8051 Unconditional Branch Instruction. 8051 Micro-controller; by admin - April 23, 2019 May 10, 2021 0. Share on Facebook Share. Send email Mail. Print Print. 8051 Unconditional Branch Instruction JMP. If another interrupt was pending when the RETI instruction is executed, 8051 Microcontroller Instruction Set. The Microcontroller 8051 is a 8-bit microcontroller with 40 pin DIP (dual in-line package) integrated circuit. The 8051 ICs were built in HMOS, HMOS II and CHMOS technologies. 32 1 RETI 33 1 RLC A 34 2 ADDC A, #immed 35 2 ADDC A, direct 36 1 ADDC A, @R0 37 1 ADDC A, @R1 38 1 ADDC A, R0 39 1 ADDC A, R1 Two ports on the 8051 microcontroller; pins 12 (INT0) and 13 (INT1) in port 3 can be used as external interrupts. Once the microcontroller gets a signal from an external device on these ports, it interrupts its operation and starts executing the ISR meant for the external interrupt. The microcontroller can be interrupted by two different signals. THE 8051 INSTRUCTION SET All commands in alphabetic order: ACALL addr11 DIV AB LJMP addr16 RETI ADD A,