Chap5-2 The Command Set: ABS

Omikron BASIC for Apple Power Mac

5-1. & to @ | Contents | 5-3. CINTL - DEFAULT

Chapter 5-2

The Command Set

ABS - CINT

ABS

Type: Function

Syntax: ABS(<num.expression>)

Explanation: ABS computes the absolute value of the numerical expression. Negative values thus receive a positive sign while positive values remain unchanged.

Example:

A=-5.2
PRINT A
PRINT ABS(A)
PRINT ABS(A+3.2)+3.2

Result:

-5.2
5.2
5.2

AES

Explanation: Has no application purpose in Omikron Basic 6 and is ignored by the compiler. Please, do not use.

AND

Type: Operator

Syntax: <num.expression>AND<num.expression>

Explanation: The expressions are linked with the logical Boolean operator AND, which takes two values, resolving to a single value.

Example:

PRINT BIN$(%1010 AND %1100)
IF 1<2 AND 2<3 THEN PRINT "I knew it!"
IF 1<4 AND 2=4 THEN PRINT "That's wrong!!!"

Result:

1000
I knew it!

See also OR NOR NAND XOR IMP EQV

ARCCOS

Type: Function

Syntax: ARCCOS(<num.expression>)

Explanation: Calculates the arcus cosine of the numerical expression. The numerical expression must have a value between -1 and 1. The result is dependent on the adjusted angle mode.

Example:

PRINT ARCCOS(-0.5)
DEG
PRINT ARCCOS(1)

Result:

2.0943951023932
0

See also: DEG RAD

ARCCOT

Type: Function

Syntax: ARCCOT(<num.expression>)

Explanation: Calculates the arcus cotangent of the numerical expression. The result is dependent on the adjusted angle mode (see DEG, RAD).

Example:

PRINT ARCCOT(5)
DEG
PRINT ARCCOT(1)

Result:

0.197395559849881
45

See also: DEG RAD

ARCOTH

Type: Function

Syntax: ARCOTH(<num.expression>)

Explanation: Calculates the area (inverse) hyperbolic cotangent of the numerical expression. The numerical value must be outside of the number interval -1 to 1.

Example:

PRINT ARCOTH(5)

Result:

0.202732554054082

ARCSIN

Type: Function

Syntax: ARCSIN(<num.expression>)

Explanation: Calculates the arcus sine of the numerical expression. The numerical expression must have a value between -1 and 1. The result is dependent on the adjusted angle mode. (See also, DEG, RAD)

Example:

PRINT ARCSIN(1)
DEG
PRINT ARCSIN(0.5)

Result:

1.5707963267949
30

ARCTAN

Type: Function

Syntax: ARCTAN(<num.expression>)

Explanation: Calculates the arcus tangent of the numerical expression. ARCTAN is identical to ATN. The result is dependent on the adjusted angle mode.

Example:

PRINT ARCTAN(-1)
DEG
PRINT ARCTAN(1)

Result:

-0.785398163397448
45

ARSINH

Type: Function

Syntax: ARSINH(<num.expression>)

Explanation: Calculates the area (inverse) hyperbolic sine of the numerical expression.

Example:

PRINT ARSINH(-1)

Result:

-0.881373587019543

ARTANH

Type: Function

Syntax: ARTANH(<num.expression>)

Explanation: Calculates the area (inverse) hyperbolic tangents of the numerical expression. The numerical expression must have a value between -1 and 1.

Example:

PRINT ARTANH(0.5)

Result:

0.549306144334055

AS

Explanation: see NAME...AS

ASC

Type: Function

Syntax: ASC(<string expression>)

Explanation: Determines the ASCII value of the first character of the string expression. ASC is the reverse function of CHR$. For more information, turn to the ASCII table in the appendix.

Caution: If A$ is an empty string, the call ASC(A$) returns zero if the nonfatal error messages have been turned off (Error_messages 0) and leads to the message "Illegal function call" if not.

Example:

PRINT ASC("abc")
PRINT ASC( CHR$(24))

Result:

97
24

See also CHR$

ATN

Type: Function

Syntax: ATN(<num.expression>)

Explanation: Calculates the arcus tangent of the numerical expression. ATN is identical to ARCTAN. The result is dependent on the adjusted angle mode (see DEG, RAD).

