Internal RC Oscillator Mode | IBM EM78P259N/260N manual

EM78P259N/260N

8-Bit Microprocessor with OTP ROM

Based on the above reasons, it must be kept in mind that all supply voltage, the operation temperature, the components of the RC oscillator, the package types, and the way the PCB is layout, have certain effect on the system frequency.

The RC Oscillator frequencies:

Cext	Rext		Average Fosc 5V, 25°C	Average Fosc 3V, 25°C

	3.3k		3.5 MHz	3.2 MHz
20 pF	5.1k		2.5 MHz	2.3 MHz
20 pF	10k		1.30 MHz	1.25 MHz
	10k		1.30 MHz	1.25 MHz
	100k		140kHz	140kHz
	3.3k		1.27 MHz	1.21 MHz
100 pF	5.1k		850kHz	820kHz
100 pF	10k		450kHz	450kHz
	10k		450kHz	450kHz
	100k		48kHz	50kHz
	3.3k		560kHz	540kHz
300 pF	5.1k		370kHz	360kHz
300 pF	10k		196kHz	192kHz
	10k		196kHz	192kHz
	100k		20kHz	20kHz

Note: 1: Measured based on DIP packages.

2: The values are for design reference only.

3: The frequency drift is ± 30%.

6.11.4 Internal RC Oscillator Mode

EM78P259N/260N offers a versatile internal RC mode with default frequency value of 4MHz. Internal RC oscillator mode has other frequencies (1MHz, 8MHz, and 455kHz) that can be set by Code Option (Word 1), RCM1, and RCM0. The Table below describes the EM78P259N/260N internal RC drift with voltage, temperature, and process variation.

Internal RC Drift Rate (Ta=25°C, VDD=5V±5%, VSS=0V)

	Internal	Drift Rate
	Internal
	RC Frequency Temperature	Voltage	Process
	(-40°C ~ +85°C)	(2.3V~5.5V)	Process
	(-40°C ~ +85°C)	(2.3V~5.5V)

Total

4MHz	±10%	±5%
8MHz	±10%	±6%
1MHz	±10%	±5%
455MHz	±10%	±5%

±4%

±4%

±4%

±4%

±19%

±20%

±19%

±19%

Note: These are theoretical values provided for reference only. Actual values may vary depending on the actual process.

64 •	Product Specification (V1.2) 05.18.2007
	(This specification is subject to change without further notice)

Image 70

IBM EM78P259N/260N manual Internal RC Oscillator Mode, Cext Rext Average Fosc 5V, 25C Average Fosc 3V, 25C

