Segment Tags

Schematic

2005-12-15T01:49:00.000-05:00

Prototype Photos :: 12.11.05

2005-12-12T02:52:00.000-05:00

Perf board and breadboard prototypes from earlier this weekend. And. a picture of my because Jenny says we need one of those here too. Personally, I don't believe her.

code for the pic

2005-12-10T17:34:00.000-05:00

here's the working code for our project. This version has scrolling. you can end the scrolling by pressing any button.

'****************************************************************
'* Name : sevenSegmentCounter_wEdgeDetection.bas *
'* Author : Jenny Chowdhury &MichaelDelGadudio & Karl Channell *
'* : All Rights Reserved *
'* Date : 12/10/2005 *
'* Version : 1.0 *
'* Notes : seven segment display counter using edge *
'* : detection *
'****************************************************************

DEFINE OSC 4
' Set all of PORTB to outputs
TRISB = %00000000

'Set all A ports as digital
adcon1 = %00000110

TRISA = %00000000
TRISD = %00000000

'set buttons as input ports
input PORTB.7 'curser button
input PORTC.7 'forward alphabet
input PORTC.6 'backwards alphabet

'set pins as write control
output PORTC.5 'write control for 1st display
output PORTC.4 'write control for 2nd display
output PORTD.7 'write control for 3rd display

output portc.2 ' address pin for 1st display
output portc.3 ' address pin for 1st display

output PORTC.0 ' address pin for 2nd display
OUTput PORTC.1 ' address pin for 2nd display

output PORTE.1 'address pin for 3rd display
output PORTE.2 'address pin for 3rd display

timer var byte
timer = 0

myDigit var byte[12]
j var byte ' counter for for loops

'initialize letters
FOR j=0 to 11 STEp 1
myDigit[j] = j
next j

alphabet var BYTE[27]
alphabet[0] = "A"
alphabet[1] = "B"
alphabet[2] = "C"
alphabet[3] = "D"
alphabet[4] = "E"
alphabet[5] = "F"
alphabet[6] = "G"
alphabet[7] = "H"
alphabet[8] = "I"
alphabet[9] = "J"
alphabet[10] = "K"
alphabet[11] = "L"
alphabet[12] = "M"
alphabet[13] = "N"
alphabet[14] = "O"
alphabet[15] = "P"
alphabet[16] = "Q"
alphabet[17] = "R"
alphabet[18] = "S"
alphabet[19] = "T"
alphabet[20] = "U"
alphabet[21] = "V"
alphabet[22] = "W"
alphabet[23] = "X"
alphabet[24] = "Y"
alphabet[25] = "Z"
alphabet[26] = " "

' --- Edge Detection vars for cursor ---'
switchStateVar var byte
switchStateVar = 0
lastSwitchStateVar var byte
switchCountVar var byte
switchCountVar = 0

' --- Edge Detection vars for alpha ---'
alphaSwitchStateVar var byte
alphaswitchStateVar = 0
alphaLastSwitchStateVar var byte
alphaSwitchCountVar var byte

' --- Edge Detection vars for backwards alpha ---'
backAlphaSwitchStateVar var byte
backAlphaswitchStateVar = 0
backAlphaLastSwitchStateVar var byte
backAlphaSwitchCountVar var byte

' Display 1
' PIC B0-B6 maps to 1414 D0-D6
' -- Set the initial display state -- '

gosub reset

MAIN:

' -- Edge detection for cursor --'
switchStateVar = PORTB.7
if switchStateVar <> lastswitchStateVar THEN
timer = 0
if switchStateVar = 1 then
' the switch went from off to on
switchCountVar = switchCountVar + 1
switchCountVar = (switchCountVar//12)

high PORTD.2
' clear it all out
gosub reset
else
' the switch went from on to off
' test pin
low PORTD.2
endif
' store the state of the switch for next check:
lastswitchStateVar = switchStateVar
else
'increment the timer
timer = timer + 1
if timer >= 100 then
while (switchStateVar = lastswitchStateVar && alphaswitchStateVar = alphalastswitchStateVar && backAlphaswitchStateVar = backAlphalastswitchStateVar)

gosub scroll
switchStateVar = PORTB.7
alphaSwitchStateVar = PORTC.7
backAlphaswitchStateVar = PORTC.6

wend
endif

endif

' -- Edge detection for forward alphabet button --'
alphaswitchStateVar = PORTC.7
if alphaswitchStateVar <> alphalastswitchStateVar THEN
timer = 0

