BOM.csv

@@ -1,13 +0,0 @@
-Quantity,Manufacture Part Number,Manufacturer,Description,LCSC Part Number,Package
-1,STM32F103C8,STM,Microcontroller ,,
-1,SMD-5032_4P8M20pf20ppm,Zhejang Abel Elec,8Mhz Crystal,C133333,SMD-5032
-1,DC-470-2.1GP,GANGYUAN,GANGYUAN DC-470-2.1GP ,C194407,
-6,XKB5858-W-TP,XKB Enterprise,XKB Enterprise XKB5858-W-TP ,C381091,
-4,WF06Q1002BTL,Walsn Tech Corp,10k 0603 Resistor,C305259,SMD0603
-2,EWH1HM4R7D11OT,Aihua Group,4u7 leaded cap ,C105327,radial_D5P2
-2,ECSS05072R2M101P00,Guangdong TOPAZ Elec Tech,2u2 leaded cap,C156723,radial_D5P2
-12,PE105J2A0501,KYET,1u Polyester film cap,C390180,rectangular_7x5P5
-2,0603CG200J201NT,Guangdong Fenghua Advanced Tech,20pF crystal cap,C63680,SMD0603
-2,0603X106K160NT,Guangdong Fenghua Advanced Tech,10u cap,C70225,SMD0603
-7,D-G080508G1-KS2,Wuxi ARK Tech Elec,LED bright green,C107402,SMD0805
-1,TSA061G50-250,BRIGHT,switch ,C294501,THT

README.md

@@ -1,32 +1,27 @@
-![render image](doc/images/render.png)
+## Wat
 
-<iframe src="https://myhub.autodesk360.com/ue28af833/shares/public/SH56a43QTfd62c1cd96847154d5ed1f7a373?mode=embed" width="640" height="480" allowfullscreen="true" webkitallowfullscreen="true" mozallowfullscreen="true"  frameborder="0"></iframe>
+This pcb is an audio multiplexer, meaning it can switch three analog inputs into one analog output. 
 
-This project contains all design files for a **6:1 audio multiplexer** , meaning it can switch six analog inputs into one analog output. 
+## Why
 
-It is based on the [BD3491](https://www.digikey.de/product-detail/de/rohm-semiconductor/BD3491FS-E2/BD3491FS-E2TR-ND/5720882) which does everthing related to the Audio signals.
+Sometimes you just need more inputs. And this is how you do it.
 
-On top of switching the inputs, it is also able to condition the signal. It can 
+## How
 
-- Apply Bass-Boosting and Treble-Boosting (essentially a crappy 3-Point Equalizer)
-- Amplify the input signal by up to 20dB
-- Add attenuation to the individual channels (aka. balance the left and right channel)
+The BD3491 does all the audio switching. It combines one 6 input switch and an equalizer into a simple package. 
+The STM32 configures the BD3491 to switch to the specified inputs based on pressed buttons or software control.
 
-All of these feature of the chip can be activated with the on-board STM32, which can in turn be controlled 
-with either on-board buttons or via it's integrated USB port. One can either use the serial protocol directly 
-or a [GUI written in python](gui/README.md)  
+# serial control Syntax
+Upon connecting the stm32 to a PC using USB it will register itself as a new Serial Port. The following text commands can be issued via said Serial connection (the baudrate is irrelevant): 
 
-The Board can be supplied over said USB port as well (if the primary use-case implies it beeing connected
-to the PC constantly) or by applying power using a 2.1mm Barrel Jack.
+- `C[number]\n` will change the input to the specified channel. The stm32 echo the command as it was understood. e.g: When Sending `C0\n` it will respond `C0\r\n` to acknowledge the channel switched to **Input 1**. When issuing a `C10` there will be no response, since 10 is out of range. *NOTE:* when using the buttons on the PCB to switch the input, the stm will also issue a `C[number]\r\n` over the serial port if it is connected to notify the PCB of the external input change. 
 
