diff --git a/assembler-8608.lua b/assembler-8608.lua
index df23701..2c384d4 100644
--- a/assembler-8608.lua
+++ b/assembler-8608.lua
@@ -34,14 +34,17 @@ local function mnemFromLine(line, instrs, validWords)
 	local function addNum(n)
 		n = trim(n)
 		local val, len = decodeNumber(n)
+		local linei8  = line:gsub(n, "imm8", 1, true)
+		local linei16 = line:gsub(n, "imm16", 1, true)
+		if len==1 and (not instrs[linei8]) and instrs[linei16] then len = 2 end
 		table.insert(imms, { val = val, len = len } )
 		return " imm"..(len*8).." "
 	end
 	local function addLabel(n)
-		local len = 2
-		local linei8 = line:gsub(trim(n), "imm8", 1, true)
-		if instrs[linei8] then len = 1 end
 		n = trim(n)
+		local len = 2
+		local linei8 = line:gsub(n, "imm8", 1, true)
+		if instrs[linei8] then len = 1 end
 		table.insert(imms, { label = n, len = len } )
 		return " imm"..(len*8).." "
 	end
@@ -424,7 +427,10 @@ local function printMemory(mem)
 		local nonempty = false
 		for addr = base, base+15 do
 			if addr%4==0 then table.insert(line, " ") end
-			if mem[addr] then
+			if mem[addr]==false then
+				nonempty = true
+				table.insert(line, "XX ")
+			elseif mem[addr] then
 				nonempty = true
 				table.insert(line, string.format("%02X", mem[addr]).." ")
 			else