Differences

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--- power_switch [2014/01/12 19:00] – breaker27
+++ power_switch [2015/11/15 20:57] – [Modification of RFM12 power pin (PCB < V1.1)] breaker27
@@ Line 3: / Line 3: @@
 ===== Needed Parts and PCB =====
-You need a **PCB**. You may use the layout from [[https://github.com/breaker27/smarthomatic/tree/develop/hardware/power_switch_1|Github]] and etch it yourself or [[https://www.smarthomatic.com/shop/|order]] the PCB or a complete kit.
+You need a **PCB**. You may use the layout from [[https://github.com/breaker27/smarthomatic/tree/develop/hardware/power_switch_1|Github]] and etch it yourself or [[https://www.smarthomatic.org/shop/|order]] the PCB or a complete kit.
 ==== Partlist (in buildup order) ====
@@ Line 20: / Line 20: @@
 |    1     | Connector 1 pin header (for serial TX debugging)  | JP5        |  {{ parts:connector_pinheader.jpg }}   |
 |    1     | Capacitor 10µF                          | C1         |  {{ parts:capacitor_10uf.jpg }}        |
+|    1     | Capacitor 1µF                           | C2         |  {{ parts:capacitor_220nf.jpg }}       |
 |    1     | IC ATMega328                            | IC1        |  {{ parts:atmega.jpg }}                |
 |    1     | Relay FTR-K1C (230V, 16A)               | K1         |  {{ parts:relay_ftr_k1c.jpg }}         |
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   * **ATMega:** Before inserting it, you may want to check the voltage levels when switching the power on. Pin7 should have VCC (3V) against pin8 (ground). If you have different voltages: don't panic, nothing is broken, nothing is fried. Search your error. To insert the ATMega, bend the pins at 90 degreed by placing the ATMega on the table and bending it carefully. Then insert it into the IC holder. Be sure that you are not charged with electricity (ESD!) when touching the IC pins.
   * **RFM12B:** You should also check the voltages first before soldering the module. At the place for the radio module the pad beside the antenna and at the opposite side the third pad should read about 3.3 V. For soldering, read [[rfm12b_soldering|the RFM12B mounting instructions]].
+  * **Relais:** If you want to switch high currents, especially at high voltages, it is recommended to solder the wires directly to the relais pins on the bottom of the PCB.
 {{https://raw.github.com/breaker27/smarthomatic/develop/hardware/power_switch_1/placing.png?500}}
@@ Line 55: / Line 57: @@
 describe it...
+===== Modification of RFM12 power pin (PCB < V1.1) =====
+In PCBs >= V1.1, the RFM12 power pin is connected to an ATMega I/O pin to make it possible to restart the transceiver if communication fails.
+If you want to modify your old PCB version to have this feature as well, cut two traces carefully (marked red in the picture) and connect two pins of the RFM transceiver to the ATMega (marked green in the picture).
+{{:powerswitch_v1_mod.jpg?500|}}