SH7052 datasheet(335/919 Pages) RENESAS

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Down-Counters 8A to 8P (DCNT8A to DCNT8P): Down-counters 8A to 8P (DCNT8A to

DCNT8P) are 16-bit readable/writable registers that count on an input clock. The input clock is

selected with prescaler register 1 (PSCR1) and the timer control register (TCR).

Bit:

Bit name:

Initial value:

R/W: R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W

When the one-shot pulse function is used, DCNT8x starts counting down when the corresponding

DSTR bit is set to 1 by the user program after the DCNT8x value has been set. When the DCNT8x

value underflows, DSTR and DCNT8x are automatically cleared to 0, and the count is stopped. At

the same time, the corresponding channel 8 timer status register 8 (TSR8) status flag is set to 1.

When the offset one-shot pulse function is used, on compare-match with a channel 1 or 2 general

trigger mode register (TRGMDR) (for channel 1 only) ) when the corresponding timer connection

set to 1 and the down-count is started. When the DCNT8x value underflows, the corresponding

DSTR bit and DCNT8x are automatically cleared to 0, the count is stopped, and the output is

inverted, or, if a one-shot terminate register (OTR) setting has been made to forcibly terminate

output by means of a trigger, DSTR is cleared to 0 by a channel 1 or 2 compare-match between

GR and OCR, the count is forcibly terminated, and the output is inverted. The output is inverted

for whichever is first. At the same time, the corresponding channel 8 TSR8 status flag is set to 1.

The DCNT8x counters can only be accessed by a word read or write.

The DCNT8x counters are initialized to H'0000 by a power-on reset, and in hardware standby

mode and software standby mode.

For details, see sections 10.3.5, One-Shot Pulse Function, and 10.3.6, Offset One-Shot Pulse

Function and Output Cutoff Function.

10.2.17

Event Counters (ECNT)

The event counters (ECNT) are 8-bit up-counters. The ATU-II has six ECNT counters in channel

Channel

Abbreviation

Function

ECNT9A, ECNT9B,

ECNT9C, ECNT9D,

ECNT9E, ECNT9F

8-bit event counters

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