EM78P350N
8-Bit Microprocessor with OTP ROM
The table below shows the relationship between Tct and the maximum operating
frequencies.
Operation Max. Operation Max. Conversion
CKR1: CKR0
Max. Conversion Rate
Mode
Fosc/16
Fosc/4
Frequency
4MHz
1MHz
16MHz
-
Rate/Bit
00
01
10
11
250kHz (4µs) 15 × 4µs=60µs (16.7kHz)
250kHz (4µs) 15 × 4µs=60µs (16.7kHz)
250kHz ( 4µs) 15 × 4µs=60µs (16.7kHz)
14kHz (71µs) 15 × 71µs=1065µs (0.938kHz)
Fosc/64
Internal RC
NOTE
■ Pin not used as an analog input pin can be used as regular input or output pin.
■ During conversion, do not perform output instruction to maintain precision for all the
pins.
6.9.5 ADC Operation during Sleep Mode
In order to obtain a more accurate ADC value and reduce power consumption, the AD
conversion remains operational during sleep mode. As the SLEP instruction is
executed, all the MCU operations will stop except for the Oscillator, TCC, Timer 1,
Timer 2, Timer 3, Timer 4 and AD conversion.
The AD Conversion is considered completed as determined by:
1. ADRUN bit of R9 register is cleared (“0” value)
2. Wake-up from AD conversion (where it remains in operation during sleep mode)
The results are fed into the ADDATA, ADDATA1H, and ADDATA1L registers when the
conversion is completed. If the ADWE is enabled, the device will wake up. Otherwise,
the AD conversion will be shut off, no matter what the status of ADPD bit is.
6.9.6 Programming Process/Considerations
6.9.6.1 Programming Process
Follow these steps to obtain data from the ADC:
1. Write to the 8 bits (ADE7:ADE0) on the Bank 2 R8 (AISR) register to define the
characteristics of R6 (digital I/O, analog channels, or voltage reference pin).
2. Write to the Bank 2 R9/ADCON register to configure the AD module:
a) Select ADC input channel (ADIS2: ADIS0).
b) Define AD conversion clock rate (CKR1: CKR0).
c) Select the VREFS input source of the ADC.
d) Set the ADPD bit to 1 to begin sampling.
3. Set the ADWE bit, if the wake-up function is employed.
4. Set the ADIE bit, if the interrupt function is employed.
5. Write “ENI” instruction, if the interrupt function is employed.
Product Specification (V 1.0) 09.14.2006
(This specification is subject to change without further notice)
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ELAN [ ELAN MICROELECTRONICS CORP ]