Example:

PRINT ATN(-1)
DEG
PRINT ATN(1)

Result:

-0.785398163397448
45

BACKUP

Type: Command

Syntax: BACKUP(<string expression>)
BACKUP(<file name>)

Explanation: Creates a backup copy from a file. The backup copy receives the extension "BAK" and is posted in the same folder. The FileSpecificationRecord must contain such a <file name> as it is returned e.g., from FILESELECT or FN Get_Fsspec$ from the Extension Library.
Wildcard characters are not permitted in the file. If the file cannot be found, the command is cancelled. An error message is issued if Error_Messages is activated.

Example:

BACKUP Fn GetFsspec$(0,0,"OmikronBasic")

Result:

A file copy with the name OmikronBasic.BAK is generated from the file OmikronBasic.

See also COPY

BIN$

Type: Function

Syntax: BIN$(<num.expression>)

Explanation: The numerical expression is converted into a character string, which represents the rounded value of the expression as a binary number. First, the numerical expression is always converted to the long integer format. A value with a too large amount generates an "Integer overflow" error message, if the FPU Exceptions were previously activated with the compiler control word "FPUEXON."

Example:

PRINT BIN$(4)
PRINT BIN$(24)
PRINT BIN$(1E+10)

Result:

%100
%11000
Integer overflow in line no. 2

See also: OCT$ HEX$ STR$ VAL

BIOS

Explanation: Has no application purpose in Omikron Basic 6 and is ignored by the compiler. Please, do not use.

BIT

Type: Function

Syntax: BIT(<num.expression>,<num.expression>)
BIT(<bit number>,<value>)

Explanation: The rounded value is converted to a 32-digit binary number. If the amount of a value is too large, it will generate the error message "Integer overflow" if the FPU exceptions were turned on with the compiler control word "FPUEXON." The function returns -1, if the bit on the right of the binary number is set, otherwise, 0. The bit with the lowest value has the number 0. The bit with the highest value has the number 31 and represents the sign in case of signed numbers.
An erroneous bit number generates the error message "Illegal vunction call" if monitoring of the range control was previously activated using COMPILER "RCON."

Example:

PRINT BIT(0,1)
PRINT BIT(2,1)
PRINT BIT(31,-1)
PRINT BIT(12,-1)

Result:

-1
0
-1
-1

See also: BIT as a command

BIT

Type: Command

Syntax: BIT(<num.expression>,{<integer variable>|(<num.expression>)}) =<num.expression>
BIT(<bit number>,{<integer variable>|(<memory address>)})=<bit value>

Explanation: Assigns the value zero (0) to an individual bit, if the <bit value> equals zero, otherwise the value one (1). The bit is indicated by the <bit number>. The bit with the lowest value has the bit number zero. Bits can be changed either by integer variables or by the memory.

Important: If the memory has undergone any changes, any access will occur byte-wise, i.e., the highest bit number is 7. However, when modifying integer variables, bit numbers up to 31 are permitted.
An erroneous bit number generates the error message "Illegal function call" if range control monitoring was previously activated using COMPILER "RCON."

Example:

Address=MEMORY(1)
PRINT PEEK(Address)
BIT (2,(Address ))= 1
PRINT PEEK(Address)
A=19
BIT (2,A)=0
PRINT A

Result:

0
4
17

BITBLT

Type: Command

Syntax: BITBLT<num.expression>[,<num.expression>,<num.expression>,<num.expression>] TO <num.expression>[,<num.expression>,<num.expression>,<num.expression>] [;<num.expression>]
BITBLT <num.expression>TO <num.expression>,COLOR <num.expression>

1: BITBLT <X1>,<Y1>,<width>,<height> TO <X2>,<Y2>,<width2>, <height2>[;<mode>]
2: BITBLT <X>,<Y>,<width>,<height>TO <memory address>[;<mode>]
3: BITBLT <memory address>TO <X>,<Y>,<width>,<height>[;<mode>]
4: BITBLT <memory address1>TO <memory address2>,COLOR <color>

Explanation: Copies a rectangular screen section depending on syntax:

1: from screen to screen
2: from screen to memory
3: from memory to screen
4: from memory to memory

