27220 Parallax Inc, 27220 Datasheet - Page 186

• 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

' Update MC14489 configuration register
Update_Cfg:
' Update MC14489 decimal point control and segments registers
Update_Segs:
Behind the Scenes
As demonstrated in Experiment #10, 7-segment display multiplexing requires a lot of
effort that consumes most of the computational resources of the BASIC Stamp.
Enter the Motorola MC14489 display multiplexer. By using just three BASIC Stamp
I/O pins it will effectively control up to five 7-segment displays. The interface is
simple, allowing the display of numbers (all hex values), a few letters (those that can
be displayed on a 7-segment LED), and a few special characters (e.g., dash, degrees
ELSE
ENDIF
RETURN
LOW Enable
SHIFTOUT SerData, Clock, MSBFIRST, [config]
HIGH Enable
RETURN
LOW Enable
SHIFTOUT SerData, Clock, MSBFIRST, [dpCtrl\4,
HIGH Enable
RETURN
segs3 = money DIG 2
segs2 = money DIG 1
segs1 = money DIG 0
GOSUB Update_Segs
config = Blank
GOSUB Update_Cfg
config = %11101111
dpCtrl = %1000
segs5 = Blank
segs4 = Ltr_F
segs3 = Ltr_U
segs2 = Ltr_L
segs1 = Ltr_L
GOSUB Update_Segs
GOSUB Update_Cfg
segs5\4, segs4\4, segs3\4, segs2\4, segs1\4]
' dollar digit
' tens digit
' ones digit
' show "FULL"
' setup for "FULL"
' display bright, no DPs
' F
' U (Special Decode)
' L (Special Decode)
' L (Special Decode)
' show message
' display on
' enable MC14489
' send config register
' disable MC14489