12 8-Bit Timer (T8F); 8-Bit Timer Overview - Epson S1C17001 Technical Manual

12 8-bit Timer (T8F)

12.1 8-bit Timer Overview

The S1C17001 incorporates an 8-bit timer with Fine mode.
The 8-bit timer consists of an 8-bit presettable down counter and an 8-bit reload data register holding the preset
values. The timer counts down from the initial value set in the reload data register and outputs an underflow signal
when the counter underflows. The underflow signal is used to generate an interrupt and UART clock. The under-
flow cycle can be programmed by selecting the prescaler clock and reload data, enabling the application program to
obtain time intervals and serial transfer speeds as required. Fine mode provides a function that minimizes transfer
rate errors.
Figure 12.1.1 illustrates the 8-bit timer configuration.
Prescaler
To ITC
To UART
S1C17001 TECHNICAL MANUAL
8-bit timer
DF[3:0]
Count clock selection
-
PCLK 1/1 to 1/16 K
PRUN
RUN/STOP control
Interrupt request
Serial transfer clock
Figure 12.1.1: 8-bit timer configuration
Timer reset
Reload data register
Down counter
Control circuit
Fine mode setting
EPSON
12 8-BIT TIMER (T8F)
PRESER
T8F_TR
T8F_TC
Underflow
TFMD[3:0]
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