progress on serial and added editor

dsa_resources/idt.dsa

@@ -0,0 +1,61 @@
+include print: "./print.dsa"
+
+dw idt: 0xFFFF0000
+setup_base: func
+    push rg0
+    push rg1
+    push rg2
+    push rg3
+
+    ldw idt, idr // load the IDT into the IDR
+
+    // set all 256 interrupt addresses to point to guard
+    lwi _guard, rg1     // load address of guard handler
+    addi idr, 1024, rg2 // counter for 256 entries
+_loop_start:
+	stw rg1, rg2         // store guard into current IDT entry
+	subi rg2, 4, rg2     // decrement counter
+	ieq rg2, zero, rg3   // check if counter is zero
+	jnz rg3, _loop_start // repeat until all entries set
+
+    // make sure we can handle an invalid interrupt
+    lwi _handle_invalid_interrupt, rg0
+    stw rg0, idr, 0
+
+    pop rg3
+    pop rg2
+    pop rg1
+    pop rg0
+    return
+
+setup_io: func
+    push rg0
+
+    lwi _serial_interrupt, rg0
+    stw rg0, idr, 132 // 33*4, interrupt idx 32
+
+    pop rg0
+    return
+
+// does nothing, but wakes the kernel
+_serial_interrupt:
+    nop
+    iret
+
+db _invalid_int: "FATAL: Invalid Interrupt!"
+_handle_invalid_interrupt:
+	call print::reset
+	lwi _invalid_int, rg0
+	push rg0
+	call print::print
+	pop zero
+	hlt
+
+db _err: "FATAL: Interrupt handler was not set!"
+_guard:
+    call print::reset
+	lwi _err, rg0
+	push rg0
+	call print::print
+	pop zero
+	hlt