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projects:esp [2015/02/04 20:29] – [PCF8591] darronprojects:esp [2017/01/12 22:44] (current) – external edit 127.0.0.1
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 The three devices are a Microchip MCP23016 digital I/O expander, NXP PCF8591 ADC/DAC and Microchip 24LC512 EEPROM. The three devices are a Microchip MCP23016 digital I/O expander, NXP PCF8591 ADC/DAC and Microchip 24LC512 EEPROM.
  
-These were chosen because they add useful capabilities to the ESP-01 or RPi and all three are available in DIP format from CPC in the United Kingdom.+These were chosen because they add useful interfacing and logging capabilities to the ESP-01 or RPi and all three are available in DIP format from CPC in the United Kingdom.
  
 +You may also consider adding an I2C RTC to this project and perhaps it shall be updated to include one at a later time.
 === Schematic === === Schematic ===
  
-The circuit is expected to be used with either an ESP-01 attached and with it'UART connected to a computer to load in scripts, else without an ESP-01 and with the I2C lines connected to a Raspberry Pi.+The circuit is expected to be used with either an ESP-01 attached and with its UART connected to a computer to load in scripts, else without an ESP-01 and with the I2C lines connected to a Raspberry Pi.
  
 {{:projects:esp.png?200}} {{:projects:esp.png?200}}
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 === I2C bus === === I2C bus ===
  
-The I2C bus is simple affair with only two lines required for it'operation. This is perfect for the ESP-01 module which only has two GPIOs exposed on it'header pins. For the Raspberry Pi, there are two I2C buses, but only one is normally available.+The I2C bus is simple affair with only two lines required for its operation. This is perfect for the ESP-01 module which only has two GPIOs exposed on its header pins. For the Raspberry Pi, there are two I2C buses, but only one is normally available.
  
 ^Address ^Device | ^Address ^Device |
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 </code> </code>
  
-When the script is run with eSPY we can see the DAC output ramp up and a running commentary.+When the script is run with eSPY we can see the DAC output ramp up with a running status.
 <code> <code>
 0 0
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 I2C EEPROMs have varied addressing schemes. The simplest is a 8-bit address offset, another one where a block selection is made with an I2C address and a byte selection is made with an 8-bit address offset. Yet another, where the I2C address is fixed but it now has a 16-bit address offset and lastly one with both of the last methods combined. I2C EEPROMs have varied addressing schemes. The simplest is a 8-bit address offset, another one where a block selection is made with an I2C address and a byte selection is made with an 8-bit address offset. Yet another, where the I2C address is fixed but it now has a 16-bit address offset and lastly one with both of the last methods combined.
  
-The 24LC512 which uses 16-bit addressing. The addressing byte order is high byte, low byte.+The 24LC512 looked at here uses a fixed I2C address and 16-bit addressing. The addressing byte order is high byte, low byte.
  
 == ESP-01 NodeMcu == == ESP-01 NodeMcu ==
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 238 238
 </code> </code>
- 
-eSPY is still being developed and as yet doesn't filter the LUA prompts from the output. 
  
 == RPi == == RPi ==
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 [[http://www.nxp.com/documents/data_sheet/PCF8591.pdf|PCF8591 data-sheet]]\\ [[http://www.nxp.com/documents/data_sheet/PCF8591.pdf|PCF8591 data-sheet]]\\
 [[http://ww1.microchip.com/downloads/en/DeviceDoc/21754M.pdf|24LC512 data-sheet]]\\ [[http://ww1.microchip.com/downloads/en/DeviceDoc/21754M.pdf|24LC512 data-sheet]]\\
 +