Question

What is the operation for mode 0?

(a) 13-bit timer mode, 8-bit timer/counter THx and TLx as 5-bit prescalar

(b) 16-bit timer mode, 16-bit timer/counter THx and TLx are cascaded, no prescalar

(c) 8-bit auto reload mode, 8-bit auto reload time/counter; THx holds a value which is to be reloaded into TLx each time it overflows

(d) Spilt timer mode

The question was asked during a job interview.

My question is from Microcontroller (8051- Pin, Registers, Timers) in portion Prototyping Embedded Devices of IOT

Answer 1

The correct choice is (a) 13-bit timer mode, 8-bit timer/counter THx and TLx as 5-bit prescalar

To elaborate: Mode 0 is exactly same like mode 1 except that it is a 13-bit timer instead of 16-bit. The 13-bit counter can hold values between 0000 to 1FFH in Th-Tl.