Picaxe-based IR Control Module Pair PART NO. 2171014 The IRGEII is an IR (Infra Red) Transmitter and Receiver pair that uses a 38 KHZ frequency of invisible light to communicate simple instructions. The heart of the IRGEII is a small PicAxe micro-controller that both creates the 38Khz transmission and also translates the received signal. The receiver includes a Bi-Color (Red/Green) LED that displays one or the other received codes. It also provides a 2 pin bus that can be used to control anything attached to it. Applications are shown that include a remote control LED light dimmer and a direction of travel remote control for a Parallax Boe-Bot. The transmitter is designed to fit on top of an included 2AAA battery holder and the receiver is powered by the host circuit it is attached to. Time Required: 1 day depending on experience Experience Level: Intermediate Required tools and parts: Soldering Iron Diagonal cutters Fine needle nose pliers DREMEL tool with cutting disc or a fine tooth saw picaxe 08m2 micro controller- robotshop (You will need a programmer) Bill of Materials: Qty Jameco SKU Component Name 1 106526 (TXLD) IR emmiter diode or similar 38khz 1 2109691 (RXLD) IR receiver OR EQUIVALENT 2 51626 (IC1,IC2) ic sockets or similar 2 691180 (R3,R8) 22K 1/4 watt resistor or equivalent 4 691104 (R1,R4,R6,R7) 10K 1/4 watt resistor or equiv 1 161817 (S1) slide switch or equiv footprint 2 155380 (SW1,SW2) Tactile push button switch or equiv footprint 1 334749 (LD1) 3mm blue LED or similar 1 783498 (Q1) NPN transistor or similar NPN 1 179039 (D2) 4.7V Zener Diode or similar 2 2157175 100 ohm 1/4 watt resistor or similar 1 2161043 (R5) 10 ohm 1/4 watt resistor or equiv
1 1995960 (D4,D3) Bi-Color LED or equiv 2 2081334 (J1) 1/8" stereo audio jack or equiv footprint 1 216292 (B1) 2 AAA Battery holder with cover or equiv footprint 1 117560 (H4) 4 pin male header or equiv Step 1 - Separating the Transmitter and Receiver board Grasp board firmly or place on the edge of a counter and snap off the smaller receiver board. If the board does not separate, cut between the lines of the two boards with a dremel or similar saw Step 2 - IRGEII transmitter parts identification Locate the components shown and match them with the transmitter board. Make sure that all the parts are accounted for. You may want to test inserting some of the parts and make sure you understand how they assemble. Step 3 - Mounting the lowest profile parts Identify the resistor values by their color code as shown in FIG.6. Bend the legs as shown in FIG. 7 and solder each resistor into place trimming off the excess leg.
Step 4 - Mounting the InfraRed emitter LED Locate the large clear LED and study the drawing in FIG. 1 that defines what is the Anode and Cathode side of the LED. This LED mounts with the same polarity characteristics of a visible LED. The FLAT side which has the shorter lead is the cathode and will mount matching the flat side outline on the board as shown in FIG. 1. Bend the pins making sure that the bend will allow the LED to mount correctly as shown with the LED end close to the end of the board as shown in the illustration. Step 5 - Mounting the next height profile parts Locate the NPN transistor and insert it into the board matching the outline on the circuit board as shown in FIG. 3. Locate the 0.1 uf capacitor and mount it into the location marked C2 and solder into place. Mount the LED paying close attention to the anode and cathode side of the LED. The negative and shorter cathode leg will mount on the FLAT side of the outline.
Step 6 - Mounting the next height profile parts Mount the Slide switch either direction in the (S1) hole pattern shown in FIG. 9. Locate the 1/8" audio jack and mount it into the hole pattern shown in FIG. 6. Be sure to press the jack firmly into the holes until it is flush with the board and solder into place. If the part is loose in the holes, it may be necessary to place something under it while soldering to keep it flush against the board. Step 7 - Mounting the IC socket and Tactile Switches Locate one of the 8 pin IC sockets and orient the Notch side of the socket to match the outline on the board. Insert the socket and solder it into place making sure that the socket stays flush with the board. You may need to place something under the board to keep the socket in place during solder. Locate the two Tactile switches shown in FIG. 8 and mount them into SW1 and SW2.
