Update README.md

README.md

@@ -4,9 +4,7 @@
 
 [TEA5767](https://www.sparkfun.com/datasheets/Wireless/General/TEA5767.pdf) is a cheap but functional FM radio module, which allow you to build DIY FM radios. It comes with an antenna via a 3.5mm jack but have no internal volume control. 
 
-This driver has been tested on ESP8266, ESP32 and RPi Pico running MicroPython v1.16.
-
-The CircuitPython version can be found [here](https://github.com/alankrantas/circuitpython-TEA5767).
+This driver has been tested on ESP8266, ESP32 and RPi Pico running MicroPython v1.16. The **CircuitPython** version can be found [here](https://github.com/alankrantas/circuitpython-TEA5767).
 
 ## Wiring
 
@@ -21,49 +19,60 @@ Both 3.3V and 5V power works; 5V may results better sound quality.
 
 ## Import and Initialize
 
-To import and initialize the module:
+Upload ```TEA5767.py``` to your board. You can use [Thonny](https://randomnerdtutorials.com/getting-started-thonny-micropython-python-ide-esp32-esp8266/) to do so.
+
+To import and initialize the driver:
 
 ```python
 from machine import Pin, SoftI2C
 from TEA5767 import Radio
 
 i2c = SoftI2C(scl=Pin(5), sda=Pin(4), freq=400000)
 radio = Radio(i2c)  # initialize and set to the lowest frequency
-radio = Radio(i2c, freq=99.7)  # initialize and set to a specific frequency
+radio = Radio(i2c, freq=106.7)  # initialize and set to a specific frequency
 
 print('Frequency: FM {}\nReady: {}\nStereo: {}\nADC level: {}'.format(
         radio.frequency, radio.is_ready,  radio.is_stereo, radio.signal_adc_level
         ))
 ```
 
-You can use ```I2C``` module on pins that supported hardware I2C bus.
+You can also use ```I2C``` module on pins that supported hardware I2C bus (ESP8266s dno't have them):
+
+```python
+from machine import Pin, I2C
+from TEA5767 import Radio
+
+# Hardware I2C bus 0 on ESP32
+i2c = I2C(0, scl=Pin(18), sda=Pin(19), freq=400000)
+radio = Radio(i2c)
+```
 
 ## Parameters
 
-There are a list of parameters that you can set for the radio:
+The radio can be initialized with the following parameters:
 
 ```python
-radio = Radio(i2c, addr=0x60, freq=99.7, band="US", stereo=True,
+radio = Radio(i2c, addr=0x60, freq=106.7, band="US", stereo=True,
                       soft_mute=True, noise_cancel=True, high_cut=True)
 ```
 
 | Parameter | description |
 | --- | --- |
-| i2c | machine.I2C or machine.SoftI2C object |
-| addr | I2C address (default 0x60) |
-| freq | FM frequency (default = lowest freq by the band setting) |
-| band | band limits; "US" (default) = US/Europe band (87.5-108 MHz); "JP" = Japan band (76-91 MHz) |
-| stereo | stereo mode (default True = use stereo sound if possible; False = forced mono) |
-| soft_mute | soft mute mode (noise control, default True) |
-| noise_cancel | stereo noise cancelling (default True) |
-| high_cut | high cut control (noise control, default True) |
+| ```i2c``` | ```machine.I2C``` or ```machine.SoftI2C``` object |
+| ```addr``` | I2C address (default ```0x60```) |
+| ```freq``` | FM frequency (default = lowest freq by the ```band``` setting) |
+| ```band``` | band limits; ```"US"``` (default) = US/Europe band (87.5-108 MHz); ```"JP"``` = Japan band (76-91 MHz) |
+| ```stereo``` | stereo mode (default ```True``` = use stereo audio if possible; ```False``` = forced mono) |
+| ```soft_mute``` | soft mute mode (noise control, default ```True```) |
+| ```noise_cancel``` | stereo noise cancelling (default ```True```) |
+| ```high_cut``` | high cut control (noise control, default ```True```) |
 
 ## Set Frequency
 
 Set the radio to a specific frequency:
 
 ```python
-radio.set_frequency(99.7)  # set to FM 99.7
+radio.set_frequency(106.7)  # set to FM 106.7
 ```
 
 ## Change Frequency
@@ -75,51 +84,51 @@ radio.change_freqency(-0.1)  # decrease 0.1 MHz
 
 These methods also will change the direction of search mode (see below).
 
