22 
2.2.3  Special Function Keys 
The 
ten  blue keys in 
the 
upper 
left 
of 
the keyboard, marked 
Fl 
through 
FlO, 
are  called special 
function keys.  See Figure 2.16. 
[DDDDDDDDDDj 
TAPE  CONTROL 
FIGURE  2.16  Location 
of 
Special Function keys 
These keys are undefined when the MZ-80B 
is 
activated. The user can define a function for each 
of 
these keys 
by 
using 
the 
BASIC 
SB-5 
510 DEF KEY statement. 
To 
define 
the 
function 
of 
special function key I as the BASIC  command RUN, execute 
the 
follow-
ing statement: 
DEF KEY 
(1) 
=  RUN 
Once this statement 
is 
executed, special function key  1 performs 
the 
function 
of 
the RUN  com-
mand until it 
is 
redefined. Thus, when special function key I is pressed in 
the 
direct mode, the follow-
ing appears on 
the 
display. Then, 
by 
pressing 
CR 
]  key, 
the 
RUN command is executed. 
The 
[  c R  ]  key  can be  defined together with the RUN command 
as 
the function 
of 
a special 
function key, 
if 
desired. 
Execute 
DEF 
KEY 
(1) 
= 
RUN~ 
The  symbol  " r  "  represents  the  carriage 
return 
function, 
but 
there 
is 
no key 
on 
which this 
symbol  appears.  To  enter  this  symbol,  press  the 
[sn 
LOCK)  and  r-GRPH  )  keys  simultaneously.  When 
special  function key  1 
is 
defined in this manner, the command may be executed 
just 
by pressing 
the 
key once.