78K : 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]

78K : 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]

78K : 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)

78K : Timers, Counters

• 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]

78K : 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)

78K : 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]

78K : 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%)

78K : Difference between PPG output and PWM output

• Difference between PPG output and PWM output [contents common to all devices]

78K : CAN

• CAN settings


• About J1850 (CLASS 2) described in uPD780833Y

78K : 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]

78K : 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

78K : Other Peripheral Functions

• 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.

78K : 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]

78K : External Expansion

• How can external bus access be ascertained?


• External device expansion function

78K : Memory Allocation.. Directives, LOCATION

• 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]

78K : 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]

78K : Memory bank

• Memory bank (78K0/Kx2)

78K : 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?

78K : ROM Correction

• Details of ROM correction [78K0]

78K : Flash programming

See also "Common Items FAQ : 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]

78K : PROM Programming

• Conversion adapter compatibility (PA-78P078GF and PA-78208GF)


• uPD78P4038 programming adapter

78K : 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 ?

78K : 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?

78K : Pins..DC Characteristics, 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?

78K : 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?

78K : 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

78K : Product Differences and Substitutes

• 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+)

78K : 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]

78K : Packages

• Dry pack


• Package changes for the uPD78403x


• What is the uPD789316 package type?

78K : 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]

78K : Other..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?

78K : Reset Pin

• Using Reset Pin as Alternate-Function Port [Low-Pin-Count Device]

78K : Decimal calculations with microcontrollers (78K0, 78K0S, 78K0R)

• Decimal calculations with microcontrollers (78K0, 78K0S, 78K0R)

78K : Boot swap function

• Boot swap function (78K0/Kx2)

78K : 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.

78K : 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?

78K : 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?

78K : RX78K

• Do the 78K/0 and 78K/0S real-time-operating-system's conform to μITRON and other versions?

78K : Debug..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

78K : Development Tool Products

• How do PC-9800 and AT-compatible products differ?


• In what cases are the 78K4 tools required?