-## Search Mode
+## Mute/standby Mode
 
 ```python
-radio.search(True)  # turn on search mode
-radio.search(False)  # turn off search mode
-radio.search(not radio.search_mode)  # toogle search mode
-radio.search(True, dir=1, adc=7)  # turn on search mode and set search parameters
+radio.mute(True)
+radio.standby(True)
 ```
 
-If the search mode is enabled, the radio would attempt to find a station with strong signal whenever you set a new frequency.
-
-* dir = search direction; 1 = search upward along frequency (default), 0 = downward.
-* adc = desired signal ADC resolution (sound quality), default 7. Can be set as 0, 5, 7 or 10. The radio would try to find a station which ADC level satisfied this setting.
+```radio.mute()``` is simply turning off the sound output. If you want to save power, use ```radio.standby()``` instead.
 
-The radio might need some time to find a new station.
+The TEA5767 also allows you to turn off right and/or left speaker, but I decided not to implement these functions.
 
-## Mute/standby Mode
+## Search Mode
 
 ```python
-radio.mute(True)
-radio.standby(True)
+radio.search(True)  # turn on search mode
+radio.search(False)  # turn off search mode
+radio.search(not radio.search_mode)  # toogle search mode
+radio.search(True, dir=1, adc=7)  # turn on search mode and set search parameters
 ```
 
-```radio.mute()``` is simply turning off the sound output. If you want to save power, use ```radio.standby()``` instead.
+* ```dir``` = search direction; ```1``` = search station by increasing frequency (default), ```0``` = decreasing.
+* ```adc``` = desired signal ADC resolution (sound quality). Available values are ```0```, ```5```, ```7``` (default) or ```10```. The radio would try to find a station which ADC level satisfied this setting.
 
-The TEA5767 also allows you to turn off right and/or left speaker, but I decided not to implement these functions.
+When the search mode is enabled, the radio would attempt to find a station with strong signal **whenever you set a new frequency or change it**.
+
+The radio may need a bit of time to tune on a stable signal, so it would be recommended to run ```radio.read()``` and keep updating your external display with ```radio.frequency``` on loop.
 
 ## Read Status From the Radio
 
 Some variables will be updated after calling ```radio.read()```:
 
 ```python
 radio.read()
-my_variable = radio.frequency
-my_variable = radio.search_mode
-my_variable = radio.is_ready
-my_variable = radio.is_stereo
-my_variable = radio.signal_adc_level
+frequency = radio.frequency
+search_mode = radio.search_mode
+is_ready = radio.is_ready
+is_stereo = radio.is_stereo
+signal_adc_level = radio.signal_adc_level
 ```
 
-* radio.frequency: current frequency, float number (may be changed in search mode)
-* radio.search_mode: search mode status (True/False)
-* radio.is_ready: station is ready (signal is strong enough)? (True/False)
-* radio.is_stereo: stereo mode status? (True/False)
-* radio.signal_adc_level: station ADC resolution? (0, 5, 7 or 10)
+* ```radio.frequency```: current frequency, float number (may be changed in search mode)
+* ```radio.search_mode```: search mode status (True/False)
+* ```radio.is_ready```: station is ready (signal is strong enough)? (True/False)
+* ```radio.is_stereo```: stereo mode status? (True/False)
+* ```radio.signal_adc_level```: station ADC resolution? (0, 5, 7 or 10)
 
 You may need to call it a few times with some time delay when the search mode is enabled (the radio frequency would jump around a bit).
 
@@ -129,7 +138,7 @@ You may need to call it a few times with some time delay when the search mode is
 radio.update()
 ```
 
-This method will be automatically called by many other methods of the radio. If you wish to change some parameters, you can manually call ```radio.update()``` to update radio.
+This method will be automatically called by many other methods of the radio. If you wish to change some parameters, you can manually call ```radio.update()``` to update radio status:
 
 ```python
 radio.stereo_mode = True
@@ -138,11 +147,11 @@ radio.high_cut_mode = True
 radio.update()
 ```
 
-By default ```radio.update()``` will wait 50 ms at the end and then call ```radio.read()```.
+By default ```radio.update()``` will wait 1 ms at the end and then call ```radio.read()``` for the I2C bus have maximum delay of 400 us.
 
 ## A Simplified MicroPython Version Without Using This Driver
 
-If you just want to tune the frequency of TEA5767, you can use code as short as below (simply paste it into your script):
+If you just want to set the frequency of TEA5767, you can use code as short as below (simply paste it into your script):
 
 ```python
 from machine import Pin, SoftI2C
@@ -153,7 +162,7 @@ def radio_frequency(freq):
     freqB = 4 * (freq * 1000000 + 225000) / 32768
     i2c.writeto(0x60, bytearray([int(freqB) >> 8, int(freqB) & 0XFF, 0X90, 0X1E, 0X00]))
 
-radio_frequency(99.7)
+radio_frequency(106.7)
 ```
 
-This code does not read anything back and don't use enable search mode, but turn on stereo mode, soft mute, stereo noise cancelling and high cut.
+This code does not read anything back and don't enable the search mode, but will turn on stereo mode, soft mute, stereo noise cancelling and high cut.