Microcontroller
Figure above 8051 Microcontroller - AT89S8253 - DIP 42
The AT89S8253 is a low-power, high-performance CMOS 8-bit microcontroller with 12K bytes of In-System Programmable (ISP) Flash program memory and 2K bytes of EEPROM data memory. The device is manufactured using Atmel’s high-density non-volatile memory technology and is compatible with the industry-standard MCS-51 instruction set and pin out.
Features
• 12K Bytes of In-System Programmable (ISP) Flash Program Memory – SPI Serial Interface for Program Downloading – Endurance: 10,000 Write/Erase Cycles
• 2K Bytes EEPROM Data Memory – Endurance: 100,000 Write/Erase Cycles
• 2.7V to 5.5V Operating Range
• 256 x 8-bit Internal RAM
• 32 Programmable I/O Lines
• Enhanced UART Serial Port with Framing Error Detection and Automatic Address Recognition
Tasks (done by the microcontroller):
a. Monitor the storage units, check each storage units’ weight sensor; the weight sensor will give a positive numerical data reading when these a parcel placed in a storage unit, otherwise a 0 to negative numerical reading will be obtained from the weight sensor. The µC will send the monitor data to the Rpi3, for processing.
b. Access Control to the storage unit(s); the microcontroller will grant, and secure access to each storage unit; based on the task the system needs to perform.