Added English Language description for stbux instruction

diff --git a/openpower/isa/fixedstore.mdwn b/openpower/isa/fixedstore.mdwn
index ecdcd925be69ffc626e9b0d3c10d4f11bc76b9cb..e18f254199fb7e19dc47a0910524436e0913c82b 100644 (file)
--- a/openpower/isa/fixedstore.mdwn
+++ b/openpower/isa/fixedstore.mdwn
@@ -96,6 +96,16 @@ Pseudo-code:
     MEM(EA, 1) <- (RS)[XLEN-8:XLEN-1]
     RA <- EA
 
+Description:
+
+Let the effective address (EA) be the sum (RA)+ (RB).
+RS[56:63] are stored into the byte in storage addressed
+by EA.
+
+EA is placed into register RA.
+
+If RA=0, the instruction form is invalid.
+
 Special Registers Altered:
 
     None