Source and target oblongs can differ in size. The source image is modified by the command in such a way as to fit it exactly into the target oblong. Therefore, the BITBLT command can also be used for the purpose of enlarging, reducing, or distorting images.
In the case of syntax 1 to 3, the specification of a mode is possible as well, which allows for a point by point linking of the image information between source and target:

MODE 0: Target = Source
MODE 1: Target = Source AND Target
MODE 2: Target = NOT (Source XOR Target)
MODE 3: Target = NOT Target OR Source
MODE 4: Target = NOT Source
MODE 5: Target = NOT Target AND Source
MODE 6: Target = Source XOR Target
MODE 7: Target = Source OR Target
MODE 32: Target = (Source + Target)\2
MODE 33: Target = MIN($FFFF, Source + Target)
MODE 34: Target = (Source + Target) MOD $FFFF
MODE 35: Target = MAX(0, Source - Target)
MODE 36: Target = Source, if source is not white (transparent mode)
MODE 37: Target = MAX(Source, Target)
MODE 38: Target = (Source - Target + $FFFF) MOD $FFFF
MODE 39: Target = MIN (Source, Target)

Each Source and Target represent a 6-byte RGB Record whereby R=Red, G=Green, and B=Blue can consist of values between 0 and $FFFF.
If the specification <mode> is omitted, the process is performed according to 'MODE 0'. Any bit block transfer send to the screen takes a defined graphics window into consideration (see CLIP).
In the syntax BITBLT Adr1 TO Adr2, COLOR P indicates P, how many color planes the target image should have. Therefore, this command can be used in order to modify the pixel depth of an image.

The memory requirements for a BITBLT to memory can be calculated as follows:

Memory requirement = 6+((width+15) * height * color planes) SHR 3

The leading three words consist of the following:
1. Number of color planes
2. Width in pixels
3. Height in pixels

Example:

Screen_Buffer= MEMORY(6+((60+15)*40*8) SHR 3):'with 256 colors
PELLIPSE 50,50,30,20
BITBLT 25,20,50,50 TO Screen_Buffer
WAIT .5
CLS
BITBLT Screen_Buffer TO 20,20,50,50
WAIT .5
BITBLT 20,20,50,50 TO 20,30,50,50,6
WAIT .5
PCIRCLE 45,55,8

Result:

First, a screen buffer is created using MEMORY. After this, an ellipse is drawn and transferred to the buffer using BITBLT. After the screen was cleared, the ellipse is now again loaded from the buffer and then once again copied to the screen. Finally, a circle is drawn.

See also: BLOAD BSAVE

BLOAD

Type: Command

Syntax: BLOAD <string expression>[,<num.expression>]
BLOAD <file name>[,<start address>]

Explanation: The indicated file is loaded into memory commencing at the start address. If this expression is missing, the output is directed to the screen (logical screen address) and to the uppermost Omikron Basic output window (if one is open), respectively. In this case, width, height, and pixel depth are adapted automatically. For this purpose, the file must be available in the PICT format such as it is e.g., automatically created by BSAVE. PICT files created with other programs can be loaded with BLOAD as well.

Caution: You have to take care, that enough memory is reserved at <start address> for receiving the whole file. Otherwise a crash would be propably the result.

Example:

Mem= MEMORY(100)
BLOAD FN Get_Fsspec$(0,0,"EXAMPLE.DAT"),Mem

Result:

Memory is first reserved. The file EXAMPLE.DAT is then loaded into memory.

See also: BSAVE BITBLT

BOX

Type: Command

Syntax: BOX <num.expression>,<num.expression>{TO <num.expression>,<num.expression>|,<num.expression>,<num.expression>}
BOX <X>,<Y>{TO <X2>,<Y2>|<width>,<height>}

Explanation: Draws an unfilled oblong on the screen. Hereby, either two opposite corners are to be indicated or a corner, width, and height of the oblong. Color, line style, and width can be determined using LINE COLOR, LINE STYLE, and LINE WIDTH respectively. A window defined by CLIP, is not drawn outside of this area.

Example:

BOX 20,30,70,40

Result:

Draws an oblong

See also: PBOX PRBOX RBOX

BRK

Type: Command

Syntax: BRK

Explanation: This command is used exclusively for the error location in compiled programs. It triggers a jump in the compiled product to the debugger. Of course, that is only possible if a debugger was started before, otherwise, the Mac crashes with the message "Unimplemented Trap." This command offers the opportunity to interrupt a program at a specific location so as to initiate the search for errors with a debugger on an object code level.

