8086 Microprocessor
8086 Microprocessor is an advanced version of 8085 Microprocessor, designed by Intel in 1976. The number 8086 denotes the IC number of this microprocessor. It is a 16-bit microprocessor. It has 16 bits of the data bus, that is why it can read or write either 16 bit or 8 bit of data at a time.. It has 20 bits of address lines that can access 2^20 of address locations.
It works in 2 modes-
It can only perform fixed-point arithmetic instructions and not the floating point operations.
8088 Microprocessor
8088 Microprocessor is an advanced version of 8087 Microprocessor, designed by Intel in 1979. It is a 8-bit microprocessor. It has 8 bits of the data bus. As, it is a 8-bit microprocessor, it requires two complete cycles to process 16 bit data.
Also, it performs the processing of floating point data and instructions as it supports the Intel 8087 numeric co-processor.
Though the architecture and instruction set of both 8086 and 8088 processors are same, still there are differences between them. Following is the table listing the differences between the 2 microprocessors:
| S. No. | 8086 microprocessor | 8088 microprocessor |
|---|
| 1 | The data bus is of 16 bits. | The data bus is of 8 bits. |
| 2 | It has 3 available clock speeds (5 MHz, 8 MHz (8086-2) and 10 MHz (8086-1)). | It has 2 available clock speeds (5 MHz, 8 MHz) |
| 3 | The memory capacity is 512 kB. | The memory capacity is implemented as a single 1 MX 8 memory banks. |
| 4 | It has memory control pin (M/IO) signal. | It has complemented memory control pin (IO/M) signal of 8086. |
| 5 | It has Bus High Enable (BHE) signal. | It has System Status Output (SSO) signal. |
| 6 | It can read or write either 8-bit or 16-bit word at once. | It can read only 8-bit word at once. |
| 7 | Input/Output voltage level is measured at 2.5 mA. | Input/Output voltage level is measured at 2.0 mA. |
| 8 | It has 6 byte instruction queue. | It has 4 byte instruction queue as it can fetch only 1 byte at a time. |
| 9 | It draws a maximum supply current of 360 mA. | It draws a maximum supply current of 340 mA. |