MC68HC711E20CFN2 Freescale Semiconductor, MC68HC711E20CFN2 Datasheet - Page 214

• Manufacturer Part Number: MC68HC711E20CFN2
• Description: IC MCU 20K 2MHZ OTP 52-PLCC
• Manufacturer: Freescale Semiconductor
• Series: HC11r

Specifications of MC68HC711E20CFN2

• Core Processor: HC11
• Core Size: 8-Bit
• Speed: 2MHz
• Connectivity: SCI, SPI
• Peripherals: POR, WDT
• Number Of I /o: 38
• Program Memory Size: 20KB (20K x 8)
• Program Memory Type: OTP
• Eeprom Size: 512 x 8
• Ram Size: 768 x 8
• Voltage - Supply (vcc/vdd): 4.5 V ~ 5.5 V
• Data Converters: A/D 8x8b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 52-PLCC
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

Analog-to-Digital (A/D) Converter
10.4 A/D Converter Power-Up and Clock Select
Technical Data
214
1. Can be written only once in first 64 cycles out of reset in normal modes or at any time in special modes
Address:
Bit 7 of the OPTION register controls A/D converter power-up. Clearing
ADPU removes power from and disables the A/D converter system.
Setting ADPU enables the A/D converter system. Stabilization of the
analog bias voltages requires a delay of as much as 100 s after turning
on the A/D converter. When the A/D converter system is operating with
the MCU E clock, all switching and comparator operations are inherently
synchronized to the main MCU clocks. This allows the comparator
output to be sampled at relatively quiet times during MCU clock cycles.
Since the internal RC oscillator is asynchronous to the MCU clock, there
is more error attributable to internal system clock noise. A/D converter
accuracy is reduced slightly while the internal RC oscillator is being used
(CSEL = 1).
ADPU — A/D Power-Up Bit
CSEL — Clock Select Bit
IRQE — Configure IRQ for Edge-Sensitive Only Operation
Reset:
Read:
Figure 10-4. System Configuration Options Register (OPTION)
Write:
Refer to
0 = A/D powered down
1 = A/D powered up
0 = A/D and EEPROM use system E clock.
1 = A/D and EEPROM use internal RC clock.
$1039
ADPU
Bit 7
0
Analog-to-Digital (A/D) Converter
Section 5. Resets and
= Unimplemented
CSEL
6
0
IRQE
5
0
(1)
DLY
4
1
(1)
Interrupts.
CME
3
0
M68HC11E Family — Rev. 3.2
2
0
CR1
1
0
(1)
MOTOROLA
CR0
Bit 0
0
(1)