Example:

Result:

BSAVE

Type: Command

Syntax: BSAVE <string expression>[,<num.expression>,<num.expression>]
BSAVE <file name>[,<start address>,<length>]

Explanation: Saves the memory area starting at <start address> under the <file name>. If <start address> and <length> are missing, the screen and the uppermost Omikron Basic output window, respectively, are stored instead. In this case, the save procedure occurs in the PICT format, whereby it is possible to load the image to any graphics port with BLOAD or to process it further with another program.

Example:

BSAVE FN Get_Fsspec$(0,0,"Screen.PICT")

Result:

The contents of the screen buffer are transferred to the file Screen.PICT.

See also: BITBLT BLOAD

CALL

Type: Command

Syntax: CALL <num.variable>[(][L ]<num.expression>][[, [L ]<num.expression>]])]

Explanation: A machine language subroutine is called. The start address is supplied by the numerical variable. The following expressions are passed to the stack in reverse order, i.e., the first parameter is at the bottom of the stack, that is, at "0,R31". The expressions may be preceded by an "L" in order to pass the appropriate parameter as long integers. Otherwise, a short integer is always passed.
Only those registers declared by Apple as 'volatile' may be modified. They are as follows:
R0,R3-R12 FPR0-FPR13 CR0,CR1,CR5-CR7
R31 points to the dynamic stack on which the passed parameters are located. The program must end with 'Blr'. If the link register is modified, it is to be ensured that it is restored again before the return. At the completion of the machine program, the contents of R3 can be loaded with RESERVED(0).
Errors caused by the machine program cannot be intercepted by Omikron Basic. Therefore, starting a suitable debugger in the test phase first is recommended.

Example:

Test$= "PNJLSPO/TPGUXBSF"
CALL Decode (L &Test$, 1) 'Pass pointer to Test$ and "1"
PRINT Test$

The machine program: (Was created with the Assembler Library for Omikron Basic 6.)

Lwz R6,0,R31:'Load pointer to string
Lhz R4,4,R31:'Load parameter (the "1")
Lwz R7,0,R6:'Generate pointer to string segment
Lwz R3,4,R6:'Length of string
Subi R7,R7,1
Mtctr R3

Label "loop"
Lhz R5,1,R7:'Load a character of the string
Sub R5,R5,R4:' Modify character
Stbu R5,1,R7:'And return character
Bdnz_ "loop":For all characters of the string
Blr

Result:

Omikron.SOFTWARE

CASE

Type: Command

Syntax: CASE <expression>[TO <expression>][[,<expression> [TO <expression>]]]

Explanation: Within a SELECT ... CASE statement, CASE introduces a partial branch. This program branch is then carried out if one of the indicated possibilities applies to the variable mentioned in the case of SELECT. Several possibilities are simply listed separated by commas. Intervals are also possible using TO. In the case of strings, only the first 4 bytes are parsed.

Example:

Result:

See also SELECT DEFAULT OTHERWISE

CDBL

Type: Function

Syntax: CDBL(<num.expression>)

Explanation: Converts any numerical expression to a double precision floating point format.

Example:

A!=1
B!=3
PRINT CDBL(A!/B!)
PRINT CDBL(A!)/CDBL(B!)

Result:

0.333333333333333
0.333333333333333

See also: CINT CINTL CSNG

CHAIN

Explanation: Has no application purpose in Omikron Basic 6 and is ignored by the compiler. Please, do not use.

CHDIR

Type: Command

Syntax: CHDIR <string expression>

Explanation: Changes the default path to the path indicated in <string expression>. Such a FileSpecificationRecord must be passed to the command as is returned e.g., by FILESELECT or FN Get_Fsspec$ from the Extension Library.

Example:

CHDIR FN Get_Fsspec(0,0,"MacintoshHD:Omikron Basic:Programe:")

Result:

The specified path becomes the current path.

CHR$

Type: Function

Syntax: CHR$(<num.expression>)

Explanation: Generates a string one character in length in accordance with the ASCII table. CHR$ is the reverse function of ASC. For more information, see the ASCII table in the appendix.

