From ec785f3a8a287ddc20d689e64d551aadfdeaf1c3 Mon Sep 17 00:00:00 2001
From: Thomas Harte <thomas.harte@gmail.com>
Date: Sat, 30 Mar 2024 20:54:17 -0400
Subject: [PATCH] Add URL as comment.

---
 Machines/Acorn/Archimedes/Archimedes.cpp | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/Machines/Acorn/Archimedes/Archimedes.cpp b/Machines/Acorn/Archimedes/Archimedes.cpp
index b2a2ef1c9..fb403d082 100644
--- a/Machines/Acorn/Archimedes/Archimedes.cpp
+++ b/Machines/Acorn/Archimedes/Archimedes.cpp
@@ -231,6 +231,8 @@ class ConcreteMachine:
 					for(int c = 0; c < 10; c++) swis.back().regs[c] = executor_.registers()[uint32_t(c)];
 
 					// Possibly capture more detail.
+					//
+					// Cf. http://productsdb.riscos.com/support/developers/prm_index/numswilist.html
 					uint32_t pointer = 0;
 					switch(instruction & 0xfd'ffff) {
 						case 0x41501: