27220 Parallax Inc, 27220 Datasheet - Page 145

• Manufacturer Part Number: 27220
• Description: BOOK STAMPWORKS
• Manufacturer: Parallax Inc

Specifications of 27220

• Accessory Type: Booklet
• Product: Microcontroller Accessories
• Lead Free Status / RoHS Status: Not applicable / Not applicable
• For Use With/related Products: StampWorks
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant, Not applicable / Not applicable

To connect cascaded 74HC595s, the clock and latch lines are all tied together and
the QH’ serial output from one stage connects to the serial input of the next stage.
Program: SW21-EX23-74HC595-2.BS2
' {$STAMP BS2}
' {$PBASIC 2.5}
' -----[ Program Description ]---------------------------------------------
'
' This program demonstrates a simple method of turning three BASIC Stamp
' I/O pins into sixteen digital outputs with a 74HC595 shift register.
' -----[ I/O Definitions ]-------------------------------------------------
Clock
SerData
Latch
' -----[ Constants ]-------------------------------------------------------
DelayTime
' -----[ Variables ]-------------------------------------------------------
counter
pattern
' -----[ Initialization ]--------------------------------------------------
Reset:
' -----[ Program Code ]----------------------------------------------------
Main:
LOW Latch
pattern = %00000001
DO
LOOP UNTIL (pattern = %10000000)
DO
counter = counter + 1
GOSUB Out_595x2
PAUSE DelayTime
pattern = pattern << 1
counter = counter + 1
PIN
PIN
PIN
CON
VAR
VAR
0
1
2
100
Byte
Byte
' shift clock (74HC595.11)
' serial data (74HC595.14)
' output latch (74HC595.12)
' binary counter
' zig-zag pattern
' make output and low
' update counter
' put pattern on 74x595
' hold
' shift pattern left