Step 8 - Mounting the battery holder Purchase an inexpensive pack of pre-cut or cut to length velcro "Hook and Loop" fasteners. The idea is to add the hook or loop side to the battery holder and the partner for it to the backside of the circuit board. Be sure to trim off as much excess wire or pins from your soldering before attaching to the board. Once the battery pack is fastened to the circuit board as shown in FIG. 3, trim the positive (red) and negative (black) wires on the pack as shown and insert and solder the leads from the BACKSIDE of the board. Normally you put leads into holes from the topside of the board but this will put less strain on the wires and be neater. Make sure the RED lead is placed in the hole with the (+) marking which is closest to the EDGE near the bottom of the board. Step 9 - Locating and Identifying parts for the receiver Locate and identify the parts shown in FIG. 9 If all the parts can be located and properly identified proceed to the next step
Step 10 - Mounting the lowest profile parts Mount the parts shown in FIG. 8 paying close attention to the orientation of the band on the Zener diode by matching it to the band on the board outline Step 11 - Mounting the next height profile parts Locate the 8 pin IC socket and match the notch to the board outline shown in FIG. 4 and solder into place. Mount the Bi-Color LED either direction and solder into place. Mount the 1/8" audio jack as shown in FIG. 7 and solder into place making sure it is flush with the board.mount the receiver as shown in FIG. 3 with the leads toward the top of the board like the outline. Bend the legs at a 90 deg angle and mount the lens in the center of the outline.
Step 12 - Mounting the 4 pin Male header With a pair of fine needle nose pliers, push the plastic holder all the way down to one end as shown in FIG. 6. Place the header into the board with the pins downward leaving the plastic binder on the top of the board. Step 13 - What you will need to program the IRGEII If you have an older computer and it has a DB9 serial port, you can easily build a programming cable as shown in the illustration. If your computer is newer or you have a laptop, more than likely you will need a programming cable.
Step 14 - LED light dimmer example To build the LED dimmer circuit you will need the following extra parts which are all available from Jameco. 1) Prototyping breadboard Jameco part# 20601 2) AD5220 Digital Potentiometer Jameco part# 1777751 3) 100K 1/4 Watt resistor Jameco part# 691340 4) NPN 2n4401 transistor Jameco part# 783498 5) Bright LED Jameco part# 2095189 Yellow or 2095171 Red Step 15 - Part identification for dimmer example The example in FIG. 2 points out that if you purchase the AD5220 as an SOIC, you will also need an SOIC to DIP adapter to be able to use the part in a prototyping board. The part from DigiKey is a PDIP and can be used with the breadboard. The NPN transistor isn't critical and most any NPN will work including 2N3904 and 2N2222.
Step 16 - Assembling the example circuit on a breadboard The power supply for the dimmer circuit is used to power the receiver and is typical of how the receiver is powered. The illustration demonstrates how the male header can be used to control another circuit. In this circuit, the transmitter sends one code to dim the LED. When this happens, the processor holds one pin of the AD5220 low and sends continuous pulses (as long as the transmitter is sending) that adjusts the potentiometer to a higher value dimming the LED. If the other transmit button is pushed, the processor holds the same pin on the AD5220 "High" and sends pulses that adjust the potentiometer to a lower resistive value causing the LED to brighten. The same circuit could easily be modified to dim a much higher current lamp. Step 17 - Basic Source Code for the Transmitter Once you have built the Transmitter and Receiver circuits, you will need to download and program the software for each. This is the BASIC CODE for generic Transmitter operation
Step 18 - Basic Source Code for the Receiver Once you complete the construction of your boards, you will need to download the software and program the receiver. This is the BASIC SOURCE CODE for the receiver circuit. Step 19 - Using the IRGEII to control a Boe-Bot The illustration in FIG. 1 shows how the receiver can plug into the breadboard area on top of a Parallax Boe-Bot robot. In this application, the receiver receives one of two signals. One signal instructs the robot to turn Left. The other signal changes the direction of travel Right. The receiver acts parasitically in deriving power from the Boe-Bot. The breadboard allows the two I/O pins from the male header to connect to the Boe-Bot's shield "female" header with jumpers. This could just as easily be an Arduino it is controlling because of the ability to plug into a breadboard area.