-For more details on the pcb, check the [PCB readme](kicad/README.md)
+- `G[number]\n` will activate an input gain of [number] in dB. It will also respond with the closest gain it can do. e.g: `G10` will result in the stm responding `G12\r\n` which means it will add a 12db input boost, which was the closest matching _valid_ input gain value. You can check the datasheet of the BD3491 to find the possible gain values if this peaks your interest :) 
 
-For details on the Serial command syntax and firmware flashing instructions, check the [firmware readme](firmware/README.md)
+- `L[number]\n` or `R[number]\n` will activate an attenuator in either the left or the right channel. [number] is once again in dB. It works much like the `G`-command. Setting [number] to 0 will deactivate the Attenuation.
 
+- `B[number]\n` or `T[number]\n` adds **B**ass or **T**reble gain to the output
 
-# Why
-
-Because ? 
-
-Sometimes you just need more inputs. This is how you do it. 
+- `M[0/1]\n` will either mute or unmute the output
 
+- `S[0/1]\n` will connect all inputs to the output 

firmware/Include/bd3491.h

@@ -20,9 +20,9 @@ int bd_set_gain(I2C_HandleTypeDef * handle, uint8_t gain_in_db);
 uint8_t bd_set_attenuation(I2C_HandleTypeDef * handle, uint8_t right_channel, uint8_t attenuation_in_db);
 
 // when gain == 0, cut bass boost
-uint8_t bd_set_bass_boost(I2C_HandleTypeDef * handle, uint8_t gain);
+void bd_set_bass_boost(I2C_HandleTypeDef * handle, uint8_t gain);
 // when gain == 0, cut treble boost
-uint8_t bd_set_treble_boost(I2C_HandleTypeDef * handle, uint8_t gain);
+void bd_set_treble_boost(I2C_HandleTypeDef * handle, uint8_t gain);
 
 enum BD_SOURROUND_GAIN {
 	BD_SOURROUND_OFF = 0,

firmware/Include/main.h

@@ -37,20 +37,7 @@ extern "C" {
 
 /* Exported types ------------------------------------------------------------*/
 /* USER CODE BEGIN ET */
-struct ui_state {
-  uint8_t oldchannel;
-  enum {
-    UI_STATE_NORMAL = 0, 
-    UI_STATE_MUTE,
-    UI_STATE_SHORT,
-  } state;
 
-  uint8_t gain;
-  uint8_t bboost, tboost;
-  uint8_t latt, ratt;
-};
-
-extern struct ui_state ui_state; // global ui state
 /* USER CODE END ET */
 
 /* Exported constants --------------------------------------------------------*/
@@ -67,12 +54,8 @@ extern struct ui_state ui_state; // global ui state
 void Error_Handler(void);
 
 void set_input(uint8_t channel);
-int get_input();
 void set_attenuation(uint8_t left, uint8_t right);
-void set_mute(uint8_t mute); //< tries to switch to muted ui state
-int is_muted(); //< returns whether the ui is muted
-void set_short(uint8_t shorted); //< tries to switch to shorted ui state
-int is_shorted();
+void set_mute(uint8_t mute);
 
 /* USER CODE BEGIN EFP */
 

firmware/README.md

@@ -1,35 +0,0 @@
-
-# Building the Firmware
-
-In order to build the firmware, [platformio](https://platformio.org/install/cli) must be installed. 
-
-To build the firmware, navigate to this folder using the terminal of your choice and type
-
-```bash
-platformio run
-```
-
-## Flashing the firmware 
-
-If you happen to have an stlink compatible interface (e.g the [programmer attached the nucleo-boards](https://jeelabs.org/book/1547a/])), 
-then (after connecting said interface to the PC and the PCB), 
-the firmware can be flashed with 
-
-```bash
-platformio run -t upload
-```
-
-# serial control Syntax
-Upon connecting the stm32 to a PC using USB it will register itself as a new Serial Port. The following text commands can be issued via said Serial connection (the baudrate is irrelevant): 
-
-- `C[number]\n` will change the input to the specified channel. The stm32 echo the command as it was understood. e.g: When Sending `C0\n` it will respond `C0\r\n` to acknowledge the channel switched to **Input 1**. When issuing a `C10` there will be no response, since 10 is out of range. *NOTE:* when using the buttons on the PCB to switch the input, the stm will also issue a `C[number]\r\n` over the serial port if it is connected to notify the PCB of the external input change. 
-
-- `G[number]\n` will activate an input gain of [number] in dB. It will also respond with the closest gain it can do. e.g: `G10` will result in the stm responding `G12\r\n` which means it will add a 12db input boost, which was the closest matching _valid_ input gain value. You can check the datasheet of the BD3491 to find the possible gain values if this peaks your interest :) 
-
-- `L[number]\n` or `R[number]\n` will activate an attenuator in either the left or the right channel. [number] is once again in dB. It works much like the `G`-command. Setting [number] to 0 will deactivate the Attenuation.
-
-- `B[number]\n` or `T[number]\n` adds **B**ass or **T**reble gain to the output
-
-- `M[0/1]\n` will either mute or unmute the output
-
-- `S[0/1]\n` will connect all inputs to the output 

