s3c72m9 Samsung Semiconductor, Inc., s3c72m9 Datasheet - Page 278

• Manufacturer Part Number: s3c72m9
• Description: The S3c72m5/s3c72m7/s3c72m9 Single-chip Cmos Microcontroller Has Been Designed For High Performance Using Samsung S
• Manufacturer: Samsung Semiconductor, Inc.

TIMERS and TIMER/COUNTERS
TC1 MODE REGISTER (TMOD1A)
TMOD1A is the 8-bit mode register for timer/counter 1. It is addressable by 8-bit write instructions. The TMOD1A.3
bit is also 1-bit write addressable. RESET clears all TMOD1A bits to logic zero. Following a RESET, timer/counter 1
is disabled.
TMOD1A.7 is the mode selection bit for one 16-bit timer/counter or two 8-bit timer/counters. TMOD1A.2 is the
enable/disable bit for timer/counter 1. When TMOD1A.3 is set to "1", the contents of TCNT1, IRQT1, and TOL1 are
cleared, counting starts from 0000H, and TMOD1A.3 is automatically reset to "0" for normal TC1 operation. When
TC1 operation stops (TMOD1A.2 = "0"), the contents of the TC1 counter register, TCNT1, are retained until TC1 is
re-enabled.
The TMOD1A.6, TMOD1A.5, and TMOD1A.4 bit settings are used together to select the TC1 clock source. This
selection involves two variables:
— Synchronization of timer/counter operations with either the rising edge or the falling edge of the clock signal
— Selection of one of four frequencies, based on division of the incoming system clock frequency, for use in
11-30
TMOD1A.7
TMOD1A.6
TMOD1A.5
TMOD1A.4
TMOD1A.3
TMOD1A.2
TMOD1A.1
TMOD1A.0
FA0H
FA1H
Bit Name
input at the TCL1 pin, and
internal TC1 operations.
TMOD1A.3
TMOD1A.7
Setting
0,1
0,1
1
0
1
0
0
Table 11-10. TC1 Mode Register (TMOD1A) Organization
TMOD1A.2
TMOD1A.6
Configure as one 16-bit timer/counter 1 or two 8-bit
timer/counters 1A, 1B.
Specify input clock edge and internal frequency
Clear TCNT1, IRQT1, and TOL1 and resume counting immedi-
ately (This bit is automatically cleared to logic zero immediately
after counting resumes).
Disable timer/counter 1; retain TCNT1 contents
Enable timer/counter 1
Always logic zero
Always logic zero
TMOD1A.5
"0"
Resulting TC1 Function
TMOD1A.4
"0"
S3C72M5/C72M7/C72M9/P72M9 (Preliminary Spec)
Address
FA1H
FA0H