Example:

PRINT CHR$(7):'Triggers the system beep
PRINT CHR$(80); CHR$(76)

Result:

PL (indicates a short sound is emitted.)

See also ASC

CINT

Type: Function

Syntax: CINT(<num.expression>)

Explanation: Converts any numerical value to the short integer format (integers of -32768 to +32767). Of course, the definition range of the function especially encompasses the range of short integer numbers. Other values lead to the error message "Integer overflow" if range control monitoring was previously activated using COMPILER "RCON."

Example:
A=1
B=3
PRINT CINT(A/B)
PRINT CINT(A)/CINT(B)
PRINT CINT(40000)

Result:
0
0.333333333333333
Integer overflow in line no. 4

CINTL CSNG CDBL

	ABS
Type:	Function
Syntax:	ABS(<num.expression>)
Explanation:	ABS computes the absolute value of the numerical expression. Negative values thus receive a positive sign while positive values remain unchanged.
Example:	A=-5.2 PRINT A PRINT ABS(A) PRINT ABS(A+3.2)+3.2
Result:	-5.2 5.2 5.2

	AES
Explanation:	Has no application purpose in Omikron Basic 6 and is ignored by the compiler. Please, do not use.

	AND
Type:	Operator
Syntax:	<num.expression>AND<num.expression>
Explanation:	The expressions are linked with the logical Boolean operator AND, which takes two values, resolving to a single value.
Example:	PRINT BIN$(%1010 AND %1100) IF 1<2 AND 2<3 THEN PRINT "I knew it!" IF 1<4 AND 2=4 THEN PRINT "That's wrong!!!"
Result:	1000 I knew it!
See also	OR NOR NAND XOR IMP EQV

	ARCCOS
Type:	Function
Syntax:	ARCCOS(<num.expression>)
Explanation:	Calculates the arcus cosine of the numerical expression. The numerical expression must have a value between -1 and 1. The result is dependent on the adjusted angle mode.
Example:	PRINT ARCCOS(-0.5) DEG PRINT ARCCOS(1)
Result:	2.0943951023932 0
See also:	DEG RAD

	ARCCOT
Type:	Function
Syntax:	ARCCOT(<num.expression>)
Explanation:	Calculates the arcus cotangent of the numerical expression. The result is dependent on the adjusted angle mode (see DEG, RAD).
Example:	PRINT ARCCOT(5) DEG PRINT ARCCOT(1)
Result:	0.197395559849881 45
See also:	DEG RAD

	ARCOTH
Type:	Function
Syntax:	ARCOTH(<num.expression>)
Explanation:	Calculates the area (inverse) hyperbolic cotangent of the numerical expression. The numerical value must be outside of the number interval -1 to 1.
Example:	PRINT ARCOTH(5)
Result:	0.202732554054082

	ARCSIN
Type:	Function
Syntax:	ARCSIN(<num.expression>)
Explanation:	Calculates the arcus sine of the numerical expression. The numerical expression must have a value between -1 and 1. The result is dependent on the adjusted angle mode. (See also, DEG, RAD)
Example:	PRINT ARCSIN(1) DEG PRINT ARCSIN(0.5)
Result:	1.5707963267949 30

	ARCTAN
Type:	Function
Syntax:	ARCTAN(<num.expression>)
Explanation:	Calculates the arcus tangent of the numerical expression. ARCTAN is identical to ATN. The result is dependent on the adjusted angle mode.
Example:	PRINT ARCTAN(-1) DEG PRINT ARCTAN(1)
Result:	-0.785398163397448 45

	ARSINH
Type:	Function
Syntax:	ARSINH(<num.expression>)
Explanation:	Calculates the area (inverse) hyperbolic sine of the numerical expression.
Example:	PRINT ARSINH(-1)
Result:	-0.881373587019543

	ARTANH
Type:	Function
Syntax:	ARTANH(<num.expression>)
Explanation:	Calculates the area (inverse) hyperbolic tangents of the numerical expression. The numerical expression must have a value between -1 and 1.
Example:	PRINT ARTANH(0.5)
Result:	0.549306144334055