Contents

EM78P259N/260N Elan Microelectronics Corporation Contents Analog-To-Digital Converter ADC Reset and Wake-upTCC/WDT and Prescaler 6.1 11.3 11.111.2 11.4 Doc. Version Revision Description Date General Description FeaturesBit Microprocessor with OTP ROM Pin DIP/SOP Block DiagramPin Assignment Pin DIP/SOP/SSOP Pin Description Symbol Pin No Type FunctionEM78P259NP/M EM78P260NP/M/KM 1 R0 Indirect Address Register Function DescriptionOperational Registers 2 R1 Time Clock /Counter EM78P259N/260N Bit Microprocessor with OTP ROM Data Memory Configuration Cont Bit 5 R4 RAM Select RegisterBit 4 T Bits 5~0 7 R7 Port Bit 7 ~ Bit 4 C3 ~ C0 Calibrator of internal RC mode6 R5 ~ R6 Port 5 ~ Port Bit 7 ~ Bit 8 R8 Aisr ADC Input Select Register 9 R9 Adcon ADC Control Register Bit 3 Adpd Bit 5 ~ Bit 3 VOF2 ~ VOF0 Offset voltage bits RA Adoc ADC Offset Calibration RegisterRB Addata Converted Value of ADC Bit 2 ~ Bit 0 Unimplemented, read as ‘0’ RD ADDATA1L Converted Value of ADC RC ADDATA1H Converted Value of ADCRE Interrupt Status 2 & Wake-up Control Register 16 R10 ~ R3F RF Interrupt Status 2 RegisterAll of these are 8-bit general-purpose registers Accumulator Special Purpose RegistersControl Register Bit 7 & Bit 6 Not used 3 IOC50 ~ IOC70 I/O Port Control Register4 IOC80 Comparator and Tcca Control Register Bit 4 & Bit 3 COS1 & COS0 Comparator/OP Select bits Tccc signal source Bit 6 Tccben Tccb enable bit 0 = disable TccbBit 4 Tccbte Tccb signal edge Bit 0 Tcccte Tccc signal edge IOCA0 IR and Tccc Scale Control Register Bit 1 LGP Bit 3 IREBit 2 HF Bit 0 Iroute Bit PD57 PD56 PD55 PD54 PD53 PD52 PD51 PD50 IOCB0 Pull-down Control RegisterIOCC0 Open-Drain Control Register Bit OD67 OD66 OD65 OD64 OD63 OD62 OD61 OD60 IOCE0 WDT Control & Interrupt Mask Registers IOCD0 Pull-high Control RegisterBit PH57 PH56 PH55 PH54 PH53 PH52 PH51 PH50 = Enable Lpwtif interrupt Lpwtif interrupt enable bit= Disable Lpwtif interrupt IOCF0 Interrupt Mask Register 12 IOC51 Tcca Counter 13 IOC61 Tccb Counter 14 IOC71 TCCBH/MSB Counter 15 IOC81 Tccc Counter IOCA1 High Time Register 16 IOC91 Low Time RegisterIOCB1 High/Low Time Scale Control Register Bit 2 ~ Bit 0 LTS2 ~ LTS0 Low time scale bits IOCC1 TCC Prescaler CounterTCC prescaler counter can be read and written to TCC/WDT and Prescaler I/O Ports MUX I/O Port and I/O Control Register Circuit for P60 /INT I/O Port and I/O Control Register Circuit for Port 50 ~ P57 Usage of Port 5 Input Change Wake-up/Interrupt Function Reset and Wake-upReset and Wake-up Operation Wake-up Wake-up and Interrupt EM78P259N/260N Select Segment Signal Sleep Mode Normal Mode Comparator Address Name Reset Type Bit Following summarizes the initialized values for registers Name Reset Type Bit HTR7 HTR6 HTR5 HTR4 HTR3 HTR2 HTR1 HTR0 Aisr Controller Reset Block Diagram Tcif T and P Status under Status R3 Register InterruptEvent EM78P259N/260N Reti Interrupt Vector Interrupt Status Priority 1.1 R8 Aisr ADC Input Select Register Analog-to-Digital Converter ADCADC Control Register AISR/R8, ADCON/R9, ADOC/RA Bit 7 ~ Bit 3 ADE3 Bit 2 ADE2 P54/TCC/VREF Pin Priority High Medium Low 1.2 R9 Adcon AD Control RegisterP54 = ADC is operating While the CPU is operatingRA Adoc AD Offset Calibration Register ADC Sampling Time ADC Operation during Sleep ModeADC Data Register ADDATA/RB, ADDATA1H/RC, ADDATA1L/RD AD Conversion Time Programming Process Programming Process/ConsiderationsFollow these steps to obtain data from the ADC ADC Control Register Sample Demo Programs Define a General RegisterDefine a Control Register Define Bits in Adcon AD power on Infrared Remote Control Application/PWM Waveform Generation Overview Function Description Fcarrier IRE Irout IR/PWM Related Status/Data Registers Programming the Related RegistersAddress Name Bit EM78P259N/260N Under Tcca Counter IOC51 Timer/CounterUnder Tccb Counter IOC61 Under Tccc Counter IOC81 Comparator Related Tccx Status/Data Registers External Reference Signal Comparator Output Wake-up from Sleep Mode Using a Comparator as an Operation AmplifierComparator Interrupt Oscillator Modes OscillatorOscillator Modes Conditions Oscillator Type Crystal Oscillator/Ceramic Resonators CrystalFrequency C1pF C2pF External RC Oscillator Mode 18 Serial Mode Crystal/Resonator Circuit Diagram Cext Rext Average Fosc 5V, 25C Average Fosc 3V, 25C Internal RC Oscillator ModeInternal Drift Rate RC Frequency Temperature 40C ~ +85C 3V~5.5V Total External Power-on Reset Circuit Power-on ConsiderationsProgrammable WDT Time-out Period EM78P259N Residual Voltage ProtectionVdd EM78P260N Word Word1 Bit12 ~ Bit0 Code OptionCode Option Register Word Word Bit Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit Bit Microprocessor with OTP ROM Bit 3 HLP = Pulses equal to 8/fc s is regarded as signal= Pulses equal to 32/fc s is regarded as signal default Bit 2 ~ 0 PR2 ~ PR0 Protect Bits Instruction Set Bit 1 & Bit 0 RCM1, RCM0 RC mode selection bitsCustomer ID Register Word Instruction Binary Following are the EM78P259N/260N instruction setMnemonic Operation Status Affected Absolute Maximum Ratings Items Rating Symbol Parameter Condition Min Typ Max Unit DC Electrical CharacteristicsTa=25 C, VDD=5.0V±5%, VSS=0V Internal RC Drift Rate Voltage Min Typ Max AD Converter Characteristics Vdd=2.5V to 5.5V, Vss=0V, Ta=25C Device Characteristics Comparator OP CharacteristicsVdd = 5.0V, Vss=0V, Ta=25C Symbol Parameter Conditions Min Typ Max Unit AC Electrical CharacteristicTa=25C, VDD=5V±5%, VSS=0V AC Test Input/Output Waveform Timing DiagramsReset Timing CLK=0 TCC Input Timing CLKS=0 18-Lead Plastic Dual in line Pdip 300 mil Package TypePackage Information Package Type Pin Count Package Size 18-Lead Plastic Small Outline SOP 300 mil 838 Lead Plastic Shrink Small Outline Ssop 209 mil 650 Lead Plastic Dual-in-line Pdip 300 mil Lead Plastic Small Outline SOP 300 mil Address Trap Detect Quality Assurance and ReliabilityTest Category Test Conditions Remarks