diff --git a/README.md b/README.md
index d16f476..12c7afd 100644
--- a/README.md
+++ b/README.md
@@ -29,9 +29,9 @@ Arguments are passed in reverse order with the stack so:
 lowest address = 1st stack arg
 highest address = last stack arg
 
-Should a function return more values than fit into the 7 registers, the caller has to allocate space on the stack for them, and pass the pointer to that space in r7.
-This reduces the amount of argument registers to 6 and all arguments above that shall go on the stack, the pointer to the result stack shall **always** be passed in r7.
-r7 points at the highest available address for results, with the 8th result being stored there, the 9th below it and so on.
+Should a function return more values than fit into the 7 registers, the caller has to allocate space on the stack for them, and pass the pointer to that space in the next free argument register.
+This reduces the amount of argument registers to 6 and all arguments above that shall go on the stack, the pointer to the result stack shall **always** be passed in an argument register.
+This register points at the highest available address for results, with the 8th result being stored there, the 9th below it and so on.
 
 ### Stack
 Grows downwards from top of memory.