© MCS Electronics, 1995-2007
ABS
Action
Returns the absolute value of a numeric signed variable.
Syntax
var = ABS(var2)
Remarks
Var |
Variable that is assigned with the absolute value of var2. |
Var2 |
The source variable to retrieve the absolute value from. |
|
|
var : Integer , Long, Single or Double. var2 : Integer, Long, Single or Double.
The absolute value of a number is always positive.
See also
NONE
ASM
Calls: _abs16 for an Integer and _abs32 for a Long
Input: R16-R17 for an Integer and R16-R19 for a Long
Output:R16-R17 for an Integer and R16-R19 for a Long
Calls _Fltabsmem for a single from the fp_trig library.
Example
Dim a as Integer, c as Integer a =-1000
c = Abs(a) Print c End
ACOS
Action
Returns the arccosine of a single in radians.
Syntax
var = ACOS( x )
page -270-
|
© MCS Electronics, 1995-2007 |
|
Remarks |
||
Var |
A floating point variable such as single or double, that is assigned with |
|
|
the ACOS of variable x. |
|
X |
The float to get the ACOS of. Input is valid from –1 to +1 and returns |
|
|
p to 0. |
|
|
If Input is < -1 than p and input is > 1 than 0 will returned. |
|
|
|
|
If Input is cause of rounding effect in float-operations a little bit over 1 or -1, the value for 1.0 (-1.0) will be returned. This is the reason to give the value of the limit-point back, if Input is beyond limit. Generally the user have to take care, that Input to this function lies within –1 to +1.
All trig functions work with radians. Use deg2rad and rad2deg to convert between radians and angles.
See Also
RAD2DEG , DEG2RAD , COS , SIN , TAN , ATN , ASIN , ATN2
Example
$regfile = "m48def.dat" |
' specify the used |
micro |
' used crystal |
$crystal = 8000000 |
|
frequency |
' use baud rate |
$baud = 19200 |
|
$hwstack = 32 |
' default use 32 |
for the hardware stack |
' default use 10 |
$swstack = 10 |
|
for the SW stack |
' default use 40 |
$framesize = 40 |
|
for the frame space |
|
Config Com1 = Dummy , Synchrone = 0 , Parity = None , Stopbits = 1 , Databits = 8 , Clockpol = 0
Dim S As Single , X As Single
x= 0.5 : S = Acos(x)
Print S
End
ALIAS
Action
Indicates that the variable can be referenced with another name.
Syntax
newvar ALIAS oldvar
Remarks
oldvar 
Name of the variable such as PORTB.1
page -271-
© MCS Electronics, 1995-2007
newvar 
New name of the variable such as direction
Aliasing port pins can give the pin names a more meaningful name. For example, when your program uses 4 different pins to control 4 different relays, you could name them portb.1, portb.2, portb.3 and portb.4.
But it would be more convenient to refer to them as relais1, relais2, relais3 and realais4.
When you later on change your PCB and decide that relays 4 must be connected to portD.4 instead of portb.4, you only need to change the ALIAS line, and not your whole program.
See also
CONST
Example
'----------------------------------------------------------------------------- |
|
-- |
: (c) 1995-2005, MCS Electronics |
'copyright |
|
'micro |
: Mega48 |
'suited for demo |
: yes |
'commercial addon needed |
: no |
'purpose |
: demonstrates ALIAS |
'----------------------------------------------------------------------------- |
|
-- |
|
$regfile = "m48def.dat" |
' 4 MHz crystal |
$crystal = 4000000 |
|
Const On = 1 |
|
Const Off = 0 |
|
Config Portb = Output |
|
Relais1 Alias Portb.1 |
|
Relais2 Alias Portb.2 |
|
Relais3 Alias Portd.5 |
|
Relais4 Alias Portd.2 |
|
Set Relais1 |
|
Relais2 = 0 |
|
Relais3 = On |
|
Relais4 = Off |
|
End |
|
ASC
Action
Assigns a numeric variable with the ASCII value of the first character of a string.
Syntax
var = ASC(string)
Remarks
Var 
Target numeric variable that is assigned.
page -272-
© MCS Electronics, 1995-2007
String 
String variable or constant from which to retrieve the ASCII value.
Note that only the first character of the string will be used.
When the string is empty, a zero will be returned.
ASCII stands for American Standard Code for Information Interchange. Computers can only understand numbers, so an ASCII code is the numerical representation of a character such as 'a' or '@' or an action of some sort. ASCII was developed a long time ago and now the non-printing characters are rarely used for their original purpose. Below is the ASCII character table and this includes descriptions of the first 32 non-printing characters. ASCII was actually designed for use with teletypes and so the descriptions are somewhat obscure. If someone says they want your CV however in ASCII format, all this means is they want 'plain' text with no formatting such as tabs, bold or underscoring - the raw format that any computer can understand. This is usually so they can easily import the file into their own applications without issues. Notepad.exe creates ASCII text, or in MS Word you can save a file as 'text only'
Extended ASCII
As people gradually required computers to understand additional characters and non-printing characters the ASCII set became restrictive. As with most technology, it took a while to get
page -273-
© MCS Electronics, 1995-2007
a single standard for these extra characters and hence there are few varying 'extended' sets. The most popular is presented below.
See also
CHR
ASM
NONE
Example
$regfile = "m48def.dat" |
' specify the used |
micro |
' used crystal |
$crystal = 8000000 |
|
frequency |
' use baud rate |
$baud = 19200 |
|
$hwstack = 32 |
' default use 32 |
for the hardware stack |
|
page -274-