MC68HC705JP7CDW Freescale Semiconductor, MC68HC705JP7CDW Datasheet - Page 92

• Manufacturer Part Number: MC68HC705JP7CDW
• Description: IC MCU 8BIT 28-SOIC
• Manufacturer: Freescale Semiconductor
• Series: HC05r

Specifications of MC68HC705JP7CDW

• Core Processor: HC05
• Core Size: 8-Bit
• Speed: 2.1MHz
• Connectivity: SIO
• Peripherals: POR, Temp Sensor, WDT
• Number Of I /o: 22
• Program Memory Size: 6KB (6K x 8)
• Program Memory Type: OTP
• Ram Size: 224 x 8
• Voltage - Supply (vcc/vdd): 2.7 V ~ 5.5 V
• Data Converters: A/D 4x12b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 28-SOIC (7.5mm Width)
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Eeprom Size: -

Analog Subsystem
8.7 Voltage Comparator Features
The two internal comparators can be used as simple voltage comparators if set up as described in
Table
the analog interrupt. Both comparators can also be active in the stop mode, but cannot directly restart the
part. However, the comparators can directly drive PB4 which can then be connected externally to activate
either a port interrupt on the PA0:3 pins or the IRQ/V
8.7.1 Voltage Comparator 1
Voltage comparator 1 is always connected to two of the port B I/O pins. These pins should be configured
as inputs and have their software programmable pulldowns disabled. Also, the negative input of voltage
comparator 1 is connected to the PB3/AN3/TCAP and shared with the input capture function of the 16-bit
programmable timer. Therefore, the timer input capture interrupt should be disabled so that changes in
the voltage on the PB3/AN3/TCAP pin do not cause unwanted input capture interrupts.
The output of comparator 1 can be connected to the port logic driving the PB4/AN4/TCMP/CMP1 pin such
that the output of the comparator is ORed with the PB4 data bit and the OLVL bit from the 16-bit timer.
This capability requires that the OPT bit is set in the COPR at location $1FF0 as in
COE1 bit is set in the ASR at location $001E.
OPT — Optional Features Bit
92
The OPT bit enables two additional features: direct drive by comparator 1 output to PB4 and voltage
offset capability to sample capacitor in analog subsystem.
1 = Optional features enabled
0 = Optional features disabled
8-8. Both comparators can be active in the wait mode and can directly restart the part by means of
Address:
Comparator
Reset:
Read:
Write:
MC68HC705JJ7 • MC68HC705JP7 Advance Information Data Sheet, Rev. 4.1
1
2
$1FF0
EPMSEC
Bit 7
U
Table 8-8. Voltage Comparator Setup Conditions
Figure 8-12. COP and Security Register (COPR)
ISEN = 0
Current
affected
Source
Enable
Not
= Unimplemented
OPT
U
6
Discharge
ISEN = 0
Disable
affected
Device
Not
U
5
U = Unaffected
DDRB2 = 0
DDRB3 = 0
DDRB0 = 0
DDRB1 = 0
Port B Pin
as Inputs
U
4
PP
pin.
U
3
Pulldowns
Port B Pin
PDIB2 = 1
PDIB3 = 1
PDIB0 = 1
PDIB1 = 1
Disabled
U
2
Prog. Timer Input
ICEN = 0
IEDG = 1
Capture
U
affected
1
Source
Not
Figure
Freescale Semiconductor
COPC
Bit 0
U
8-12, and the