diff --git a/asminc/cpu.mac b/asminc/cpu.mac
index 1f5c0758e..818d70df1 100644
--- a/asminc/cpu.mac
+++ b/asminc/cpu.mac
@@ -20,6 +20,8 @@ CPU_65SC02         = CPU_ISET_6502|CPU_ISET_65SC02
 CPU_65C02          = CPU_ISET_6502|CPU_ISET_65SC02|CPU_ISET_65C02
 CPU_65816          = CPU_ISET_6502|CPU_ISET_65SC02|CPU_ISET_65816
 CPU_SWEET16        = CPU_ISET_SWEET16
+; NOTE: HUC6280 removes "wai" ($cb) and "stp" ($db) from the 65C02 instruction set
 CPU_HUC6280        = CPU_ISET_6502|CPU_ISET_65SC02|CPU_ISET_65C02|CPU_ISET_HUC6280
+; NOTE: 45100 replaces "wai" ($cb) and "stp" ($db) of the 65C02 instruction set
 CPU_4510           = CPU_ISET_6502|CPU_ISET_65SC02|CPU_ISET_65C02|CPU_ISET_4510
 CPU_M740           = CPU_ISET_6502|CPU_ISET_M740
diff --git a/doc/ca65.sgml b/doc/ca65.sgml
index 095dcb7f3..22f9a03cf 100644
--- a/doc/ca65.sgml
+++ b/doc/ca65.sgml
@@ -4807,6 +4807,7 @@ each supported CPU a constant similar to
     CPU_HUC6280
     CPU_4510
     CPU_6502DTV
+    CPU_M740
 </verb></tscreen>
 
 is defined. These constants may be used to determine the exact type of the
@@ -4822,6 +4823,7 @@ another constant is defined:
     CPU_ISET_HUC6280
     CPU_ISET_4510
     CPU_ISET_6502DTV
+    CPU_ISET_M740
 </verb></tscreen>
 
 The value read from the <tt/<ref id=".CPU" name=".CPU">/ pseudo variable may