firmware/Src/bd3491.c

@@ -64,30 +64,19 @@ int bd_set_gain(I2C_HandleTypeDef * handle, uint8_t gain_in_db) {
 uint8_t bd_set_attenuation(I2C_HandleTypeDef * handle, uint8_t right_channel, uint8_t attenuation_in_db) {
 	if ((attenuation_in_db&0x7F) > 87)
 		attenuation_in_db = BD_INF_ATTENUATION;
-	
-	if (right_channel) 
-		right_channel = 1;
-	
-	bd_write_reg(handle, 0x22 - right_channel, attenuation_in_db | 0x80);
+
+	bd_write_reg(handle, 0x21 + right_channel, attenuation_in_db | 0x80);
 	return attenuation_in_db;
 }
 
 // when gain == 0, cut bass boost
-uint8_t bd_set_bass_boost(I2C_HandleTypeDef * handle, uint8_t gain) {
-	if (gain > 0x07) gain = 0x07;
-
+void bd_set_bass_boost(I2C_HandleTypeDef * handle, uint8_t gain) {
 	bd_write_reg(handle, 0x51, (gain == 0)?(0x80):(0x00) | (gain&0x07) << 1);
-
-	return gain;
 }
 
 // when gain == 0, cut treble boost
-uint8_t bd_set_treble_boost(I2C_HandleTypeDef * handle, uint8_t gain) {
-	if (gain > 0x07) gain = 0x07;
-
+void bd_set_treble_boost(I2C_HandleTypeDef * handle, uint8_t gain) {
 	bd_write_reg(handle, 0x57, (gain == 0)?(0x80):(0x00) | (gain&0x07) << 1);
-
-	return gain;
 }
 
 void bd_set_sourround(I2C_HandleTypeDef * handle, enum BD_SOURROUND_GAIN gain) {

firmware/Src/main.c

@@ -102,92 +102,58 @@ int test_button_pressed() {
 #undef TEST_BUTTON
 }
 
-struct ui_state ui_state = {
+struct ui_state {
+  uint8_t oldchannel;
+  uint8_t mute;
+} ui_state = {
   .oldchannel = -1,
-  .state = UI_STATE_NORMAL,
+  .mute = 0,
 };
 
 void set_input(uint8_t channel) {
-	if (ui_state.state != UI_STATE_NORMAL || ui_state.oldchannel == channel || channel >= 6)
+	if (ui_state.oldchannel == channel || channel >= 6)
 		return;
 
-  set_input_led(ui_state.oldchannel, 0);	
-  
-  set_input_led(channel, 1);
+	set_input_led(ui_state.oldchannel, 0);
 
-  // invert bd inputs to match the numbers on the case
-  bd_set_input(&hi2c1, 5-channel);
+  // do not disturb the mute mode
+  if (!ui_state.mute)
+  {
+	  set_input_led(channel, 1);
+
+	  // invert bd inputs to match the numbers on the case
+    bd_set_input(&hi2c1, 5-channel);
+  }
 
 	ui_state.oldchannel = channel;
 
 	printf("C%d\n", channel);
 }
 
-int get_input() {
-  return ui_state.oldchannel;
-}
-
-// only mute if the ui allows to 
 void set_mute(uint8_t mute) {
-  if(UI_STATE_MUTE == ui_state.state && mute)
-    // no state change required
+  if(ui_state.mute == mute)
     return;
 
