Product Differences and Substitutes

My program is too large to fit in the uPD780034A, so I would like to switch over to the uPD780078.
Which parts of the program should I change?

Since a 16-bit timer has been added, the 16-bit timer related SFR names have been changed.
Add a "0" to the names, such as TMC0 -> TMC00 and CR01 -> CR010.

Regarding 3-wire serial, the number of SIO3 has been reduced to just 1, so remove "0" from SIO30 related SFR names, such as SIO30 -> SIO3.

Regarding SIO31, the function is completely changed from CSI1, so completely revise the program.

For the differences between the devices, refer to Comparison Chart (PDF 411KByte).

What are the uPD78P018F substitutes?
Also, are there any cautions I should be aware of regarding substitution?

In terms of functions, the uPD78F0078 is the substitute product.

However, the pin configuration and on-chip functions differ in part.
(Some additions and deletions have been made.)
Moreover, some SFR names differ, so these need to be revised.

There are also functions that require caution in how they are used (such as A/D functions), so if using these functions, the program must be changed.

For the differences between the devices, refer to Comparison Chart (PDF 411KByte).

What are the differences between the uPD780021AGC-AB8 and the uPD78P014GC-AB8?
(Pin configuration, software, etc.)

Please refer to APPENDIX A of the uPD780024A/34A User's Manual, which describes the differences between the 78014 Subseries and the 780034 Subseries.

In terms of functions, the major change has been an enhancement of the serial function, but the pin configuration is also completely different.

Also, the operation of the A/D converter has been changed partially.
As a subfamily, the 780034 Subseries has a flash memory product and not a PROM version.

For the differences between the devices, refer to Comparison Chart (PDF 411KByte).

What are the differences between the pin configuration, functions, and software of the uPD78058 and the uPD780058?

A comparison of these two devices can be found in APPENDIX A of the uPD780058 Subseries User's Manual.
(There are no other documents in particular that describe the differences between these two devices.)

Moreover, regarding detailed specification differences, please refer to each data sheet.
Regarding the pin configuration, there are the following differences.
(Functions have been added for pin 14 and pin 15.)

Pin No.	uPD78058	uPD780058
67	P06/INTP6	Vss0
74	AVDD	VDD0
14	P23/STB	P23/STB/TxD1
15	P24/BUSY	P24/BUSY/RxD1

Are there cautions I should observe regarding software when migrating from the uPD78058 to the uPD780058?

Regarding the uPD780058 Subseries, since there is a restriction that the accuracy of the first data following the start of A/D conversion is poor, the software must be changed for this part.

Also, since one port and external interrupt have been deleted, this part must be revised too.

Are there cautions I should observe when migrating from the uPD78P054GC to the uPD78F0058?

The major change in terms of functions is that P06/INTP6 has become Vss0.
But some of the functions related to Vdd and Vss also differ.

For example, the AVref0 pin now features an analog power supply function in addition to the existing A/D converter reference voltage.
Since the existing AVdd pin has become the power supply of the port block as Vdd0, caution is required for the wiring pattern.

Moreover, caution is also required for the power supply voltage range, which is a lower range of 1.8V to 5.5V.

The memory size differs.
Can this be resolved through memory size register manipulation?

Yes, the configuration can be made the same by setting the IMS register and the IXS register; but the program must also be revised.

In the uPD78F0058, since the accuracy of the first conversion result following the start of A/D conversion cannot be ensured, reading the first conversion result must be skipped.
Therefore, when using the A/D converter, the program must be changed.

What is the substitute for the uPD78P064GC?

The uPD78P0308GC can be used as a substitute product.

I plan to migrate from the uPD7805X to the uPD78005X; what kind of EMI noise countermeasures are implemented?

The following two major countermeasures are implemented for EMI noise.

When migrating from the uPD78238 to the uPD784038, are there cautions I should observe regarding address allocation, register usage, and the boot method?

Please observe the following points.

Addition of location specification

Please add the LOCATION instruction to the initial part of the program.

The stack pointer has been expanded from 16 bits to 24 bits.

MOVW must be changed to MOVG.

PSW has been expanded to 2 bytes, becoming PSWL and PSWH.

L/H specification is required for instructions other than PUSH and POP.

For interrupts, interrupt request flag registers have been eliminated.

Control has changed to control using the interrupt control register for each interrupt source.
(However, there is no problem when flag names such as "PIF0" are described.)
These points can be checked by the assembler.

The format of the PSW and MM registers has been changed.

Please revise the values set to these registers.

The vector addresses differ for each interrupt source.

Register indirect addressing

When "DE" and "HL" are described, they are treated as "TDE" and "WHL"; so if the W and T registers are not 0, a different address is specified.
At the beginning of the program, set WHL and TDE to 00XXXX.

Due to the expansion of the program space, the amount of data that is saved to the stack area has increased.

Check that there are no problems in the stack area.

The macro service control word allocation area differs.

The instruction length differs even for the same instruction.

Revision is required in the case of a program that takes into consideration the instruction length.

What are the differences in the instruction sets between the uPD78238 and the uPD784038?

Most of the instructions can be used without modification.

In 78K/2, a bank was set to P6 for external memory access (for example, MOV P6,#3) and MOV A,&!2000H was needed.
In 78K/4, please just describe MOV A, !!32000H without manipulating P6.
This results in the elimination of external memory specification with "&" as the operand address.

Regarding other instructions, the same instructions have the same function (although not exactly the same due to program space differences).

What are the differences between the uPD78F4216 and uPD78F4216A?

The differences between these two devices are the flash memory specifications, the fixing of bugs, and the improvement of characteristics.


