Intel 8086

Intel 8086 is the first in the long line of Intel's x86 chips. Released in 1978.

Registers[1][2]

• AX - Primary accumulator - 16-bit, made up of 2 8-bit registers AH and AL (which will update with AX and vice versa), arithmetic and logical instructions

• BX - Base register - 16-bit, made up of BH and BL (same details as AX),  stores offsets for memory addressing

• CX - Loop counter - 16-bit, made up of CH and CL (same details as AX),  

• DX - Data register - 16-bit, made up of DH and DL (same details as AX), I/O and extended arithmetic

• SI - Source Index - 16-bit

• DI - Destination Index - 16-bit

• BP - Base Pointer - 16-bit

• SP - Stack Pointer - 16-bit

• IP - Instruction Pointer - 16-bit

• CS - Code Segment - 16-bit

• DS - Data Segment - 16-bit

• ES - Extra Segment - 16-bit

• SS - Stack Segment - 16-bit

• Flags register (left to right):

  • N/A

  • N/A

  • N/A

  • N/A

  • Overflow Flag

  • Direction Flag

  • Interrupt flag

  • Trap Flag

  • Sign flag

  • Zero flag

  • N/A

  • Auxiliary carry flag

  • N/A

  • Parity flag

  • N/A

  • Carry flag