IBM EM78M611E manual Analog-To-Digital Converter ADC, Clock Hz Period/255 s

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EM78M611E

Universal Serial Bus Series Microcontroller

ERE [0~2] PWM Clock Prescaler

PS2		PS1		PS0	Clock (Hz)		Period/255 (s)

0		0		0	Fosc/3		0.5µ

0		0		1	Fosc/6		1µ

0		1		0	Fosc/12		2µ

0		1		1	Fosc/24		4µ

1		0		0	Fosc/48		8µ

1		0		1	Fosc/96		16µ

1		1		0	Fosc/192		32µ

1		1		1	Fosc/384		64µ

ERE [6, 7] PWM1/PWM2 Enable Bit

0 : Disable

1 : Enable

8.11 Analog-To-Digital Converter (ADC)

8.11.1 Function Description

The Analog to Digital converter consists of a 5-bit analog multiplexer, one Control Register (ERA), and two data registers (RBS & RCS) for 10-bit resolution.

The ADC module utilizes successive approximation to convert the unknown analog signal to a digital value. The result is fed to the ADDATA. Input channels are selected by the analog input multiplexer via the ADCS/RAS bits AD0~AD4.

10-bit resolution: 0x00-00~0xC0-FF (0b11000000-11111111)

Start (0x00-00): 0 Vref~(1/1024) ⋅ Vref

Full (0xC0-FF): (1023/1024) ⋅ Vref~Vref

Conversion Time: 12 clock time of internal clock source

8.11.2 Control Register

ERA (AD Channel Select Register) Default Value: (0B_0001_1111)

Bit 7	Bit 6	Bit 5	Bit 4	Bit 3	Bit 2	Bit 1	Bit 0

ADC

0

0

AD4

AD3

AD2

AD1

AD0

Product Specification (V1.11) 04.20.2007

• 29

(This specification is subject to change without further notice)

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Contents EM78M611E Trademark Acknowledgments 2.1 Appendix Product Specification V1.1Features General DescriptionUniversal Serial Bus Series Microcontroller Product Specification V1.1 Type Definition ApplicationOriginal With Both VNN Pin AssignmentEM78M611EXBP/BM/DM 20-Pin DIP/SOP/SSOP Pin Description Symbol FunctionALU ACC Data & Control BUS Block DiagramProgram Memory Function DescriptionSpecial Purpose Register Data Memory2.2 R1 Timer / Clock Counter Default Value 0B00000000 2.3 R2 Program Counter & Stack Default Value 0B00000000Operation Registers 2.4 R3 Status Register Default Value0B00011XXX R3 0 Carry/Borrow FlagBit Program Memory Page Address Condition2.5 R4 RAM Select Register Default Value 0B00XXXXXX EP0Busy Stall RF Interrupt Status Register Default Value 0B00000000Accumulator Control RegistersTCC Rate WDT Rate Control Register Default Value 0B00111111PS/2 Operation ModeDualFrq.1 DualFrq.0 Frequency Bit P96 P95 P94 P93 P92 P91 P90PH95 PH93 PU8 PU6 PU5 USB Application FIFOs Extra Control RegisterUSB Device Controller USB ApplicationSaving Power Mode ResetInterrupt Dual Clock ModeFunction Description Pattern Detect Application PDASampling Rate and Debounce Length Control RegisterSR.2 SR.1 SR.0 Sampling Rate DB.2 DB.1 DB.0 Debounce TimePulse Width Modulation PWM Erepwm Control Register Default Value 0B00000001Duty Cycle R10 PWM1 Duty Cycle RegisterERA AD Channel Select Register Default Value 0B00011111 Analog-To-Digital Converter ADCClock Hz Period/255 s Channel Port ERB AD LSB Data Register Default Value 0B00000000ERC AD MSB Data Register Default Value 0B00000000 ERD AD Control Register Default Value 0B00000000Command Value Action Execution Time Symbol Min Max Unit DC Electrical CharacteristicSymbol Parameter Condition Min Type Max Unit Absolute Maximum RatingsUSB Interface Application Circuit Address Name Bit Bit1 Default Value Special Register MapOperation Registers Extra Register IOCA3 = Address Name Bit Default ValueBinary Instruction Hex Mnemonic Operation Status Affected Instruction SetThis instruction is not recommended for RE, RF operation Code Option Register Address11 16ms Bits 4~12 User ID Address EM78M611E