s3c72m9 Samsung Semiconductor, Inc., s3c72m9 Datasheet - Page 347

• 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.

S3C72M5/C72M7/C72M9/P72M9 (Preliminary Spec)
COMPARATOR MODE REGISTER (CMOD)
The comparator mode register CMOD is an 8-bit register that is used to select the operation mode of the
comparator. It is mapped to addresses FD2H–FD3H and can be manipulated using 8-bit memory instructions.
Based on the CMOD.5 bit setting, an internal or an external reference voltage is input for the comparator, as follows:
When CMOD.5 is set to logic zero:
— A reference voltage is selected by the CMOD.0 to CMOD.3 bit settings.
— P4.0–P4.2 are used as analog input pins.
— The internal digital to analog converter generates 16 reference voltages.
— The comparator can detect 150-mV differences between the reference voltage and the analog input voltages.
— Comparator results are written into bit0–bit2 of the comparison result register (CMPREG).
When CMOD.5 is set to logic one:
— An external reference voltage is supplied from P4.2/CIN2.
— P4.0 and P4.1 are used as the analog input pins.
— The comparator can detect 150-mV differences between the reference voltage and the analog input voltages.
— Bits 0 and 1 in the CMPREG register contain the results.
Bit 6 in the CMOD register controls conversion time while bit 7 enables or disables comparator operation to reduce
power consumption. A RESET signal clears all bits to logic zero, causing the comparator to enter stop mode.
CMOD.7
1: Comparator operation enable
0: Comparator operation disable
CMOD.6
1: Conversion time (4 x 2
0: Conversion time (4 x 2
Figure 14-2. Comparator Mode Register (CMOD) Organization
CMOD.5
1: CIN2; external reference, CIN0 and CIN1; analog input
0: Internal reference, CIN0-2; analog input
5
6
/fx, 30.5 s @4.19 MHz)
/fx, 244.4 s @4.19 MHz)
"0"
CMOD.3
CMOD.2
Reference voltage (V
V
DD
x (n + 0.5)/16, n = 0 to 15
CMOD.1
CMOD.0
REF
) selection;
COMPARATOR
FD6H-FD7H
14-3