' the switch went from off to on
if alphaswitchStateVar = 1 then
'increment the current digit

for j= 0 to 11 step 1
If(switchcountvar = j) then
mydigit[j] = mydigit[j]+1
myDigit[j] = myDigit[j]//27
Endif
next j

' clear it all out
gosub reset
else 'the switchpin went off

endif
' store the state of the switch for next check:
alphalastswitchStateVar = alphaswitchStateVar
endif

'backbutton edge detection
' -- Edge detection for backwards alphabet button --'
backAlphaswitchStateVar = PORTC.6
if backAlphaswitchStateVar <> backAlphalastswitchStateVar THEN

timer = 0
' the switch went from off to on
if backAlphaswitchStateVar = 1 then
'increment the current digit

for j= 0 to 11 step 1
If(switchcountvar = j) then
mydigit[j] = mydigit[j] + 26
myDigit[j] = myDigit[j]//27
Endif
next j

' clear it all out
gosub reset
else
' the switch went from on to off

endif
' store the state of the switch for next check:
backAlphalastswitchStateVar = backAlphaswitchStateVar
endif

'Letters are written right to left thus digit 3 appears first and so on
'Display three

'end of display three
if switchCountVar = 11 then

High PORTD.7
' Digit 0C
Low PORTE.1
LOW PORTE.2
'_
PORTD = alphabet[myDigit[11]]
low PORTD.7

pause 50

High PORTD.7
' Digit 0C
Low PORTE.1
LOW PORTE.2
'_
PORTD = " "
low PORTD.7

pause 50

endif

if switchCountVar = 10 then

High PORTD.7
' Digit 1c
high PORTE.1
LOW PORTE.2
'_
PORTD = alphabet[myDigit[10]]
low PORTD.7

pause 50

High PORTD.7
' Digit 1c
high PORTE.1
LOW PORTE.2
'_
PORTD = " "
low PORTD.7

pause 50

endif

if switchCountVar = 9 then

High PORTD.7
' Digit 2c
low PORTE.1
high PORTE.2
'_
PORTD = alphabet[myDigit[9]]
low PORTD.7

pause 50

High PORTD.7
' Digit 2c
low PORTE.1
high PORTE.2
'_
PORTD = " "
low PORTD.7

pause 50

endif

''put in 8
if switchCountVar = 8 then

High PORTD.7
' Digit 3c
high PORTE.1
high PORTE.2
'_
PORTD = alphabet[myDigit[8]]
low PORTD.7

pause 50

High PORTD.7
' Digit 3c
high PORTE.1
high PORTE.2
'_
PORTD = " "
low PORTD.7

pause 50

endif

' Display two

if switchCountVar = 7 then

High PORTC.4
' Digit 0B
Low PORTC.2
LOW PORTC.3
'_
PORTA = alphabet[myDigit[7]]
low PORTC.4

pause 50

High PORTC.4
' Digit 0B
Low PORTC.2
LOW PORTC.3
'_
PORTA = " "
low PORTC.4

pause 50

endif

if switchCountVar = 6 then

High PORTC.4
' Digit 1B
high PORTC.2
LOW PORTC.3
'_
PORTA = alphabet[myDigit[6]]
low PORTC.4

pause 50

High PORTC.4
' Digit 1B
high PORTC.2
LOW PORTC.3
'_
PORTA = " "
low PORTC.4

pause 50

endif

if switchCountVar = 5 then

' Digit 2B
High PORTC.4
' Digit 2B
LOw PORTC.2
high PORTC.3
'_
PORTA = alphabet[myDigit[5]]
low PORTC.4

