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© MCS Electronics, 1995-2007

Action

Shift the cursor of the LCD display left or right by one position.

Syntax

SHIFTCURSOR LEFT | RIGHT

See also

SHIFTLCD

Partial Example

LCD "Hello"

SHIFTCURSOR LEFT

End

SHIFTIN

Action

Shifts a bit stream into a variable.

Syntax

SHIFTIN pin , pclock , var , option [, bits , delay ]

Remarks

Pin

The port pin which serves as an input.PINB.2 for example

Pclock

The port pin which generates the clock.

Var

The variable that is assigned.

Option

Option can be :

 

0

– MSB shifted in first when clock goes low

 

1

– MSB shifted in first when clock goes high

 

2

– LSB shifted in first when clock goes low

 

3

– LSB shifted in first when clock goes high

 

Adding 4 to the parameter indicates that an external clock signal is used for

 

the clock. In this case the clock will not be generated. So using 4 wil be the

 

same a 0 (MSB shifted in first when clock goes low) but the clock must be

 

generated by an external signal.

 

4

– MSB shifted in first when clock goes low with ext. clock

 

5

– MSB shifted in first when clock goes high with ext. clock

 

6

– LSB shifted in first when clock goes low with ext. clock

 

7

– LSB shifted in first when clock goes high with ext. clock

Bits

Optional number of bits to shift in. Maximum 255.

Delay

Optional delay in uS. When you specify the delay, the number of bits must

 

also be specified. When the number of bits is default you can use NULL for

 

the BITS parameter.

 

 

 

If you do not specify the number of bits to shift, the number of shifts will depend on the type

page -649-

© MCS Electronics, 1995-2007

of the variable.

When you use a byte, 8 shifts will occur and for an integer, 16 shifts will occur. For a Long and Single 32 shifts will occur.

The SHIFTIN routine can be used to interface with all kind of chips.

The PIN is normally connected with the output of chip that will send information.

The PCLOCK pin can be used to clock the bits as a master, that is the clock pulses will be generated. Or it can sample a pin that generates these pulses.

The VARIABLE is a normal BASIC variable. And may be of any type except for BIT. The data read from the chip is stored in this variable.

The OPTIONS is a constant that specifies the direction of the bits. The chip that outputs the data may send the LS bit first or the MS bit first. It also controls on which edge of the clock signal the data must be stored.

When you add 4 to the constant you tell the compiler that the clock signal is not generated but that there is an external clock signal.

The number of bits may be specified. You may omit this info. In that case the number of bits of the element data type will be used.

The DELAY normally consists of 2 NOP instructions. When the clock is too fast you can specify a delay time(in uS).

See also

SHIFTOUT , SHIFT

Example

'-----------------------------------------------------------------------------

 

------------

: shift.bas

'name

'copyright

: (c) 1995-2005, MCS Electronics

'purpose

: example for SHIFTIN and SHIFTOUT statement

'micro

: Mega48

'suited for demo

: yes

'commercial addon needed

: no

'-----------------------------------------------------------------------------

------------

$regfile = "m48def.dat"

' specify the used

micro

' used crystal

$crystal = 4000000

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

 

Dim L As Long

 

clock Alias Portb.0

 

Output Alias Portb.1

'watch the PIN

sinp Alias Pinb.2

instead of PORT

 

'shiftout pinout,pinclock, var,parameter [,bits , delay]

page -650-

© MCS Electronics, 1995-2007

'value for parameter :

'0 - MSB first ,clock low

'1 - MSB first,clock high

'2 - LSB first,clock low

'3 - LSB first,clock high

'The bits is a new option to indicate the number of bits to shift out

'For a byte you should specify 1-8 , for an integer 1-16 and for a long 1-32 'The delay is an optional delay is uS and when used, the bits parameter must 'be specified too!

'Now shift out 9 most significant bits of the LONG variable L

Shiftout Output , Clock , L , 0 , 9

'shiftin pinin,pinclock,var,parameter [,bits ,delay]

'0 - MSB first ,clock low (4)

'1 - MSB first,clock high (5)

' 2 - LSB first,clock low (6)

'3 - LSB first,clock high (7)

'To use an external clock, add 4 to the parameter

'The shiftin also has a new optional parameter to specify the number of bits

'The bits is a new option to indicate the number of bits to shift out

'For a byte you should specify 1-8 , for an integer 1-16 and for a long 1-32 'The delay is an optional delay is uS and when used, the bits parameter must 'be specified too!

'Shift in 9 bits into a long Shiftin Sinp , Clock , L , 0 , 9

'use shift to shift the bits to the right place in the long

Shift L , Right , 23

End

SHIFTOUT

Action

Shifts a bit stream out of a variable into a port pin .

Syntax

SHIFTOUT pin , pclock , var , option [, bits , delay ]

Remarks

Pin

The port pin which serves as a data output.

Pclock

The port pin which generates the clock.

Var

The variable that is shifted out.

Option

Option can be :

 

0

– MSB shifted out first when clock goes low

 

1

– MSB shifted out first when clock goes high

 

2

– LSB shifted out first when clock goes low

 

3

– LSB shifted out first when clock goes high

page -651-

 

© MCS Electronics, 1995-2007

 

 

 

Bits

Optional number of bits to shift out.

 

Delay

Optional delay in uS. When you specify the delay, the number of bits

 

 

must also be specified. When the default must be used you can also

 

 

use NULL for the number of bits.

 

If you do not specify the number of bits to shift, the number of shifts will depend on the type of the variable.

When you use a byte, 8 shifts will occur and for an integer, 16 shifts will occur. For a Long and Single 32 shifts will occur.

The SHIFTIN routine can be used to interface with all kind of chips.

The PIN is normally connected with the input of a chip that will receive information.

The PCLOCK pin is used to clock the bits out of the chip.

The VARIABLE is a normal BASIC variable. And may be of any type except for BIT. The data that is stored in the variable is sent with PIN.

The OPTIONS is a constant that specifies the direction of the bits. The chip that reads the data may want the LS bit first or the MS bit first. It also controls on which edge of the clock signal the data is sent to PIN.

The number of bits may be specified. You may omit this info. In that case the number of bits of the element data type will be used.

The DELAY normally consists of 2 NOP instructions. When the clock is too fast you can specify a delay time(in uS).

See also

SHIFTIN , SHIFT

Example

See SHIFTIN sample

SHIFTLCD

Action

Shift the LCD display left or right by one position.

Syntax

SHIFTLCD LEFT / RIGHT

Remarks

NONE

See also

SHIFTCURSOR

page -652-