em78p5842 ELAN Microelectronics Corp, em78p5842 Datasheet - Page 21

• Manufacturer Part Number: em78p5842
• Description: 8-bit Micro-controller
• Manufacturer: ELAN Microelectronics Corp

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* This specification is subject to change without notice.
IOC8
IOC9 (PORT9 I/O control, PORT9 switches)
PAGE0 (PORT9 I/O control register)
Bit 0 ~ Bit 7 (IOC90 ~ IOC97) : PORT9(0~7) I/O direction control register
PAGE1 (Unused), This page is not allowed to use.
IOCA (Unused)
PAGE0(undefined) not allowed to use
PAGE1 Unused
Bit 0(AD7S) : Select normal I/O PORT92 pin or channel 7 input AD7 pin of ADC
Bit2 ~ Bit7 are undefined register, they are not allowed to use.
IOCB (ADC control)
PAGE0 (Unused), This page is not allowed to use
PAGE1 (ADC control bits)
R/W-1
R/W-0
IOC97
Bit 1(AD8S) : Select normal I/O PORT93 pin or channel 8 input AD8 pin of ADC
IN2
Bit 0(ADST) : AD converter start to sample
Bit 1 : (undefined) not allowed to use. This bit must clear to 0.
Bit 2(ADPWR) : AD converter power control, 1/0 Î enable/disable.
Bit 3 ~ Bit 4 (ADCLK0 ~ ADCLK1) : AD circuit ‘s sampling clock source.
0 Î put the relative I/O pin as output
1 Î put the relative I/O pin into high impedance
X
0 Î P92 (I/O PORT92) pin is selected
1 Î AD7 (Channel 7 input of ADC) pin is selected
0 Î P93 (I/O PORT93) pin is selected
1 Î AD8 (Channel 8 input of ADC) pin is selected
7
By setting to “1”, the AD will start to sample data. This bit will be cleared by hardware automatically after a
sampling.
7
7
-
For Crystal mode:
For IRC or ERIC mode, AD converter rate will change by oscillator. The formula for input frequency and AD
converter rate is: AD converter rate = oscillator / 4 / (2^ADCLK)/12
For example, if input CLK = 4M Hz:
ADCLK1 ADCLK0
(Unused), not allowed to use
0
0
1
1
R/W-1
R/W-0
IOC96
IN1
X
6
6
6
-
0
1
0
1
R/W-1
R/W-0
IOC95
IN0
X
5
5
5
-
Sampling rate
ADCLK1 ADCLK0 ADPWR
R/W-1
R/W-0
IOC94
74.6K
37.4K
18.7K
9.3K
X
4
4
4
-
R/W-1
R/W-0
IOC93
3
3
X
3
-
Operation voltage
19
R/W-1
R/W-0
>=3.5V
>=3.0V
>=2.5V
>=2.5V
IOC92
2
2
X
2
-
R/W-1
IOC91
R/W-0
AD8S
X
-
1
1
1
R/W-1
R/W-0
ADST
IOC90
R/W-0
AD7S
0
0
0
EM785840/5841/5842
8-bit Micro-controller
2004/11/10 V1.2