M. Amer Iqbal Qureshi

SHOut SER,SRCLK, lsbfirst

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Amer Iqbal - Teach Yourself PIC Microcontrollers for Absolute Beginners-Microtronics Pakistan (2001)

Symbol
High
SHOut

SHOut SER,SRCLK,
lsbfirst
,[%00000000,%00000000,%00000000,%00000000]
' send data
Device=
18f452
XTAL
=20
ALL_DIGITAL
=true
Output
PORTB
Input
PORTA
Symbol SER =
PORTB
.0
' Serial data Pin
Symbol SRCLK =
PORTB
.1
' Serial data Clock Pin
Symbol SRClr =
PORTB
.2
' Serial data Clear
Symbol Latch =
PORTB
.3
' Columns, Latch
Symbol RowClk =
PORTB
.4
' Row clock, to select new row
Symbol Rowrst =
PORTB
.5
' Row reset, selects row 0
High SRClr
' Turn off the serial register clear
PulsOut Rowrst,2
' give a pulse on row reset pin, to select row 0
SHOut SER,SRCLK,
lsbfirst
,[%11111110,%11111111,%11111111,%11111111]
' send data
on serial pin
PulsOut Latch,4
End
Fig. 6 Single LED is ON

Teach Yourself PIC Microcontrollers | www.electronicspk.com | 141
on serial pin
Now lets send some pattern, to show this
effect.
SHOut SER,SRCLK,
lsbfirst
,[%
11111110,%10101010,%11001100,%
00011100]
Notice the data, being sent, and the
appearance of ON LEDs in Fig. 8. this
clearly shows that the first byte sent, goes
to extreme right, and last byte sent goes to extreme left.
If we want to reverse the pattern , we can send Most significant bit first.
Blinking an LED
In order to make an LED Blink, you have to turn the corresponding column On, and OFF repeatedly after a
set interval.

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