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Why is the timer a double-byte structure?

Latest Updated:03/01/2005

Question:

(Timer)   Why is the timer a double-byte structure? [2005/03/01]

Answer:

Since the term "double-byte structure" has two meanings: "8-bit prescaler + 8-bit timer", or "timer + latch", both will be explained here.

<8-bit Prescaler + 8-bit Timer>
Formerly, an 8-bit MCU had 8-bit peripheral functions, but our 8-bit MCU comes with a built-in "8-bit prescaler + 8-bit timer", enabling counts up to FFh x FFh.
We now also have products with "two 8-bit timers connected to perform as a 16-bit timer" or a built-in "16-bit timer". Please refer to the corresponding product datasheets or user’s manuals for timer types and specifications.
<Timer + Latch>
The latch enables automatic reload during timer count and the storing of read-out and write-in values in any mode. For example, with the 16-bit timer, since there is no write instruction to write data to all 16 bits at one time, the timer set value must be split into two 8-bit blocks in order to write. High/low-order data must be set as 8-bit data to the latch, and then transferred to the timer collectively as 16-bit data. Please refer to the corresponding product datasheets or user's manuals for timer types and specifications.

(#104779)

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