II. Quick Specs comparison¶

ATTiny45¶

Because I use an ATTiny45 in my Echo Hello-World Board, I downloaded the corresponding datasheet from the FabAcademy Page

pinout diagram¶

block diagram¶

available different variants¶

Features¶

And here are some quick specs of the Attiny45

Features
•High Performance, Low Power AVR® 8-Bit Microcontroller
•Advanced RISC Architecture
    –  120 Powerful Instructions – Most Single Clock Cycle Execution
    –  32 x 8 General Purpose Working Registers
    –  Fully Static Operation
•Non-volatile Program and Data Memories
    –  2/4/8K Bytes of In-System Programmable Program Memory Flash
        •  Endurance: 10,000 Write/Erase Cycles
    –  128/256/512 Bytes In-System Programmable EEPROM
        •  Endurance: 100,000 Write/Erase Cycles
        –  128/256/512 Bytes Internal SRAM
        –  Programming Lock for Self-Programming Flash Program and EEPROM Data Security
•Peripheral Features
    –  8-bit Timer/Counter with Prescaler and Two PWM Channels
    –  8-bit High Speed Timer/Counter with Separate Prescaler
        •  2 High Frequency PWM Outputs with Separate Output Compare Registers
        •  Programmable Dead Time Generator
    –  USI – Universal Serial Interface with Start Condition Detector
    –  10-bit ADC
        •  4 Single Ended Channels
        •  2 Differential ADC Channel Pairs with Programmable Gain (1x, 20x)
        •  Temperature Measurement
    –  Programmable Watchdog Timer with Separate On-chip Oscillator
    –  On-chip Analog Comparator
•Special Microcontroller Features
    –  debugWIRE On-chip Debug System
    –  In-System Programmable via SPI Port
    –  External and Internal Interrupt Sources
    –  Low Power Idle, ADC Noise Reduction, and Power-down Modes
    –  Enhanced Power-on Reset Circuit
    –  Programmable Brown-out Detection Circuit
    –  Internal Calibrated Oscillator
•I/O and Packages
    –  Six Programmable I/O Lines
    –  8-pin PDIP, 8-pin SOIC, 20-pad QFN/MLF, and 8-pin TSSOP (only ATtiny45/V)
•Operating Voltage
    –  1.8 - 5.5V for ATtiny25V/45V/85V
    –  2.7 - 5.5V for ATtiny25/45/85
•Speed Grade
    –  ATtiny25V/45V/85V: 0 – 4 MHz @ 1.8 - 5.5V, 0 - 10 MHz @ 2.7 - 5.5V
    –  ATtiny25/45/85: 0 – 10 MHz @ 2.7 - 5.5V, 0 - 20 MHz @ 4.5 - 5.5V
•Industrial Temperature Range
•Low Power Consumption
    –  Active Mode: 
        •  1 MHz, 1.8V: 300 μA
    –  Power-down Mode:
        •  0.1 μA at 1.8V

ESP8266¶

For comparison I use an ESP8266 based development board.

At expressifs hompage, which is the vendor from the chip, is the datasheet available for download.

pinout diagram¶

block diagram¶

Features¶

This is a snippet from the ESP8266 wikipedia page

Features

    Processor: L106 32-bit RISC microprocessor core based on the Tensilica Xtensa Diamond Standard 106Micro running at 80 MHz[5]
    Memory:
        32 KiB instruction RAM
        32 KiB instruction cache RAM
        80 KiB user-data RAM
        16 KiB ETS system-data RAM
    External QSPI flash: up to 16 MiB is supported (512 KiB to 4 MiB typically included)
    IEEE 802.11 b/g/n Wi-Fi
        Integrated TR switch, balun, LNA, power amplifier and matching network
        WEP or WPA/WPA2 authentication, or open networks
    17 GPIO pins[6]
    SPI
    I²C (software implementation)[7]
    I²S interfaces with DMA (sharing pins with GPIO)
    UART on dedicated pins, plus a transmit-only UART can be enabled on GPIO2
    10-bit ADC (successive approximation ADC)

And the feature list from the datasheet

Wi-Fi:

    Certification: Wi-Fi Alliance
    Protocols: 802.11 b/g/n (HT20)
    Frequency Range: 2.4 GHz ~ 2.5 GHz (2400 MHz ~ 2483.5 MHz)
    TX Power: 802.11 b: +20 dBm
              802.11 g: +17 dBm
              802.11 n: +14 dBm
    Rx Sensitivity: 802.11 b: –91 dbm (11 Mbps)
                    802.11 g: –75 dbm (54 Mbps) 
                    802.11 n: –72 dbm (MCS7)
    Antenna: PCB Trace, External, IPEX Connector, Ceramic Chip

Hardware:
    CPU: Tensilica L106 32-bit processor
    Peripheral Interface: UART/SDIO/SPI/I2C/I2S/IR Remote Control
                          GPIO/ADC/PWM/LED Light & Button
    Operating Voltage: 2.5 V ~ 3.6 V
    Operating Current: Average value: 80 mA
    Operating Temperature Range: –40 °C ~ 125 °C
    Package Size: QFN32-pin (5 mm x 5 mm)
    External Interface : - 

Software :
    Wi-Fi Mode: Station/SoftAP/SoftAP+Station
    Security: WPA/WPA2
    Encryption: WEP/TKIP/AES
    Firmware Upgrade: UART Download / OTA (via network) 
    Software Development: Supports Cloud Server Development / Firmware and SDK 
                          for fast on-chip programming
    Network Protocols: IPv4, TCP/UDP/HTTP
    User Configuration: AT Instruction Set, Cloud Server, Android/iOS App

I described the way of flashing HERE