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Japan
All Questions List
A/D D/A conversion
- How to evaluate an 8-bit A/D converter using a flash device with a 10-bit A/D converter
- Developing a uPD780021A (8-bit A/D) program using the uPD78F0034A (10-bit A/D).
- 8-bit A/D conversion using uPD78F9116 [78K0/S]
- How is the 10-bit A/D conversion result input?
- High-speed 6-bit shift method for 10-bit A/D conversion result
- Description of conversion time in uPD789445 Preliminary Product Information
- Why do the A/D conversion times described in user's manuals and data sheets differ?
- Does A/D conversion end by the time specified by the ADM register?
- Can the pins not specified for analog input be used as ports?
- The A/D conversion results in the low-voltage region are not as expected.
- What problems are there when changing the A/D reference voltage AVref from 5V to 3.5V?
- Is the series resistor string cut off by ADCS0 = 0?
- What happens if I do not connect the dedicated A/D conversion power supply pins (AVDD and AVSS)?
- Is it not possible to obtain normal values unless the A/D conversion result is read twice?
- What are the set/reset conditions for the INTAD (A/D conversion end) interrupt flag?
- When using port pins as alternate function (A/D) pins, should the PM register setting be input or output?
- What is the A/D accuracy of the uPD780054?
- What is the A/D converter accuracy during low-voltage operation?
- Equivalent circuits of A/D converter
- How much is the impedance of an A/D input pin?
- What is the capacitance of capacitors that can be connected to the A/D pin?
- What is the maximum current that flows from the D/A converter's output pin?
- How to sample 8 analog inputs almost simultaneously [78K4]
- Conversion processing time [780034A Subseries]
- Reference voltage setting [780034A]
- Non-generation of A/D conversion end interrupt [All 78K]
- Conversion result that obtained is influenced by the result conversion. What was it caused? [78K0, 78K0S]
Clock
- How can I switch the instruction execution time?
- Clock frequency description (8.38MHz and 8.386MHz)
- Oscillation stabilization time
- Oscillation stabilization time 2 [All 78K]
- What is the subsystem clock oscillation stabilization time and how can it be checked?
- How do I switch from the subsystem clock to the main system clock?
- Can I connect the output of an external oscillator with a 3V power supply to the subsystem clock during 5 V operation?
- WTM is set even though the subsystem clock is not connected. Is this a problem?
- I cannot cancel HALT with a timer interrupt during subsystem clock operation.
- Does subsystem clock multiplication work even when the main system clock is stopped?
- Is the clock input to X1, X2 divided?
- How do I start watch interrupt servicing from the CPU stopped status?
- Minimum clock operation setting after reset
- I want use a low-frequency clock.
- Clock following stop release [78K0/Kx1]
- Clock monitor operation [78K0/Kx1]
- Clock output frequency error [All 78K]
- Stoppage of the main clock
- Stoppage of subsystem clock [All 78K0]
- Stoppage of clock [All]
- Clock switching [uPD780958]
- Is 2.5 V a suitable voltage for the X1 pin of the X1 oscillator? [78K0R/Kx3]
Serial Communication
- Concerning internal serial interface of microcontroller [common description]
- Selecting serial I/F [common information]
- Differences between synchronization and asynchronization for serial communication (common information)
- Handshake [common information]
- Serial buffer configuration [common information]
- Full-duplex/half-duplex communication [common information]
- Basic operation of asynchronous communication (contents common to almost all devices)
- Basic operation of 3-wire serial communication (contents common to almost all devices)
- Malfunction caused by settings of port that is alternate function of serial channel.
- Slave mode/master mode
- Unneeded data is sent at initial setting
- Initial setting method so that unneeded data is not sent
- How do I use the timer registers for the serial clock?
- Do the settings upon occurrence of an error affect INTSER0 ?
- Can I write the next transmit data after waiting for the time calculated from the baud rate?
- Settings when using SIO31 with the 2-wire serial interface
- Can ASCK2 be used as an I/O port when using the internal serial clock?
- PM1 mode settings
- What is the interval time when using an external clock?
- How can I eliminate variations in the time from transmit data write until transmission start?
- Is the difference between the nominal baud rate and actual baud rate a problem?
- Baud rate tolerance [78K/0, 78K/4]
- Procedure for 3-wire serial communication [All]
- Is it necessary to stop serial transmission/reception when switching the operation mode?
- Does communication not start unless data is read from SIO3 ?
