diff --git a/README.md b/README.md
index 0f50c3d..6831a67 100644
--- a/README.md
+++ b/README.md
@@ -79,6 +79,9 @@ required.  The options are:
 -c                            clears core including bootstrap ROM, if write enabled
 ```
 ```
+-cf <filename>                sets the name of the core file to read and write (default 'pymlac.core')
+```
+```
 -d <value>                    sets the console data switches to the <value>
 ```
 ```
@@ -98,9 +101,9 @@ required.  The options are:
 ```
 ```
 -t (<addr1> [,<addr2>] | off) controls the execution trace:
-                                  -t 0100    trace from address 0100 (octal)
-                                  -t 010,200 trace from 0100 octal to 200 decimal
-                                  -t off     turns trace off
+                                  -t 0100     trace from address 0100 (octal)
+                                  -t 0100,200 trace from 0100 octal to 200 decimal
+                                  -t off      turns trace off
 ```
 ```
 -ttyin <file>                 loads a file on to the teletype reader device