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--- soil_moisture_meter [2014/11/06 15:51] – created breaker27
+++ soil_moisture_meter [2015/01/29 22:43] (current) – [Partlist (in buildup order)] breaker27
@@ Line 14: / Line 14: @@
 |    1     | Transceiver PCB RFM12B                  | IC2        |  {{ parts:ic_rfm12b.jpg }}                   |
 |    1     | IC 74HC14D                              | IC3        |  {{ parts:ic_smd_74hc14d.jpg }}              |
-|    1     | Connector AVR Mini ISP 6pin             | JP1        |  {{ parts:connector_isp.jpg }}               |
+|    1     | Connector AVR Mini ISP 6pin             | JP1        |  {{ parts:connector_mini_isp.jpg }}               |
 |    1     | Connector pin header (for serial TX debugging etc.)  | JP3   |  {{ parts:connector_pinheader.jpg }}  |
 |    1     | Antenna (82,2mm wire)                   | ANT        |  {{ parts:antenna.jpg }}                     |
 |    1     | LED 2mA                                 | LED1       |  {{ parts:led_yellow.jpg }}                  |
-|    1     | Resistor 220R                           | R1, R6     |  {{ parts:resistor_smd_603.jpg }}            |
+|    1     | Resistor 560R                           | R1         |  {{ parts:resistor_smd_603.jpg }}            |
-|    1     | Resistor 1M                             | R4         |  {{ parts:resistor_smd_603.jpg }}            |
+|    1     | Resistor 1M                             | R2         |  {{ parts:resistor_smd_603.jpg }}            |
-|    1     | Resistor 100k                           | R5         |  {{ parts:resistor_smd_603.jpg }}            |
+|    1     | Resistor 100k                           | R3         |  {{ parts:resistor_smd_603.jpg }}            |
-|    1     | Switch                                  | S1         |  {{ parts:switch.jpg }}                      |
+|    1     | Button                                  | S1         |  {{ parts:button.jpg }}                      |
 ===== Buildup of PCB =====
@@ Line 29: / Line 28: @@
   - The first step is to solder (with soldering paste) all the SMD components, which is everything except the RFM12B module, the two pin connectors, LED and antenna.
   - Measure with a continuity checker if there are any short circuits and remove them carefully. Especially check the pins of the ATMega.
-  - Solder the ISP connector and debug TX pin.
+  - Solder the LED and ISP connector.
-  - You should flash the device now and see if everything works.
+  - Flash the device.
-  - Measuring of the idle power consumption is helpful to make sure there are no high impedance short circuits somewhere. (Note: Firmware has to be changed to allow that without connected RFM module.)
+  - Now connect a multimeter to **check the power consumption**. Press the button when the device starts up. The device will blink some seconds very fast and then go to power down mode. **The device should draw only ~0.1µA.** If the current is much higher, you may have a short circuit somewhere.
-  - Solder the RFM12B, LED and antenna with a soldering iron as usual.
+  - Solder the debug TX pin, the RFM12B module and antenna with a soldering iron as usual.
+  - Switch on the device and check power consumption again. With connected RFM12, it should now be ~1.7µA.
 {{https://raw.github.com/breaker27/smarthomatic/develop/hardware/soil_moisture_meter/placing.png?500}}