From 79fdec74ff93619f14d2ba1dd70f99b633316efd Mon Sep 17 00:00:00 2001
From: uvok
Date: Wed, 21 Jan 2026 20:30:42 +0100
Subject: Document SUB command

---
 eater_cpu/readme.txt | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

(limited to 'eater_cpu/readme.txt')

diff --git a/eater_cpu/readme.txt b/eater_cpu/readme.txt
index a003415..b75a00c 100644
--- a/eater_cpu/readme.txt
+++ b/eater_cpu/readme.txt
@@ -30,7 +30,8 @@ instruction set
 
 NOP ____________  0b_0000_xxxx            No-op
 LDA <memaddress>  0b_0001_<memaddress>    Load memory > A
-ADD <memaddress>  0b_0010_<memaddress>    "Add memory" + A -> A
+ADD <memaddress>  0b_0010_<memaddress>    "Add memory": mem>B, A + B -> A
+SUB <memaddress>  0b_0011_<memaddress>    "Sub memory": mem>B, A - B-> A
 OUT ____________  0b_1110_xxxx            Output A -> OUT
 HLT ____________  0b_1111_xxxx            Sets halt flag
 ---
-- 
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