- Repeated generation of reception completion interrupt if UART input pin remains low level
- Can the transmission speed be set to 600bps ?
- What is the handling when bit displacement occurs due to a clock anomaly during synchronous communication?
- Is the SCK1 pin (P22) initial output value H or L ?
- How can I set the baud rate to 4800bps when the clock is 12.5 MHz ? [78K/4]
- Calculation of baud rate when TO1 is selected [78K/4]
- Recovery processing when transmission is disabled during transmission
- Cautions related to serial communication settings
- Support for SPI
- 3-wire serial operation [contents common to all devices]
- Support of 300 bps when using UART [All 78K0]
- Relationship between the data length and the existence of parity
- Normal data cannot be received during serial communication.
- Can the 3-wire serial clock be started from L ?
- Settings when using serial function (differences between 78K/0 and 78K/4)
- When not using an external clock, can I use the ASCK pin as a port? [78K/4]
- Usage of Serial Interface with Automatic Transmit/Receive Function (CSIA0) [78K0/Kx]
- Support for Microwire (common to almost all devices that include CSI)
- How to use Serial Array [78K0R]
- How to use UART6 which included 78K0/Kx2, when it is to be connected with RS-232C? [78K0, 78K0S]
- How is the control signal processed although there is no Clear To Send signal of UART built-in the microcotroller? [Common]
- Internal UART doesn't have enough function. How can I construct UART using the general port instead? [78K0, 78K0S Common]
- Programming example (No.1) for using UART [78K0S Common]
- Programming example (No.2) for using UART [78K0S Common]
- Even if read out SIO1n,is't there any method which the following clock does not output? [78K0/Kx Common]
Timer Counter
- Can the inverter control timer be used for interval timer interrupts?
- I want to permanently stop timer outputs TO70 to TO75.
- Timer wait without using interrupts
- How large is the count clock error?
- The external event counter does not respond.
- Interrupt control when generating interrupts by inputting timer output to a different timer
- Description of capture function limitations
- The initial counter value becomes 1.
- Inversion of ON and OFF times in PPG output [All 78K0 and 78421x]
- No PPG output [All 78K0]
- 16-bit timer interval [78K0S]
- Interrupt at overflow of 16-bit timer [Most 78K0, 78K0S]
- Reading 16-bit timer [78K0]
- PWM output using 8-bit timer [All 78K0]
- Timer output frequency not as expected [All]
Watchdog Timer
- What is the count clock of the watchdog timer?
- Can I clear the watchdog timer during timer interrupt servicing?
- Operand error recovery processing [78K/4]
- Branch processing at power-on. (Returning the interrupt function to the initial setting.)
- What is the restoration time when the reset signal is generated after watchdog timer overflow?
- Can the watchdog timer mode be set after the watchdog timer has been used as an interval timer?
- Is reset by the watchdog timer the same as the reset signal?
- Can the watchdog timer operation be stopped and started by program?
- What is the watchdog timer operation when the STOP mode is released?
- Does the watchdog timer count during the clock oscillation stabilization time?
- Initialization from watchdog interrupt [78K0]
- Servicing of watchdog timer interrupt [78K0, 78K0S]
- Clearing/starting the watchdog timer [All]
- Mode upon watchdog timer overflow [All]
- Using watchdog timer (78K0/Kx2)
Interrupts
- Basic operations of interrupt service
- Multiple acknowledgment of same interrupt [78K0]
- Multiple interrupt processing method
- Interrupt mode settings during remote control reception using TM0 in free-running mode
- No interrupt is acknowledged during interrupt flag wait.
- Case when a different interrupt occurs during operation with the subsystem clock
- Clock when interrupt occurs during HALT using subsystem clock
- Can interrupts be acknowledged immediately after reset?
- What do I need to do to write an interrupt request flag in the IF0L register without clearing other flags?
- Is an interrupt pulse width valid even if it is shorter than the rating?
- At which timing interval is external interrupt processing performed?
- I want to branch to power-on processing (initialize the interrupt function).
- I want to receive 1 byte using the macro service of the CSI. [78K/4]
- Acknowledgment of interrupt request during macro service execution [78K4]
- Does macro service execution affect the operation of the main program? [78K/4]
- How can I use the macro service with C language? [78K/4]
PWM
- 14-bit PWM output cycle and pulse width using timer 0 (Basic items)
- What is the value set to PWMn when not using PWM?