	ASC
Type:	Function
Syntax:	ASC(<string expression>)
Explanation:	Determines the ASCII value of the first character of the string expression. ASC is the reverse function of CHR$. For more information, turn to the ASCII table in the appendix. Caution: If A$ is an empty string, the call ASC(A$) returns zero if the nonfatal error messages have been turned off (Error_messages 0) and leads to the message "Illegal function call" if not.
Example:	PRINT ASC("abc") PRINT ASC( CHR$(24))
Result:	97 24
See also	CHR$

	ATN
Type:	Function
Syntax:	ATN(<num.expression>)
Explanation:	Calculates the arcus tangent of the numerical expression. ATN is identical to ARCTAN. The result is dependent on the adjusted angle mode (see DEG, RAD).
Example:	PRINT ATN(-1) DEG PRINT ATN(1)
Result:	-0.785398163397448 45

	BACKUP
Type:	Command
Syntax:	BACKUP(<string expression>) BACKUP(<file name>)
Explanation:	Creates a backup copy from a file. The backup copy receives the extension "BAK" and is posted in the same folder. The FileSpecificationRecord must contain such a <file name> as it is returned e.g., from FILESELECT or FN Get_Fsspec$ from the Extension Library. Wildcard characters are not permitted in the file. If the file cannot be found, the command is cancelled. An error message is issued if Error_Messages is activated.
Example:	BACKUP Fn GetFsspec$(0,0,"OmikronBasic")
Result:	A file copy with the name OmikronBasic.BAK is generated from the file OmikronBasic.
See also	COPY

	BIN$
Type:	Function
Syntax:	BIN$(<num.expression>)
Explanation:	The numerical expression is converted into a character string, which represents the rounded value of the expression as a binary number. First, the numerical expression is always converted to the long integer format. A value with a too large amount generates an "Integer overflow" error message, if the FPU Exceptions were previously activated with the compiler control word "FPUEXON."
Example:	PRINT BIN$(4) PRINT BIN$(24) PRINT BIN$(1E+10)
Result:	%100 %11000 Integer overflow in line no. 2
See also:	OCT$ HEX$ STR$ VAL

	BIOS
Explanation:	Has no application purpose in Omikron Basic 6 and is ignored by the compiler. Please, do not use.

	BIT
Type:	Function
Syntax:	BIT(<num.expression>,<num.expression>) BIT(<bit number>,<value>)
Explanation:	The rounded value is converted to a 32-digit binary number. If the amount of a value is too large, it will generate the error message "Integer overflow" if the FPU exceptions were turned on with the compiler control word "FPUEXON." The function returns -1, if the bit on the right of the binary number is set, otherwise, 0. The bit with the lowest value has the number 0. The bit with the highest value has the number 31 and represents the sign in case of signed numbers. An erroneous bit number generates the error message "Illegal vunction call" if monitoring of the range control was previously activated using COMPILER "RCON."
Example:	PRINT BIT(0,1) PRINT BIT(2,1) PRINT BIT(31,-1) PRINT BIT(12,-1)
Result:	-1 0 -1 -1
See also:	BIT as a command