-  // figure out the state transition  
-  if (UI_STATE_NORMAL == ui_state.state && mute) {
-    ui_state.state = UI_STATE_MUTE;
-    HAL_GPIO_WritePin(USER_LED_GPIO_Port, USER_LED_Pin, 1);
-    set_input_led(ui_state.oldchannel, 0);
-    bd_set_input(&hi2c1, BD_INPUT_MUTE);
-  } 
-  else if (UI_STATE_MUTE == ui_state.state && !mute) 
-  {
-    ui_state.state = UI_STATE_NORMAL;
+  if (0 == (ui_state.mute = mute)) {
     // hack to make reactivation of the last channel easier
     uint8_t old_input = ui_state.oldchannel;
     ui_state.oldchannel = -1;
 
     set_input(old_input);
-    HAL_GPIO_WritePin(USER_LED_GPIO_Port, USER_LED_Pin, 0); 
+    HAL_GPIO_WritePin(USER_LED_GPIO_Port, USER_LED_Pin, 0);
   }
-}
-
-int is_muted() {
-  return ui_state.state == UI_STATE_MUTE;
-}
-
-void set_short(uint8_t do_short) {
-  // test for possible state changes
-  if (UI_STATE_NORMAL == ui_state.state && do_short) 
-  {
-    ui_state.state = UI_STATE_SHORT;
-    bd_set_input(&hi2c1, BD_INPUT_ALL);
-
-    // visualize that all inputs are shorted
-    for (int i = 0; i < 6; ++i) 
-      set_input_led(i, 1);
-  } 
-  else if (UI_STATE_SHORT == ui_state.state && !do_short) 
-  {
-    ui_state.state = UI_STATE_NORMAL;
-    
-    for (int i = 0; i < 6; ++i) 
-      set_input_led(i, 0);
-
-    // reactivate currently selected input
-    uint8_t old_input = ui_state.oldchannel;
-    ui_state.oldchannel = -1;
-    set_input(old_input);
+  else {
+    HAL_GPIO_WritePin(USER_LED_GPIO_Port, USER_LED_Pin, 1);
+    set_input_led(ui_state.oldchannel, 0);
+    bd_set_input(&hi2c1, BD_INPUT_MUTE);
   }
-}
 
-int is_shorted() {
-  return ui_state.state == UI_STATE_SHORT;
+  printf("M%d\n", ui_state.mute?1:0);
 }
 
 void set_attenuation(uint8_t left, uint8_t right) {
-	ui_state.latt = bd_set_attenuation(&hi2c1, 0, left);
-  ui_state.ratt = bd_set_attenuation(&hi2c1, 1, right);
+	bd_set_attenuation(&hi2c1, 0, left);
+	bd_set_attenuation(&hi2c1, 1, right);
 }
 
 
@@ -236,7 +202,6 @@ int main(void)
   set_attenuation(0,0);
   int count = 0;
   int button_timeout = 0;
-  
   /* USER CODE END 2 */
 
   /* Infinite loop */
@@ -261,8 +226,7 @@ int main(void)
 
       if (1000 < button_timeout) {
         // long press, toggle mute
-        set_mute(!is_muted());
-        printf("M%d\n", is_muted());
+        set_mute(!ui_state.mute);
         button_timeout = 0;
       }
 

firmware/Src/message_parser.c

@@ -138,24 +138,16 @@ int parse_buffer() {
 			uint16_t gain;
 			if (next_arg_unsigned(&gain)) break;
 
-			printf("G%d\n", (ui_state.gain = bd_set_gain(&hi2c1, gain)));
+			printf("G%d\n", bd_set_gain(&hi2c1, gain));
 		}
 		break;
 	case 'L':
 	case 'R':
 	{
 		uint16_t att;
-		uint8_t dir = 0;
-		uint8_t * save = &ui_state.latt;
-
 		if (next_arg_unsigned(&att)) break;
-		
-		if (temp == 'R') {
-			dir = 1;
-			save = &ui_state.ratt;
-		}
 