- Setting PWM output to a low level (as PWM 0%)
Difference PPG and PWM
CAN
I2C Bus
- Overview of I2C bus
- What is the I2C bus pull-up resistance?
- Is there a problem if I set STT0 and SPT0 at the same time in the initial settings for the I2C bus?
- Example of controlling external EEPROM via I2C bus (for master)
- Cannot start I2C bus [78K family]
- Difficulties in controlling the I2C bus [Common]
- I2C's clock frequency differs from set value [Common]
- I was able to read the EEPROM without any problem, but have trouble issuing a start condition afterward [Common]
- What is the simplified I2C? [common to 78K0R]
LCD
- LCD controller/driver on MCU
- Can an LCD voltage of 3V be obtained when VDD = 5V in the LCD driver?
- What is the LCD dividing resistor value?
- What is the meaning of VAON0 in the LCDM0 register?
- Value and connection of external capacitor for LCD connection
Other Peripheral Func
- Control of real-time output ports
- Buzzer output procedure
- What are the differences between INT0 to INT3 in the uPD780021A ?
- If timer/counter 1 output is prohibited, can P31 be used as a port? [78K/4]
- Setting of TOE1 of TMC1 register [78K/4]
- Which SFR specifies external wait for the wait function? [uPD78P4038]
- Can both external wait and internal wait be enabled?
- Effective timing of external input wait signal
- Can I/O ports and external interrupts be mixed in the same port?
- Port mode and port data settings when using alternate functions of port
- Does a Schmitt trigger input pin work as a Schmitt trigger input in the case of normal ports as well as in the case of alternate functions?
- uPD78932x ports [78K0/S]
- An SFR illegal break occurs when standby is released.
- Does the uPD789166 have a comparator? [78K/0S]
- The input port cannot be normally read immediately after setting internal pull-up.
Execution Time
- The instruction execution time is different from the time indicated in the manual.
- SUBW instruction execution clock count [78K/4]
- Why are there several types of instruction execution times? [78K/4]
- When there are several instruction byte counts, which should be used? [78K/4]
- Which is the fastest 78K/4 device? [78K/4]
- How many bytes long is the instruction queue? [78K/4]
- Can the instruction queue status be ascertained? [78K/4]
External Expansion
Memory Allocation
- Can variables and code be assigned to memory outside of ordinary memory?
- The message "F206: Segment xxxxxx can't allocate to memory - ignored" is output when linking.
- Using a device with built-in ROM as external ROM
- Operation of MOV A, [HL] at LOCATION 0H [78K4]
- Must 24-bit instructions be set in order to access RAM for LOCATION 0FH? [78K4]
- MOV instruction that does not affect T registers with LOCATION 0H [78K4]
- Characteristics of LOCATION 0H and LOCATION 0FH [78K4]
- Is the base area from 0 to FFFF or from 0 to 1FFFF? [78K4]
- When changing a 78K4 device's link directive, must RAM include an SFR area?
- Must word data be aligned to even-numbered addresses? [78K4]
- How is word data stored in memory?
- Where are registers mapped? [78K0S]
- Using the CALLT area as a program area
- RAM area pointed to by 16-bit stack pointer [78K0R]
Memory
- External memory expansion
- External memory access timing
- I want to connect SRAM.
- Internal RAM data hold voltage
- Is program execution possible using internal high-speed RAM? [78K/0]
- External memory access method [78K/4]
- Data read timing [78K/4]
- Internal EEPROM of microcontroller [common to uPD78986x]
Memory Bank
ROMization
- Fill characters used for unused areas of ROM
- Is it possible to fill unused areas in ROM with a certain value?
- What device file should be used when mass-producing a mask-ROM version after developing with a flash memory version?
- Can the IMS (memory size switching register) settings be left as they are when mass-producing mask-ROM version?
- When developing with a flash memory version, is there any problem if the IMS register is set so as to specify a memory size different from that in the final target mask-ROM version?
- What is the -R option for OC78K?
ROM Correction
Flash Programming
- Can the FLSPM0 settings for the flash version be omitted?
- Is onboard programming firmware literature available?
- What is the method to stop programming when a malfunction occurs?
- What about pull-up of UART pins during flash programming?
- Is it a problem if the VPP rise time is slow?
- Can a pull-down resistor be connected to the VPP pin?
- What is a suitable CPU clock for flash programming?
- What tools are there for on-board programming of flash memory?
- What is the VPP switching method during on-board programming?