pause 50

High PORTC.4
' Digit 2B
low PORTC.2
high PORTC.3
'_
PORTA = " "
low PORTC.4

pause 50

endif

if switchCountVar = 4 then

' Digit 3B

High PORTC.4
' Digit 3B
high PORTC.2
high PORTC.3
'_
PORTA = alphabet[myDigit[4]]
low PORTC.4

pause 50

High PORTC.4
' Digit 3B
high PORTC.2
high PORTC.3
'_
PORTA = " "
low PORTC.4

pause 50

endif

' Display One

if switchCountVar = 3 then

High PORTC.5
' Digit 0
Low PORTC.0
LOW PORTC.1
'_
PORTB = alphabet[myDigit[3]]
low PORTC.5

pause 50

High PORTC.5
' Digit 0
Low PORTC.0
LOW PORTC.1
'_
PORTB = " "
low PORTC.5

pause 50

endif

if switchCountVar = 2 then

High PORTC.5
' Digit 1
high PORTC.0
LOW PORTC.1
'_
PORTB = alphabet[myDigit[2]]
low PORTC.5

pause 50

High PORTC.5
' Digit 1
high PORTC.0
LOW PORTC.1
'_
PORTB = " "
low PORTC.5

pause 50

endif

if switchCountVar = 1 then

' Digit 2

High PORTC.5
' Digit 2
LOw PORTC.0
high PORTC.1
'_
PORTB = alphabet[myDigit[1]]
low PORTC.5

pause 50

High PORTC.5
' Digit 2
low PORTC.0
high PORTC.1
'_
PORTB = " "
low PORTC.5

pause 50

endif

if switchCountVar = 0 then

' Digit 3
'letter3 = alphabet[myDigit[0]]

High PORTC.5
' Digit 3
high PORTC.0
high PORTC.1
'_
PORTB = alphabet[myDigit[0]]
low PORTC.5

pause 50

High PORTC.5
' Digit 3
high PORTC.0
high PORTC.1
'_
PORTB = " "
low PORTC.5

pause 50

endif

goto main

'This subroutine resets all digits on both displays
reset:
' Start Write
high PORTC.5
' Digit 0
Low PORTC.0
LOW PORTC.1
'_
PORTB = alphabet[mydigit[3]]
' End Write
low PORTC.5

' Start Write
high PORTC.5
' Digit 0
high PORTC.0
LOW PORTC.1
'_
PORTB = alphabet[mydigit[2]]
' End Write
low PORTC.5

' Start Write
high PORTC.5
' Digit 0
Low PORTC.0
high PORTC.1
'_
PORTB = alphabet[mydigit[1]]
' End Write
low PORTC.5

' Start Write
high PORTC.5
' Digit 0
high PORTC.0
high PORTC.1
'_
PORTB = alphabet[mydigit[0]]
' End Write
low PORTC.5

'send letters to 2nd output display

' Start Write
high PORTC.4
' Digit 0b
Low PORTC.2
LOW PORTC.3
'_
PORTA = alphabet[mydigit[7]]
' End Write
low PORTC.4

' Start Write
high PORTC.4
' Digit 0
high PORTC.2
LOW PORTC.3
'_
PORTA = alphabet[mydigit[6]]
' End Write
low PORTC.4

' Start Write
high PORTC.4
' Digit 0
Low PORTC.2
high PORTC.3
'_
PORTA = alphabet[mydigit[5]]
' End Write
low PORTC.4

' Start Write
high PORTC.4
' Digit 0
high PORTC.2
high PORTC.3
'_
PORTA = alphabet[mydigit[4]]
' End Write
low PORTC.4

'send 3rd output display

' Start Write
high PORTD.7
' Digit 0
Low PORTE.1
LOW PORTE.2
'_
PORTD = alphabet[mydigit[11]]
' End Write
low PORTD.7

' Start Write
high PORTD.7
' Digit 0
high PORTE.1
LOW PORTE.2
'_
PORTD = alphabet[mydigit[10]]
' End Write
low PORTD.7