-		printf("%c%d\n", temp, (*save = bd_set_attenuation(&hi2c1, dir, att&0xFF)));
+		printf("%c%d\n", temp, bd_set_attenuation(&hi2c1, temp == 'R', att&0xFF));
 	}
 		break;
 	case 'M':
@@ -164,46 +156,11 @@ int parse_buffer() {
 		if (next_arg_unsigned(&mute)) break;
 		
 		set_mute(mute);
-		printf("M%d\n", is_muted());
-	}
-		break;
-	case 'S':
-	{
-		uint16_t shorted;
-		if (next_arg_unsigned(&shorted)) break;
-		
-		set_short(shorted);
-		printf("S%d\n", is_shorted());
 	}
 		break;
 	case 'B':
-	{
-		uint16_t boost;
-		if (next_arg_unsigned(&boost)) break;
-
-		printf("B%d\n", (ui_state.bboost = bd_set_bass_boost(&hi2c1, boost)));
-	}
-		break;
 	case 'T':
-	{
-		uint16_t boost;
-		if (next_arg_unsigned(&boost)) break;
 
-		printf("T%d\n", (ui_state.tboost = bd_set_treble_boost(&hi2c1, boost)));
-	}
-		break;
-	case '?':
-	{
-		// return the system state
-		printf("M%d\n", is_muted());
-		printf("S%d\n", is_shorted());
-		printf("C%d\n", get_input());
-		printf("B%d\n", ui_state.bboost);
-		printf("T%d\n", ui_state.tboost);
-		printf("L%d\n", ui_state.latt);
-		printf("R%d\n", ui_state.ratt);
-	}
-		break;
 	default:
 		printf("E\n");
 	}

gui/.vscode/settings.json

@@ -1,3 +0,0 @@
-{
-    "python.pythonPath": "/usr/bin/python"
-}

gui/app.spec

@@ -1,33 +0,0 @@
-# -*- mode: python ; coding: utf-8 -*-
-
-block_cipher = None
-
-
-a = Analysis(['app.py'],
-             pathex=['/home/julian/git/audioMux/gui'],
-             binaries=[],
-             datas=[],
-             hiddenimports=[],
-             hookspath=[],
-             runtime_hooks=[],
-             excludes=[],
-             win_no_prefer_redirects=False,
-             win_private_assemblies=False,
-             cipher=block_cipher,
-             noarchive=False)
-pyz = PYZ(a.pure, a.zipped_data,
-             cipher=block_cipher)
-exe = EXE(pyz,
-          a.scripts,
-          a.binaries,
-          a.zipfiles,
-          a.datas,
-          [],
-          name='app',
-          debug=False,
-          bootloader_ignore_signals=False,
-          strip=False,
-          upx=True,
-          upx_exclude=[],
-          runtime_tmpdir=None,
-          console=False )

gui/icon.svg

@@ -1,77 +0,0 @@
-<?xml version="1.0" encoding="UTF-8" standalone="no"?>
-<!-- Created with Inkscape (http://www.inkscape.org/) -->
-
-<svg
-   xmlns:dc="http://purl.org/dc/elements/1.1/"
-   xmlns:cc="http://creativecommons.org/ns#"
-   xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
-   xmlns:svg="http://www.w3.org/2000/svg"
-   xmlns="http://www.w3.org/2000/svg"
-   xmlns:sodipodi="http://sodipodi.sourceforge.net/DTD/sodipodi-0.dtd"
-   xmlns:inkscape="http://www.inkscape.org/namespaces/inkscape"
-   width="10mm"
-   height="10mm"
-   viewBox="0 0 10 10"
-   version="1.1"
-   id="svg8"
-   inkscape:version="0.92.4 5da689c313, 2019-01-14"
-   sodipodi:docname="icon.svg"
-   inkscape:export-filename="/home/julian/git/audioMux/gui/icon/1.png"
-   inkscape:export-xdpi="325.12"
-   inkscape:export-ydpi="325.12">
-  <defs
-     id="defs2" />
-  <sodipodi:namedview
-     id="base"
-     pagecolor="#ffffff"
-     bordercolor="#666666"
-     borderopacity="1.0"
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-     inkscape:pageshadow="2"
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-     inkscape:current-layer="layer1"
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-     inkscape:window-height="1058"
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-     inkscape:window-y="20"
-     inkscape:window-maximized="1" />
-  <metadata
-     id="metadata5">
-    <rdf:RDF>
-      <cc:Work
-         rdf:about="">
-        <dc:format>image/svg+xml</dc:format>
-        <dc:type
-           rdf:resource="http://purl.org/dc/dcmitype/StillImage" />
-        <dc:title />
-      </cc:Work>
-    </rdf:RDF>
-  </metadata>
-  <g
-     inkscape:label="Ebene 1"
-     inkscape:groupmode="layer"
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gui/tray.py

