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--- pm:prj2026:jan.vaduva:bogdan.olariu [2026/05/12 01:23]
bogdan.olariu
+++ pm:prj2026:jan.vaduva:bogdan.olariu [2026/05/14 05:16] (current)
bogdan.olariu
@@ Line 28: / Line 28: @@
   * Whenever the receiver is placed in the stand the phone is in settings mode, when the user can change the ringtone, add new phone numbers into memory or call saved numbers, all using the disc for selection
-  * When the receiver is taken away from the stand the user can select a number to be called using the disc. The arduino will read the disc signals, will construct the number in a string and the pass it via USART to the SIM800L module using the AT command for calling (ATD+number). If the reciever is placed in the stand during the call, the arduino will send the hang up command (ATH)
+  * When the receiver is taken away from the stand the user can select a number to be called using the disc. The arduino will read the disc signals, will construct the number in a string and then pass it via USART to the SIM800L module using the AT command for calling (ATD+number). If the reciever is placed in the stand during the call, the arduino will send the hang up command (ATH)
   * When a call is incoming, the RING line from the SIM800L will be set LOW, indicating to the arduino that someone is calling. The arduino will then ring the bells using an electromagnet powered by the MOSFET module, acording to the current ringtone
@@ Line 38: / Line 38: @@
 ===== Hardware Design =====
-  * Components
+**Components**
 ^ Component ^ Role ^ Quantity ^
@@ Line 50: / Line 50: @@
 | Electret microphone | Record the voice of the user | 1 |
 | 1N4007 diode | Stop the reverse voltage from the elctromagnet | 1 |
+| Perfboard | Base used to solder the components | 2 |
-  * scheme electrice (se pot lua şi de pe Internet şi din datasheet-uri, e.g. http://www.captain.at/electronic-atmega16-mmc-schematic.png)
+**Schematic**
-  * diagrame de semnal
-  * rezultatele simulării
+{{:pm:prj2026:jan.vaduva:schematic_retro-comm_2026-05-14.png?700|}}
+**Pins used / connections**
+  * The rotary disc encoder is connected to pins PD1 and PD0 in order to use the INT0 and INT1 interrupts to detect the short pulses genrated by the disc for each digit
+  * The PWM of the MOSFET module is connected to PB6, a pin capable of generating the PWM signal necessary for the ringtone
+  * The receiver stand, which will basically act just like a button, will be detected from PB5 using a debouncing method
+  * The RX0 is connected to the TX pin of the SIM800L and the TX0 pin to the RX one of the sim module via a voltage divider
+**Current status**
+  * I have managed to initiate and receive phone calls using the module. I have connected the old speaker of the phone to the sim module and it seems to work fine. I have also tested the audio with an electret microphone and it works. This means that the most important part of the hardware stage is working
+  * I still need to find a good way to place the micropone in the phone receiver and deal with the common ground layout used in the telephone in order to be able to use both speaker and microphone togheter
+  * I have found the connections responsible to detect whether or not the receiver is placed in its stand and will connect them to the arduino. Similarly with the rotary encoder
+  * Here is a picture of the mess:
+{{:pm:prj2026:jan.vaduva:rotary_phone.jpeg?600|}}
+  * For a proof of the working phone calls I have attached a video on the Moodle assignment Milestone 2 (Hardware)
 ===== Software Design =====