8051 PIC Microcontroller Time Delay Calculator

8051 PIC Microcontroller

The 8051 PIC microcontroller’s time delay feature makes it possible to integrate precise timing intervals into electronic circuits.
It provides exact control over timing operations within the circuit by generating precise delays using the internal clock and software programming of the microcontroller.

To introduce controlled pauses or gaps in program execution, the time delay feature of the 8051 PIC microcontroller is primarily used for this purpose.
It makes it possible to synchronize several processes, start certain operations after a predetermined amount of time, and precisely time tasks in applications that include time-sensitive tasks.

The 8051 microcontroller, unveiled by Intel in 1981, represents an 8-bit computing marvel. Renowned for its versatility and ubiquity, it finds extensive application across diverse sectors. Below are salient features of the 8051 microcontroller:

Architecture:”The 8051 microcontroller, an 8-bit device, adopts a Harvard architecture, featuring distinct buses allocated for program and data transmission.”

Instruction Set: The 8051 microcontroller has a set of 33 single-byte and 7 multi-byte instructions.

Memory: The 8051 microcontroller possesses a collective memory capacity of 4KB, comprising 128 bytes of internal RAM and 4KB of EPROM.

Ports: The 8051 microcontroller has three 8-bit ports (P0, P1, and P2) and one 16-bit port (P3).

Timers/Counters: The 8051 microcontroller has two 16-bit timers/counters (Timer 0 and Timer 1).

Serial Communication: “The 8051 microcontroller features a serial communication interface (SCI) suitable for facilitating serial communication.”

Power Consumption: The 8051 microcontroller is designed to be low power and can operate at a power consumption of around 10mA.

To generate a time delay in an 8051 microcontroller, you can use several methods. Here are a few:

Method 1: Using the DELAY subroutine

The DELAY subroutine offers a basic means of creating time delays. Nonetheless, its reliability is limited, as it relies on the count of machine cycles and clock periods per machine cycle, variables that may differ across various 8051 microcontrollers.

Method 2: Using Timers

Timers offer greater precision compared to the DELAY subroutine. Employing timers involves configuring them to produce a set number of clock cycles and subsequently assessing the timer value to ascertain the completion of the delay.

Method 3: Using a Loop

“Another approach is employing a loop for creating a time delay. In this method, a counter is decremented within the loop, and the loop continues until the counter reaches zero. While considered more dependable than the DELAY subroutine, it remains reliant on the machine’s cycle count per instruction.”


  • Embedded Systems
  • Automation and Control Systems
  • Instrumentation and Measurement
  • Communication Systems
  • Consumer electronics


When contrasting the PIC microcontroller with the 8051 microcontroller, it’s evident that the latter is strictly an 8-bit microcontroller, whereas the PIC microcontroller comes in both 8-bit and 16-bit variants, contingent on the particular model. While renowned for its simplicity and versatility across various applications, the PIC microcontroller boasts a more intricate instruction set and offers advanced functionalities not found in the 8051 microcontroller.

Make use of this online tool to determine your 8051 PIC microcontroller’s time delay. To precisely calculate the time delay, simply input the intended run time and the clock frequency.

You may use the input parameters of clock frequency and desired run duration to precisely calculate the time delay of your 8051 PIC microcontroller (UC) device with the help of this digital electronics calculator.

Note : Don’t end with comma ( , )

Microcontroller Clock Frequency
Desired Timer Run-Time
Single Timer TIC Duration
8-bit Timer Counter Max Run-Time
16-bit Timer Counter Max Run-Time
8-Bit DRT Reload Value
16-Bit DRT Reload Value


\[TIC12 = 1 / (mhz / 12)TIC6 = 1 / (mhz / 6) \\8-bit \;Timer \;Counter\; Maximum\; Run-Time\; for\; 12\; clock = TIC12 * 256 / 1000 \\8-bit\; Timer\; Counter\; Maximum\; Run-Time\; for\; 6\; clock = TIC6 * 256 / 1000 \\16-bit\; Timer\; Counter\; Maximum\; Run-Time\; for\; 12\; clock = TIC12 * 65536 / 1000 \\16-bit\; Timer\; Counter\; Maximum\; Run-Time\; for\; 6\; clock = TIC6 * 65536 / 1000 \\8-Bit\; DRT\; Reload\; Value\; for\; 12\; clock = 256 -(DRT / TIC12 * 1000) \\8-Bit\; DRT\; Reload\; Value\; for\; 6\; clock = 256 -(DRT / TIC6 * 1000) \\16-Bit\; DRT\; Reload\; Value\; for\; 12\; clock = 65536 -(DRT / TIC12 * 1000) \\16-Bit\; DRT\; Reload; Value\; for\; 6\; clock = 65536 -(DRT / TIC6 * 1000)\]

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