@@ -1,55 +0,0 @@
-import wx
-from wx import adv
-
-def create_menu_item(menu, label, func):
-    item = wx.MenuItem(menu, -1, label)
-    menu.Bind(wx.EVT_MENU, func, id=item.GetId())
-    menu.AppendItem(item)
-    return item
-
-
-class Tray(wx.adv.TaskBarIcon):
-    def __init__(self, parent):
-        super().__init__()
-        self.Bind(wx.adv.EVT_TASKBAR_LEFT_DOWN, self.OnLeftDown)
-        self.SetIcon(wx.Icon("icon/1.png"))
-        self.parent = parent
-
-    def CreatePopupMenu(self):
-        menu = wx.Menu()
-        hidem = wx.MenuItem(menu, wx.ID_ANY, 'Show Window')
-        menu.Bind(wx.EVT_MENU, self.ShowParent, id=hidem.GetId())
-        menu.Append(hidem)
-        menu.AppendSeparator()
-        
-        quitm = wx.MenuItem(menu, wx.ID_ANY, 'Quit')
-        menu.Bind(wx.EVT_MENU, self.OnExit, id=quitm.GetId())
-        menu.Append(quitm)
-        return menu
-
-    def CreateSelectionMenu(self):
-        return None
-
-    def OnLeftDown(self, event):
-        menu = self.CreateSelectionMenu()
-        if menu:
-            self.PopupMenu(menu)
-        
-  
-    def OnExit(self, event):
-        # close self and parent
-        wx.CallAfter(self.Destroy)
-        wx.CallAfter(self.parent.Destroy)
-
-    def ShowParent(self, evt):
-        self.parent.Show()
-
-if __name__ == "__main__":
-    app = wx.App()
-
-    
-    # create an empty frame to keep the main loop running
-    Tray(wx.Frame(None))
-    
-    app.MainLoop()
-    

kicad/README.md

@@ -1,29 +0,0 @@
-![THE PCB](../doc/audioMux-brd.svg)
-
-There are a total of six solderjumpers on the board:
-
-# switching to the barrel jack as voltage supply
-
-*JP3* and *JP4* set the source for the supply voltage. 
-*JP4* connects the voltage input to the barrel jack, *JP4* connects it to the USB +5V rail.
-
-Per Default JP4 is closed and JP3 is open, making the default way of supplying voltage the USB jack. 
-
-If the Barrel Jack should be used, then **JP4 has to be opened first** by cutting the trace which shorts it by default, otherwise **the USB voltage will be shorted with the barrel jack, causing potential damage to the USB port**.
-Afterwards, *JP3* can be closed with a small blob of solder. 
-
-# activating the equalizer
-
-*JP1* and *JP2* connect the output of the Audio switching part of the Rohm chip. 
-When left in the default setting, they will connect them to the output jack directly, bypassing the Equalisation part of the chip completely.
-
-By selecting the other possible path, the equalisation circuit becomes usable. For this to work, 
-*JP7* and *JP8* have to be closed with small solder blobs as well, since those connect the equalizers 
-output to the output audio jack.
-
-# Assembling the rest 
-
-For assembly of the board, check the [documentation folder](../doc). It contains the [interactive bill of materials](../doc/interactive_placement.html),
-which indicates what components go where.
-
-Also take a look at the [BOM](../doc/BOM.xlsx) for what components can be sourced where.