diff --git a/src/apple2.text.c b/src/apple2.text.c
index 838ef06..4187a1a 100644
--- a/src/apple2.text.c
+++ b/src/apple2.text.c
@@ -225,12 +225,20 @@ static char alternate_display[] = {
     'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z', '{', '|', '}', '~', ' ', 
 };
 
+/*
+ * Return the primary character set representation matching the given
+ * character code.
+ */
 char
 apple2_text_primary(char ch)
 {
     return primary_display[ch];
 }
 
+/*
+ * Return the alternate character set representation matching the given
+ * character code.
+ */
 char
 apple2_text_alternate(char ch)
 {
diff --git a/src/vm_debug.c b/src/vm_debug.c
index e3a0cc4..911fbf6 100644
--- a/src/vm_debug.c
+++ b/src/vm_debug.c
@@ -422,6 +422,10 @@ DEBUG_CMD(step)
     vm_debug_break(cpu->PC);
 }
 
+/*
+ * Toggle disassembly, and print a notice of the change and its new
+ * status.
+ */
 DEBUG_CMD(disasm)
 {
     apple2 *mach = (apple2 *)vm_di_get(VM_MACHINE);
@@ -432,6 +436,13 @@ DEBUG_CMD(disasm)
     fprintf(stream, "disassembly %s\n", mach->disasm ? "ON" : "OFF");
 }
 
+/*
+ * Disassemble a block of memory from one given address to another.
+ * Useful when you want to see what memory looks like in a given region.
+ * Note that the disassembler is a bit dumb, and can't tell what data
+ * are opcodes is meant to be standalone binary data (the sort you would
+ * get if you used "DFB" notation in an assembler).
+ */
 DEBUG_CMD(dblock)
 {
     if (args->addr1 > args->addr2) {