EM78P5840N/41N/42N
8-Bit Microcontrollers
7.3.10 IOCE (Interrupt Mask)
Page 0 (Interrupt Mask)
Bit 7
PWM2
R/W-0
Bit 6
Bit 5
ADI
Bit 4
PWM1
R/W-0
Bit 3
Bit 2
Bit 1
Bit 0
0
-
-
-
-
-
-
-
-
-
R/W-0
Bit 1 ~ Bit 3 (undefined): These bits are not used.
Bit 4 (PWM1) : One PWM1 one period for each interrupt mask.
Bit 5 (ADI) : ADC conversion complete interrupt mask
"0" : Disable interrupt
"1" : Enable interrupt
There are four registers for the AD converter. Use one bit of the interrupt control
register (IOCE Page 0 Bit 5) to signal an interrupt when the AD conversion is completed.
The status and control register of AD (IOCB Page 1 and RE Page 0 Bit 5) indicate the
A/D conversion status or AD control. The AD data register (RB PAGE1) stores the
result of the AD conversion.
The ADI bit can be enabled or disabled in the IOCE PAGE 0 register to signal the
completion of the A/D conversion. The ADI flag is then enabled or disabled in the RE
register when AD conversion is completed. The ADI flag indicates the end of an AD
conversion. The AD converter sets the interrupt flag (ADI) in the RE Page 0 register
when a conversion is completed. The interrupt can be disabled by setting the ADI bit in
IOCE Page 0 Bit 5 to “0.”
The AD converter has eight analog input channels (AD1 ~ AD8) multiplexed into one
sample and hold to AD module. The reference voltage can be driven from the internal
power. The AD converter itself is a 10-bit successive approximation type and produces
the last significant 8-bit result in the RB Page 1 and the most significant 2 bits to R7
Page 1 Bit 4, Bit 5. A conversion is initiated by setting a control bit ADST in IOCB Page
1 Bit 0. Prior to conversion, the appropriate channel must be selected by setting IN0 ~
IN2 bits in the RE register. Enough time must be allowed to sample data. Every AD
data conversion needs 12-clock cycle time. The minimum conversion time required is
13 µs (73K sample rate). The ADST Bit in IOCB Page 1 Bit 0 must be set to begin a
conversion.
It will be automatically reset in the hardware when a conversion is completed. At the
end of the conversion, the Start bit is cleared and the the AD interrupt is activated if ADI
in IOCE Page 0 Bit 5 = 1. ADI will be set when the conversion is completed. It can be
reset in the software.
If ADI = 0 in IOCE Page 0 Bit 5 and AD starts data conversion by setting ADST(IOCB
Page 1 Bit 0) = 1, then AD will continue the conversion non-stop and the hardware
Product Specification (V1.0) 04.25.2006
(This specification is subject to change without further notice)
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ELAN [ ELAN MICROELECTRONICS CORP ]
