TRS-80 MODEL III
(BREAK)
Processing
The
(BREAK)
key is intercepted during keyboard scan operations. The Computer
transfers control to a three-byte
jump
vectorin
RAM
(hex values: C3 lsb msb). For
special applications, you maychange the
jump
vector addresses to allow your own
program to handle the
(BREAK)
key.
Thekeyscan
(BlJEAK)
jump
vectoris located at 16396 (X'
400C').
Register contentson entry to the
jump
vector
DE
= Modified by the Computer
(SP) = Thereturn address
of
the interrupted program. That is, a
RET
will transfer
control to the point at which the program was interrupted.
SampleBASIC Programming
Run this BASIC program to disable
rnBEAK).
10
POKE
16396,175
20
POKE
16397,201
'175
1-80
"XOR
A"
CODE
'201
=
Z-80
"RET"
CODE
Run this BASIC program to enable the
(BREAK)
key.
10
POKE
16396,201
12/22
'Z-80
"RET"
CODE
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