- What is the flash rewrite count?
- Conditions of VDD power supply current of flash memory programming characteristic [78K0/Kx2, 78K0/Lx2]
PROM Programming
Power Supply
- Separation of A/D power supply from that of digital circuit
- What is the minimum operation guaranteed voltage and data hold voltage?
- Is AVDD required for power supply backup?
- Are power supply pins connected internally?
- Power supply voltage range
- Is the power supply current at reset the same as the current in STOP mode?
- Reduced value of operating current in low-power mode
- What is the power supply variation tolerance?
- I want to apply a voltage to ports externally when the power is off.
- Is it possible to supply different power supplies to VDD0 and VDD1 ?
- Does VDD mean VDD0 ? or VDD1 ?
Reset
- What is the port status when the reset signal is input in the oscillation stopped status? [78K0]
- What is needed to forcibly execute reset processing?
- Program loop occurs when the power supply is applied gradually.
- Is it OK if the reset input time is long?
- The LEDs connected to the ports light upon reset.
- Is the RAM data held when reset is applied?
- Can reset be used to release the STOP mode?
DC Chara Pin Handling
- DC characteristics of output pins
- DC characteristics when VDD is less than 4.5V
- Can an on-chip pull-up resistor be switched on when using a mixture of input and output ports?
- How is the FIP port used?
- Handling of unused pins
- Can unused pins be left open in the output mode?
- Can unused pins be connected to VDD0 or VSS0 using a common resistor?
- What is the maximum output current of ports that can drive LEDs directly?
- Why are open-drain pins connected to VDD and not VSS when they are not used?
- Input protection diode
- Can pull-up resistors be specified by a mask option?
- uPD789407 damage
- Handling of test pins. Can these pins be pulled down with a 10kΩ resistor?
Oscillation
- What is the resistance of the oscillator?
- What is the capacitance of the external capacitor when Ceralock is used with the uPD78P4038?
- uPD78F4216A resonator
- uPD784218A resonator
- uPD78F4216A oscillation frequency variation
- Can XT1 be connected to GND?
- Is an external resistor required for the oscillator?
- Detection of stabilized oscillation
- Is it necessary to wait for the oscillation to stabilize when returning from the IDLE mode?
- Time until oscillation stop after reset input
- What happens when the feedback resistor is not used?
Noise
- Is noise influence easily received when XT1 is set to open?
- What noise countermeasures are implemented in LSI devices?
- The harmonic of the power supply current differs from the clock frequency. [78K0]
- Does noise immunity differ between one-time PROM products and mask ROM products?
- Differences between uPD78F0034A and uPD78P018F in noise resistance of interrupt request pins
Product Differences
- Cautions when migrating from uPD780034A to uPD780078
- uPD78P018F substitute
- What are the differences between uPD780021A and uPD78P014?
- What are the differences between uPD78058 and uPD780058?
- What are the differences between uPD78P054 and uPD78F0058?
- What is the substitute for uPD78P064GC?
- What are the differences in noise countermeasures between uPD7805X and uPD78005x?
- What are the differences between uPD78238 and uPD784038?
- What are the differences between uPD78F4216 and uPD78F4216A?
- Are the cores of uPD784216AY and uPD784038 the same?
- Regarding uPD784031(A)
- What are the differences between uPD784225 and uPD784038?
- What are the differences between uPD78F4938A and uPD784938A?
- What are the differences between uPD78984x and uPD78495?
- What are the differences between the uPD789114 Subseries and the uPD789114A Subseries?
- What are the differences between the uPD78F9177 and the uPD78F9177A?
- Product names of flash memory versions [78K0/Kx1]
- Differences Between uPD78064, uPD78064B, and uPD780308 Subseries
- Differences among 8-bit microcontroller products (78K0/78K0S)
- Differences between 78K0/Kx2 and 78K0S/Kx1+ (78K0/Kx2, 78K0S/Kx1+)
Ratings
- Differences between absolute maximum ratings and DC characteristics
- Power supply voltage and operating frequency range
- Can the high-speed mode be used with VDD = 1.8V ? [78K/0S]
Packages
Programming
- Processing to be executed first [common to 78K]
- Sample arithmetic operation program for CPUs that do not have a decimal adjust instruction
- Safety measures when unused interrupt occurs
- Approach to register bank allocation
- LCD display RAM bit set/reset
- Port bit clearing
- Instruction for substituting a value for the stack pointer [78K/0S]
- Is there a need to differentiate between uppercase and lowercase for the CC78K0 ?
