi t2 t2 1
+#     j print.wait
+# print.wait.out:
+
+    sw a0 0(t0)
+
+    addi t0 t0 4
+    j print.loop
+
+print.exit:
+    li a2 0xff200604
+    sb a1 0(a2)
+    ret
+
+is_key_down:
+	li t0 0xff210000
+	lb a0 0(t0)
+	lw t0 4(t0) # Clear KDMMIO_Data bit
+	ret
+

src/renderer/mod.rs

@@ -11,7 +11,20 @@ pub const HEIGHT: usize = 240;
 pub const FRAME_SELECT: usize = 0x20_0604;
 pub const FRAME_0: usize = 0;
 pub const FRAME_1: usize = 0x10_0000;
-const KEYBOARD: usize = 0x20_0000;
+
+/// Control bit for the Keyboard (Display?) MMIO.
+/// `mmio[KDMMIO_CONTROL] == 1` means that a new key has been put in `mmio[KDMMIO_DATA]`, like a
+/// keydown event. The control bit will be cleared right after you read a byte/half_word/word from
+/// `mmio[KDMMIO_DATA]`. `KDMMIO_KEYDOWN` is easier to use, but not supported by other simulators.
+pub const KDMMIO_CONTROL: usize = 0x20_0000;
+pub const KDMMIO_DATA: usize = 0x20_0004;
+
+/// `mmio[KDMMIO_KEYDOWN] == 1` means that some key is currently down/pressed. Not supported by
+/// other simulators, but switching from `0x21` to `0x20` should be easy enough.
+/// `mmio[KDMMIO_DATADOWN]` is a duplicate of `mmio[KDMMIO_DATA]`
+pub const KDMMIO_KEYDOWN: usize = 0x21_0000;
+pub const KDMMIO_DATADOWN: usize = 0x21_0004;
+
 const KEYBUFFER: usize = 0x20_0100;
 const KEYBUFFER_SIZE: usize = 8;
 const KEYMAP: usize = 0x20_0520;
@@ -56,8 +69,11 @@ impl InputState {
 
                 let mut mmio = state.mmio.lock().unwrap();
 
-                mmio[KEYBOARD] = 1;
-                mmio[KEYBOARD + 4] = chr as u8;
+                mmio[KDMMIO_CONTROL] = 1;
+                mmio[KDMMIO_DATA] = chr as u8;
+
+                mmio[KDMMIO_KEYDOWN] = 1;
+                mmio[KDMMIO_DATADOWN] = chr as u8;
 
                 true
             }
@@ -102,6 +118,8 @@ impl InputState {
             } => {
                 let mut mmio = state.mmio.lock().unwrap();
 
+                mmio[KDMMIO_KEYDOWN] = 0;
+
                 push_key_to_buffer(&mut mmio, 0xF0);
                 push_key_to_buffer(&mut mmio, *key as u8);
 

src/simulator/memory.rs

@@ -3,14 +3,12 @@ use std::io::Read;
 use std::sync::{Arc, Mutex};
 
 pub const DATA_SIZE: usize = 0x0040_0000; // TODO: this, but I think it's about this much
-pub const MMIO_SIZE: usize = 0x0021_0000;
+pub const MMIO_SIZE: usize = 0x0022_0000;
 pub const MMIO_START: usize = 0xff00_0000;
-pub const KBMMIO_CONTROL: usize = 0xff20_0000;
-pub const KBMMIO_DATA: usize = 0xff20_0004;
 
 pub const HEAP_START: usize = 0x1004_0000;
 
-use crate::renderer::{FRAME_0, FRAME_1, HEIGHT, WIDTH};
+use crate::renderer::{FRAME_0, FRAME_1, HEIGHT, WIDTH, KDMMIO_CONTROL, KDMMIO_DATA};
 pub const VIDEO_START: usize = MMIO_START + FRAME_0;
 pub const VIDEO_END: usize = MMIO_START + FRAME_1 + WIDTH * HEIGHT;
 
@@ -74,8 +72,8 @@ impl Memory {
         if i >= MMIO_START {
             // MMIO
             let mut mmio = self.mmio.lock().unwrap();
-            if i == KBMMIO_DATA {
-                mmio[KBMMIO_CONTROL - MMIO_START] = 0;
+            if i == KDMMIO_DATA + MMIO_START {
+                mmio[KDMMIO_CONTROL] = 0;
             }
             read(&mmio[i - MMIO_START..])
         } else if i >= HEAP_START {