' Start Write
high PORTD.7
' Digit 0
Low PORTE.1
high PORTE.2
'_
PORTD = alphabet[mydigit[9]]
' End Write
low PORTD.7

' Start Write
high PORTD.7
' Digit 0
high PORTE.1
high PORTE.2
'_
PORTD = alphabet[mydigit[8]]
' End Write
low PORTD.7

return

'This subroutine scrolls all digits
scroll:

i var byte

scroller var byte [36]

scroller[0] = " "
scroller[1] = " "
scroller[2] = " "
scroller[3] = " "
scroller[4] = " "
scroller[5] = " "
scroller[6] = " "
scroller[7] = " "
scroller[8] = " "
scroller[9] = " "
scroller[10] = " "
scroller[11] = " "
scroller[12] = alphabet[mydigit[0]]
scroller[13] = alphabet[mydigit[1]]
scroller[14] = alphabet[mydigit[2]]
scroller[15] = alphabet[mydigit[3]]
scroller[16] = alphabet[mydigit[4]]
scroller[17] = alphabet[mydigit[5]]
scroller[18] = alphabet[mydigit[6]]
scroller[19] = alphabet[mydigit[7]]
scroller[20] = alphabet[mydigit[8]]
scroller[21] = alphabet[mydigit[9]]
scroller[22] = alphabet[mydigit[10]]
scroller[23] = alphabet[mydigit[11]]
scroller[24] = " "
scroller[25] = " "
scroller[26] = " "
scroller[27] = " "
scroller[28] = " "
scroller[29] = " "
scroller[30] = " "
scroller[31] = " "
scroller[32] = " "
scroller[33] = " "
scroller[34] = " "
scroller[35] = " "

FOR i=0 to 23 STEp 1

gosub checkinput
if (switchStateVar <> lastswitchStateVar || alphaswitchStateVar <> alphalastswitchStateVar || backAlphaswitchStateVar <> backAlphalastswitchStateVar) then
timer = 0
return

endif

' Start Write
high PORTC.5
' First Letter
high PORTC.0
high PORTC.1
'_
PORTB = scroller[i]
' End Write
low PORTC.5

' Start Write
high PORTC.5
' Second Letter
low PORTC.0
high PORTC.1
'_
PORTB = scroller[i+1]
' End Write
low PORTC.5

' Start Write
high PORTC.5
' Third Letter
high PORTC.0
low PORTC.1
'_
PORTB = scroller[i+2]
' End Write
low PORTC.5

' Start Write
high PORTC.5
' Fourth Letter
low PORTC.0
low PORTC.1
'_
PORTB = scroller[i+3]
' End Write
low PORTC.5

'send letters to 2nd output display

' Start Write
high PORTC.4
' Fifth Letter
high PORTC.2
high PORTC.3
'_
PORTA = scroller[i+4]
' End Write
low PORTC.4

' Start Write
high PORTC.4
' Sixth Letter
low PORTC.2
high PORTC.3
'_
PORTA = scroller[i+5]
' End Write
low PORTC.4

' Start Write
high PORTC.4
' Seventh Letter
high PORTC.2
low PORTC.3
'_
PORTA = scroller[i+6]
' End Write
low PORTC.4

' Start Write
high PORTC.4
' Eigth Letter
low PORTC.2
low PORTC.3
'_
PORTA = scroller[i+7]
' End Write
low PORTC.4

'send 3rd output display

' Start Write
high PORTD.7
' Ninth Letter
high PORTE.1
high PORTE.2
'_
PORTD = scroller[i+8]
' End Write
low PORTD.7

' Start Write
high PORTD.7
' Tenth Letter
low PORTE.1
high PORTE.2
'_
PORTD = scroller[i+9]
' End Write
low PORTD.7

' Start Write
high PORTD.7
' Eleventh Letter
high PORTE.1
low PORTE.2
'_
PORTD = scroller[i+10]
' End Write
low PORTD.7