	BITBLT
Type:	Command
Syntax:	BITBLT<num.expression>[,<num.expression>,<num.expression>,<num.expression>] TO <num.expression>[,<num.expression>,<num.expression>,<num.expression>] [;<num.expression>] BITBLT <num.expression>TO <num.expression>,COLOR <num.expression> 1: BITBLT <X1>,<Y1>,<width>,<height> TO <X2>,<Y2>,<width2>, <height2>[;<mode>] 2: BITBLT <X>,<Y>,<width>,<height>TO <memory address>[;<mode>] 3: BITBLT <memory address>TO <X>,<Y>,<width>,<height>[;<mode>] 4: BITBLT <memory address1>TO <memory address2>,COLOR <color>
Explanation:	Copies a rectangular screen section depending on syntax: 1: from screen to screen 2: from screen to memory 3: from memory to screen 4: from memory to memory Source and target oblongs can differ in size. The source image is modified by the command in such a way as to fit it exactly into the target oblong. Therefore, the BITBLT command can also be used for the purpose of enlarging, reducing, or distorting images. In the case of syntax 1 to 3, the specification of a mode is possible as well, which allows for a point by point linking of the image information between source and target: MODE 0: Target = Source MODE 1: Target = Source AND Target MODE 2: Target = NOT (Source XOR Target) MODE 3: Target = NOT Target OR Source MODE 4: Target = NOT Source MODE 5: Target = NOT Target AND Source MODE 6: Target = Source XOR Target MODE 7: Target = Source OR Target MODE 32: Target = (Source + Target)\2 MODE 33: Target = MIN($FFFF, Source + Target) MODE 34: Target = (Source + Target) MOD $FFFF MODE 35: Target = MAX(0, Source - Target) MODE 36: Target = Source, if source is not white (transparent mode) MODE 37: Target = MAX(Source, Target) MODE 38: Target = (Source - Target + $FFFF) MOD $FFFF MODE 39: Target = MIN (Source, Target) Each Source and Target represent a 6-byte RGB Record whereby R=Red, G=Green, and B=Blue can consist of values between 0 and $FFFF. If the specification <mode> is omitted, the process is performed according to 'MODE 0'. Any bit block transfer send to the screen takes a defined graphics window into consideration (see CLIP). In the syntax BITBLT Adr1 TO Adr2, COLOR P indicates P, how many color planes the target image should have. Therefore, this command can be used in order to modify the pixel depth of an image. The memory requirements for a BITBLT to memory can be calculated as follows: Memory requirement = 6+((width+15) * height * color planes) SHR 3 The leading three words consist of the following: 1. Number of color planes 2. Width in pixels 3. Height in pixels
Example:	Screen_Buffer= MEMORY(6+((60+15)408) SHR 3):'with 256 colors PELLIPSE 50,50,30,20 BITBLT 25,20,50,50 TO Screen_Buffer WAIT .5 CLS BITBLT Screen_Buffer TO 20,20,50,50 WAIT .5 BITBLT 20,20,50,50 TO 20,30,50,50,6 WAIT .5 PCIRCLE 45,55,8
Result:	First, a screen buffer is created using MEMORY. After this, an ellipse is drawn and transferred to the buffer using BITBLT. After the screen was cleared, the ellipse is now again loaded from the buffer and then once again copied to the screen. Finally, a circle is drawn.
See also:	BLOAD BSAVE

	BLOAD
Type:	Command
Syntax:	BLOAD <string expression>[,<num.expression>] BLOAD <file name>[,<start address>]
Explanation:	The indicated file is loaded into memory commencing at the start address. If this expression is missing, the output is directed to the screen (logical screen address) and to the uppermost Omikron Basic output window (if one is open), respectively. In this case, width, height, and pixel depth are adapted automatically. For this purpose, the file must be available in the PICT format such as it is e.g., automatically created by BSAVE. PICT files created with other programs can be loaded with BLOAD as well. Caution: You have to take care, that enough memory is reserved at <start address> for receiving the whole file. Otherwise a crash would be propably the result.
Example:	Mem= MEMORY(100) BLOAD FN Get_Fsspec$(0,0,"EXAMPLE.DAT"),Mem
Result:	Memory is first reserved. The file EXAMPLE.DAT is then loaded into memory.
See also:	BSAVE BITBLT

	BOX
Type:	Command
Syntax:	BOX <num.expression>,<num.expression>{TO <num.expression>,<num.expression>\|,<num.expression>,<num.expression>} BOX <X>,<Y>{TO <X2>,<Y2>\|<width>,<height>}
Explanation:	Draws an unfilled oblong on the screen. Hereby, either two opposite corners are to be indicated or a corner, width, and height of the oblong. Color, line style, and width can be determined using LINE COLOR, LINE STYLE, and LINE WIDTH respectively. A window defined by CLIP, is not drawn outside of this area.
Example:	BOX 20,30,70,40
Result:	Draws an oblong
See also:	PBOX PRBOX RBOX

	BRK
Type:	Command
Syntax:	BRK
Explanation:	This command is used exclusively for the error location in compiled programs. It triggers a jump in the compiled product to the debugger. Of course, that is only possible if a debugger was started before, otherwise, the Mac crashes with the message "Unimplemented Trap." This command offers the opportunity to interrupt a program at a specific location so as to initiate the search for errors with a debugger on an object code level.
Example:
Result:

