bi-color T1 LED

thomas_pittin

Hi,

i want to connect this diode (Bi Color T1 3/4 LED) to my boe-bot

the question is, what is the command to control this diode

thanks
Thomas

Publison

thomas_pittin wrote: »

Hi,

i want to connect this diode (Bi Color T1 3/4 LED) to my boe-bot

the question is, what is the command to control this diode

thanks
Thomas

You will want to have a 220 Ohm resistor on the LED to the pin.

A high on the pin will light it one color, and a low will light it the other color. Which color lights will depend on the polarity.

thomas_pittin

Publison wrote: »

You will want to have a 220 Ohm resistor on the LED to the pin.

A high on the pin will light it one color, and a low will light it the other color. Which color lights will depend on the polarity.

thanks a lot
Thomas

Tracy Allen

Some bi-color LEDs have two pins, and the diodes are connected up back to back inside. The easy way to connect one of those is between two pins in series with a resistor (~220Ω). Then p0 high and p1 low gives 1 color, and vice versa the other. Both pins the same or inputs gives LEDs off.

[SIZE=1][FONT=courier new]
        220       LEDs
   p0 ---/\/\/\---o--->|----o------p1
                  |         |
                  o---|<----o
[/FONT][/SIZE]

Another configuration has 3 pins with common cathode or common anode. Does your LED have 2, or 3 wires?

thomas_pittin

Tracy Allen wrote: »

Some bi-color LEDs have two pins, and the diodes are connected up back to back inside. The easy way to connect one of those is between two pins in series with a resistor (~220Ω). Then p0 high and p1 low gives 1 color, and vice versa the other. Both pins the same or inputs gives LEDs off.

[SIZE=1][FONT=courier new]
        220       LEDs
   p0 ---/\/\/\---o--->|----o------p1
                  |         |
                  o---|<----o
[/FONT][/SIZE]

Another configuration has 3 pins with common cathode or common anode. Does your LED have 2, or 3 wires?

My LED have two wires.
i'll try your solution

thanks in advance

thomas_pittin

Now work fine

thanks

Duane C. Johnson

Hi Thomas;

Since you have the basic 2 pin circuit running there is more you can do with them.
Using a counter, in this case CTRA, to quickly switch back and forth between the pins.
Here is a code snippet writen in FemtoBasic showing how to do this.

NEW
REM FLASH A 2 PIN BI-COLORED LED WITH CTR
21  F = 53687 : REM FRQA 1000Hz      ( F = Hz * 53.6870912 )
21  F =  5369 : REM FRQA 100Hz       ( F = Hz /   80MHz * 2^32 )
21  F =   268 : REM FRQA 5Hz         ( F = Hz / 78125Hz * 2^22 )
22  E =    $0 : REM PHSA             ( don't care )
23  D =    $5 : REM CTRMODE  0 -> 31 ( NCO Differential )
24  C =    $7 : REM PLLDIV   0 ->  7 ( don't care )
25  B =    18 : REM BPIN PIN 0 -> 31 ( Connect LED To
26  A =    17 : REM APIN PIN 0 -> 31     These Two Pins )
27  O = 0
40  GOSUB 200
100 PRINT "CHOOSE 0NE OF THE 7 LED PATERNS" 
110 INPUT "0 1 2 3 4 5 6 99 ? "; X
120   IF X = 0 THEN O = 3 : F = 5369 : GOSUB 200
125   IF X = 1 THEN O = 1 : F = 5369 : GOSUB 200
130   IF X = 2 THEN O = 2 : F = 5369 : GOSUB 200
135   IF X = 3 THEN O = 0 : F = 5369 : GOSUB 200
140   IF X = 4 THEN O = 1 : F =  268 : GOSUB 200
145   IF X = 5 THEN O = 2 : F =  268 : GOSUB 200
150   IF X = 6 THEN O = 0 : F =  268 : GOSUB 200
155   IF X > 6 THEN END
190 GOTO 100
200 REM MAKE LED CHANGES
210 OUTA [B..A] = O
220 G = D SHL 26 + C SHL 23 + B SHL 9 + A
230 CTRA = G : FRQA = F
290 RETURN
RUN

In this case I have the Bicolored LED connecter between pins 18 and 17, but any two pins can be used.
Switching at 5Hz the LED kind of blinks.
Switching at 1KHz the LED appears steady in color.
OUTA selects the color and F selects the flash rate.
In this case there are 7 different color & blink combinations, there can be more.

Have fun!

Duane J