' Start Write
high PORTD.7
' Twelveth Letter
low PORTE.1
low PORTE.2
'_
PORTD = scroller[i+11]
' End Write
low PORTD.7

pause 200

next i
return

'this subroutine updates button values
checkinput:

switchStateVar = PORTB.7
alphaSwitchStateVar = PORTC.7
backAlphaswitchStateVar = PORTC.6
return

next on the agenda

2005-12-07T13:37:00.000-05:00

Michael and I have succesfully programmed 2 segment displays to be controlled by one pic. This "control" consists of the following:

1) cursor selection - allows user to choose the location of specfic letter he/she is changing with a press of a button.
2) forward scrolling letter selection - allows user to choose which letter for that particular spot(selected with the cursor button) with a button which makes letters appear in alphabetical order
3) backwards scrolling letter selection - allows user to choose which letter for that particular spot with a button which makes letters appear in reverse alphabetical order.

The code is really ugly and long because it's procedural. Apparenlty you can't do the OOP thing with pic basic pro. Or even pass parameters to subroutines for that matter.

Meanwhile, Karl has been working on getting the text to scroll across the segment.

Today, we'll be working on getting a third segment on the pic, getting scrolling to occur after an idle period and generally, making our code uglier and longer.

Michael talked to Todd about buying back the other segment displays yesterday so hopefully, we can get start soldering before long.

Also, I called Jameco to today to yet again tell them about their duplication error. I really had hoped that they would send me a shipping label as I have no time to go to the post office. I couldn't convince the rep though.

some photos from the first prototype

2005-12-07T13:32:00.000-05:00

Summary

2005-12-06T12:51:00.000-05:00

Segment Tags aim to allow for the personalization of space and objects in an environment. Through the use of interactive displays users can create their own tag or message without the destruction of property. Visitors of a restaurant, bar, or public space are encourage to leave a word, thought, question or message of what's on heir mind with relation to their surroundings. The intent is to open a dialog between visitors who share a space at different times.

Walls, furniture, and objects don't commonly allow people to leave their mark or capture a thought. The desire for people to leave traces of their presence can be seen in graffiti, guest books, customized cars, blogs, and bumper, where we leave behind signs that we have been someplace and have something to say. As individuals, we desire the ability to leave a bit of our selves in an environment. Segment Tags bridge this gap by providing people the opportunity to leave a few words behind.

PIC Code and the 1414

2005-12-03T19:47:00.000-05:00

Yesterday Jenny Karl and I worked mainly on the software side. Karl worked on making the text display scrollable, while Jenny and I worked on implementing edge detection for the cursor and letter selection. One big ah-ha happened when we realized that the decoder in the 1414 cal translate string character like "A". This saves a lot of time because we no longer need to send the IC binary.

1414 Smart Display Photos

2005-12-01T17:39:00.000-05:00

On top: Karl & Jenny setting up the 1414 on the board. On the bottom: The 1414 smart 16-segment display. This display is great. It's easy to setup and easy to send data to. ASCII characters are sent to the display where they are decoded, stored in memory, and multiplexed. The character size is small but the LEDs are bright and make up for their size in brightness.

Research

2005-11-29T02:58:00.000-05:00

A compilation of resources for setting up 7 and 16-segment displays and drivers. Practical Electronics for Inventors gives a great explanation of displays in the appendix. We've been working with 7-segment and 16-segment LED displays.

Display Drivers/ICs
MM5450 :: 7-Segment LED display driver. We set this chip up to drive up four seven shipment displays. Multiplexing needs to be used in order to drive eight displays instead of just the four.
MAX6954 :: 16-Segment LED display driver can power up to eight displays (on order)
Allegro shift register - ...

Displays
Seven segment from Radio Shack
Dual seven segment
Sixteen segment display
HPDL1414 :: "Smart" Alphanumeric Display include embedded IC, driver, latch decoder and character fonts (ordered waiting for delivery).

Resources
Maxim 16-Segment display tutorial

Setup

2005-11-28T19:33:00.000-05:00

The blog documenting our Physical Computing final is alive and well. Even though there are only a few weeks Left tin the semester, capturing what we do is important. Instead of creating a documentation page for the project, it's easier to create something we can all edit.