	BSAVE
Type:	Command
Syntax:	BSAVE <string expression>[,<num.expression>,<num.expression>] BSAVE <file name>[,<start address>,<length>]
Explanation:	Saves the memory area starting at <start address> under the <file name>. If <start address> and <length> are missing, the screen and the uppermost Omikron Basic output window, respectively, are stored instead. In this case, the save procedure occurs in the PICT format, whereby it is possible to load the image to any graphics port with BLOAD or to process it further with another program.
Example:	BSAVE FN Get_Fsspec$(0,0,"Screen.PICT")
Result:	The contents of the screen buffer are transferred to the file Screen.PICT.
See also:	BITBLT BLOAD

	CALL
Type:	Command
Syntax:	CALL <num.variable>[(][L ]<num.expression>][[, [L ]<num.expression>]])]
Explanation:	A machine language subroutine is called. The start address is supplied by the numerical variable. The following expressions are passed to the stack in reverse order, i.e., the first parameter is at the bottom of the stack, that is, at "0,R31". The expressions may be preceded by an "L" in order to pass the appropriate parameter as long integers. Otherwise, a short integer is always passed. Only those registers declared by Apple as 'volatile' may be modified. They are as follows: R0,R3-R12 FPR0-FPR13 CR0,CR1,CR5-CR7 R31 points to the dynamic stack on which the passed parameters are located. The program must end with 'Blr'. If the link register is modified, it is to be ensured that it is restored again before the return. At the completion of the machine program, the contents of R3 can be loaded with RESERVED(0). Errors caused by the machine program cannot be intercepted by Omikron Basic. Therefore, starting a suitable debugger in the test phase first is recommended.
Example:	Test$= "PNJLSPO/TPGUXBSF" CALL Decode (L &Test$, 1) 'Pass pointer to Test$ and "1" PRINT Test$ The machine program: (Was created with the Assembler Library for Omikron Basic 6.) Lwz R6,0,R31:'Load pointer to string Lhz R4,4,R31:'Load parameter (the "1") Lwz R7,0,R6:'Generate pointer to string segment Lwz R3,4,R6:'Length of string Subi R7,R7,1 Mtctr R3 Label "loop" Lhz R5,1,R7:'Load a character of the string Sub R5,R5,R4:' Modify character Stbu R5,1,R7:'And return character Bdnz_ "loop":For all characters of the string Blr
Result:	Omikron.SOFTWARE

	CASE
Type:	Command
Syntax:	CASE <expression>[TO <expression>][[,<expression> [TO <expression>]]]
Explanation:	Within a SELECT ... CASE statement, CASE introduces a partial branch. This program branch is then carried out if one of the indicated possibilities applies to the variable mentioned in the case of SELECT. Several possibilities are simply listed separated by commas. Intervals are also possible using TO. In the case of strings, only the first 4 bytes are parsed.
Example:
Result:
See also	SELECT DEFAULT OTHERWISE

	CDBL
Type:	Function
Syntax:	CDBL(<num.expression>)
Explanation:	Converts any numerical expression to a double precision floating point format.
Example:	A!=1 B!=3 PRINT CDBL(A!/B!) PRINT CDBL(A!)/CDBL(B!)
Result:	0.333333333333333 0.333333333333333
See also:	CINT CINTL CSNG

	CHAIN
Explanation:	Has no application purpose in Omikron Basic 6 and is ignored by the compiler. Please, do not use.

	CHDIR
Type:	Command
Syntax:	CHDIR <string expression>
Explanation:	Changes the default path to the path indicated in <string expression>. Such a FileSpecificationRecord must be passed to the command as is returned e.g., by FILESELECT or FN Get_Fsspec$ from the Extension Library.
Example:	CHDIR FN Get_Fsspec(0,0,"MacintoshHD:Omikron Basic:Programe:")
Result:	The specified path becomes the current path.

	CINT
Type:	Function
Syntax:	CINT(<num.expression>)
Explanation:	Converts any numerical value to the short integer format (integers of -32768 to +32767). Of course, the definition range of the function especially encompasses the range of short integer numbers. Other values lead to the error message "Integer overflow" if range control monitoring was previously activated using COMPILER "RCON."
Example:	A=1 B=3 PRINT CINT(A/B) PRINT CINT(A)/CINT(B) PRINT CINT(40000)
Result:	0 0.333333333333333 Integer overflow in line no. 4
	CINTL CSNG CDBL