- What cautions apply when programming beyond 10000H ? [78K/4]
- Can setting-type registers be rewritten using a fixed cycle?
- Table access in 16-bit space
- The read value differs from the one set to the stack point. [78K0/Kx1, 78K0S]
Prohibited Items
- What happens when a prohibited value is set to a register?
- What happens when an undefined instruction is executed during inadvertent program loop?
- Is it all right to read an SFR area to which registers have not been allocated?
Reset Pin
Decimal calculations
Boot swap function
RA78K
- An error occurs when the bit SFR name is used.
- Multiple CSEG in one include file
- The message "F104 Illegal library file -- different target chip" is output by the librarian.
- The message "not enough space for environment" is output when RA78Kx is started. [RA78Kx (16-bit version)]
- Output of the saddrp2 code, which has a short instruction length [RA78K4]
- Symbol definition options for the assembler
- Assemble error F325 is output at location 0H. [RA78K4]
- Can a library be created?
- Include file name for RA78K0S
- The message "A102 Illegal processor type specified" is output.
- An error is output at $ PROCESSOR for RA78K0S.
- Conventional memory required for assembly
- I want to execute A-(-10).
- An error occurs when IEBus-related register names are used with RA78K.
CC78K
- F861 No EXT_TABLE specifier is output.
- The startup routine settings dialog box is dimmed out and settings cannot be performed.
- It looks like 0x0080 gets sign extended.
- What is the output file name setting method?
- How can re-start from the same address after a reset of the CC78K0?
- Is there a way to place function entities in the definition sequence?
- I want to place a program in the gap area. [CC78K0]
- How are bits specified in the various registers of SFR?
- Securing interrupt stack with compiler
- How are macro services used in the C language?
- What is the result value when the floating-point calculation overflows?
- What is the result value when division by 0 is performed during floating-point division?
- What is the maximum value that can be returned for divisions (fdiv) in floating-point division?
- Are double-precision floating points supported? [CC78K4]
- An error occurs with the external declaration of an external array variable.
- Saving the work area during interrupts
- Re-entrant characteristics of library function [CC78K4]
- The message "ERROR F304 Operand out of range" is output when a 24-bit address space is accessed. [CC78K4]
- The message "A402 File has no string table for symbol" is output during linking.
- The message "F304 Operand out of range " is output during linking.
- The message "F405 Undefined symbol '@@xxxx'" is output several times during linking.
- The message "F112 Too much internal node on temporary file" is output when the program amount increases.
- The link error "Segment @@RTARGO can't allocate to memory" is output when the CC78K version is upgraded.
- The link error "W417 The version of RA78K in file xxxxxx are more than one" is output when the CC78K version is upgraded.
- A link error is output when the CC78K version is upgraded. (@@RTARG0 area mapping)
- Must 78K/4 link directive changes include the SFR area in RAM?
- The error message "F702 Too many callt function" is output when the CC78K version is upgraded.
- Do the compiler products include an assembler?
SM78K
- SM78Kx pin monitor
- How can multiple source windows be opened with SM78Kx ?
- There are items for which the SFR display of SM78Kx does not change.
- How can the communication functions be simulated with the simulator?
RX78K
IE ID Socket
- What are the differences between the ICE and the actual device? (mask option resistance, etc.)
- Memory mapping in configuration dialog box at debugger startup
- How is stack-over detected with the ICE?
- The message "Could not find PC location line information" is displayed during step operation.
- Real-time RAM sampling function usage method
- I cannot set breaks in the ID78K4 source window.
- A non-map break occurs upon program execution.
- The message "0600(A); Internal Error" is output at ID78K0S startup.
- The message "0106(A); Anomaly in receive data" is output when trying to start up ID78K0-NS.
- OSMS of IE-78K0
- The message "0100(F) Communication with in-circuit emulator not possible." is output when JP7 of IE-78K0 is set.
- Is it possible to place a resonator on the parts board of the IE-780908-R-EM?
- What is the required equipment configuration for using IE-78K0-NS?
- uPD780022 development tools
- What are the differences between IE-78K4-NS and IE-784000-R?
- What does the "-A" in IE-78K0S-A mean?
- Pattern diagrams for uPD784216 sockets
- IE-78K4-NS socket of uPD784216
- Support for MI-78K0S (mini ICE)
- NW-78KOH, ND-941
Tool Products
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