Differential Monitor; Definition Of Signed Binary Data; Arithmetic Flags; Inputting Signed Binary Data Using Decimal Values - Omron CPM1 - PROGRAMING MANUAL 02-2001 Programming Manual

Differential Monitor

2-16-1 Definition of Signed Binary Data

2-16-2 Arithmetic Flags

2-16-3 Inputting Signed Binary Data Using Decimal Values

Inputting Instructions

2-17 Differential Monitor

Signed binary data is manipulated using 2's complements and bit 15 is used as
the sign bit. The range of data that can be expressed using one word is as fol-
lows:–32,768 to 32,767 (8000 to 7FFF hexadecimal).
The following table shows equivalents between decimal and hexadecimal data.
Decimal
32,767
32,766
.
.
.
2
1
0
–1
–2
.
.
.
–32,767
–32,768
The results of executing signed binary instructions is reflected in the arithmetic
flags. The flags and the conditions under which it will turn ON are given in the
following table. The flags will be OFF when these conditions are not met.
Flag
Carry Flag (SR 25504)
Equals Flag (SR 25506)
Although calculations for signed binary data use hexadecimal expressions, in-
puts from the Programming Console or SSS can be done using decimal inputs
and mnemonics for the instructions. The procedure to using the Programming
Console to input using decimal values is shown in the CPM1 Operation Manual,
CPM1A Operation Manual, CPM2A Operation Manual, CPM2C Operation
Manual, and SRM1 Master Control Unit Operation Manual. Refer to the SSS Op-
eration Manual: C-series PCs for details on using the SSS.
Refer to the CPM1 Operation Manual, CPM1A Operation Manual, CPM2C Op-
eration Manual, CPM2A Operation Manual, and SRM1 Master Control Unit Op-
eration Manual details on inputting instructions from the Programming Console.
The CPM1/CPM1A, CPM2A//CPM2C, and SRM1(-V2) support differential
monitoring from either the Programming Console or the SSS. The operator can
detect on OFF-to-ON or ON-to-OFF transition in a specified bit. When the speci-
fied transition takes place, the transition is indicated on the display and a buzzer
sounds to enable easy recognition of the transition.
Refer to the CPM1 Operation Manual, CPM1A Operation Manual, CPM2A Op-
eration Manual, CPM2C Operation Manual, or SRM1 Master Control Units Op-
eration Manual for details on the Programming Console Differential Monitor pro-
cedure and to the SSS Operation Manual: C-series PCs for the SYSMAC Sup-
port Software procedure.
4-digit Hexadecimal
7FFF
7FFE
.
.
.
0002
0001
0000
FFFF
FFFE
.
.
.
8001
8000
ON conditions
Carry in an addition.
Negative results for subtraction.
The results of addition, subtraction,
multiplication, or division is 0.
Results of converting 2's complement is 0.
Section 2-17
159