Tandy 1000 MS-DOS Reference Manual page 297

Chapter 13/ The DEBUG Utility
HEX
\
'
,
'
I '
i
I ,
,--;
[ I
H valuel value2
Performs hexadecimal arithmetic on valuel and value2.
Parameters
valuel value2
DEBUG first adds valuel and value2 and then subtracts value2
from valuel. The sum and difference are displayed on one line.
Example
H 19F 1 QJ A
I
ENTER
I
causes DEBUG to perform the arithmetic and displays the
results:
QJ2A9 QJQJ95
The sum of 19F and lOA is 02A9, and the difference is 0095.
INPUT
,...,
I I portaddress
..--l
Inputs and displays one byte from the specified port.
i :
Parameters
l_ ;
porta<jdress
is a 16-bit port address in hexadecimal.
Example
,
I \
I 2F8
I
ENTER
I
causes DEBUG to input the byte at Port 2F8 and display it. If
the byte is 42, DEBUG displays:
42
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