(Due to these bug fixes, the compare register must be rewritten after stopping both timers in cascade connection mode.
When reading the compare register in the PWM mode, the value written to the master register is read.)

Are the cores of the uPD784216AY and uPD784038 the same?

Yes, they are the same 78K4 CPU cores.

In the uPD784031, what is the difference between items with (A) and items without (A) in the data sheet?

(A) suffixed to the part number indicates the quality grade; it does not denote any difference in functions.

What are the differences between the uPD784225 and uPD784038?

The uPD784038 is a pure 78K/4 Series device without relation to existing devices, whereas the uPD784225 is a limited-function version of the uPD784216 Subseries, which is a higher version of the 78K/0 Series of 8-bit microcontrollers.


The above are some of the typical differences between the PD784225 and uPD784038.

What are the differences between the uPD78F4938A and the uPD784938A?

The differences in the electrical characteristics between the mask version and the flash version include the following.


For details, refer to the data sheet.

Are the on-chip inverters in the uPD78984x and the uPD78495 the same?

No, they are not.
The inverter of the uPD78984x is for a 3-phase A/C servo.

What must be changed to switch from the uPD789114 to the uPD789114A?

The main changes are as follows.

(1) Modification for limitations
The following two limitations are modified.
- Limitation during input from Port 5
- Limitation on 10-bit A/D converter

(2) Improvement in operation speed
The maximum operating clock frequency is raised as follows.

What are the differences among the uPD78F9116, uPD78F9116A, and uPD78F9116B?

There are the following three main differences.

(1) Modification for limitations
The following two limitations are modified.
- Limitation on 10-bit A/D converter (uPD78F9116A and uPD78F9116B)
- Limitation during input from Port 5 (uPD78F9116B)

(2) Improvement in operation speed
The maximum operating clock frequency is raised as follows.

(3) Improvement in flash memory re-programming reliability

What must be changed to switch from the uPD78F9177 to the uPD78F9177A?

(1) Modification for limitations
The following limitation is modified.
- Limitation during input from Port 5

(2) Improvement in operation speed
The maximum operating clock frequency is raised as follows.


(3) Improvement in flash memory reliability
High-reliability versions (A) and (A1) are provided

I would like to use a 78K0/Kx1 device equipped with flash memory, but even for the same device there are six versions (uPD78F0138M1GC, uPD78F0138M2GC, uPD78F0138M3GC, uPD78F0138M4GC, uPD78F0138M5GC, and uPD78F0138M6GC), and I do not understand how to select one of these versions.

Among 78K0/Kx1 devices, various options can be specified as mask options, and a field following the product name has been added to indicate the correspondence of flash memory versions.

The two corresponding options are:


The M1 to M6 versions were added to incorporate various combinations of these option settings.

See the table below for these combinations:
The ways that these versions are used are summarized as follows.

(1)	When the minimum operation supply voltage is at least 4 V and a range from 2.7 V to 3 V is used, or when an external reset IC is used in combination, select version M1 or M2. - If the internal oscillator will not be stopped, select M1. For example, select uPD78F0138M1GC. - If the internal oscillator should be stopped, select M2. For example, select uPD78F0138M2GC.
(2)	When the minimum operation supply voltage is about 3 V, select version M3 or M4. - If the internal oscillator will not be stopped, select M3. For example, select uPD78F0138M3GC. - If the internal oscillator should be stopped, select M4. For example, select uPD78F0138M4GC.
(3)	When the minimum operation supply voltage is about 3.7 V, select version M5 or M6. - If the internal oscillator will not be stopped, select M5. For example, select uPD78F0138M5GC. - If the internal oscillator should be stopped, select M6. For example, select uPD78F0138M6GC.

What should I note when changing from the uPD78064 or uPD78064B Subseries to the uPD780308 Subseries?

The major functional difference is the addition of a 3-wire serial channel and internal expansion RAM. For details of differences between devices, see Comparison Table (to be prepared). Be sure to check the data sheet as there are also slight differences in electrical specifications.

I am considering using 8-bit microcontrollers, but there are so many different types (product names) that I do not know which one to choose. Could you provide a simple comparison chart?

A selection guide is available, so first refer to that. The selection guide can be viewed by inputting "78K Microcontrollers Selection Guide" in the search field on the top page of the NEC Electronics website, then clicking to go to the search results page, and selecting the Selection Guide from the list of PDFs displayed in the document search results field.

How should I choose an 8-bit microcontroller?

Specific functions are required for the realization of specific applications. Whether these required functions are incorporated on-chip is one of the judgment factors. To use an easy-to-understand example, if one wants to do something using a thermistor to detect temperatures, the need of an on-chip A/D converter for measuring the difference in potential between the two extremities of the thermistor is a judgment factor. If LCD display is required, whether to have the LCD controller on chip is a judgment factor. Further, if the amount of display data is large, combined use with an external display controller is called for, the availability of a communication function such as synchronous serial communication function (CSI) is a judgment factor. Whether to have a CAN on-chip, the functions of the on-chip timer, and the number of on-chip timers are all judgment factors.
Once judgment about the functions that are required has been made, study the required number of ports, ROM/RAM capacities, operating power supply voltage, processing speed (operating clock frequency), etc.
In the case of the latest 78K0 and 78K0S All Flash microcontrollers, the following letters in nicknames indicate the pin count (excerpt).

16-pin:	Y (for example, 78K0S/KY1+)
20-pin:	A (for example, 78K0S/KA1+)
30-pin:	B (for example, 78K0/KB2, 78K0S/KB1+)
44-pin:	C (for example, 78K0/KC2, 78K0/FC2)
52-pin:	D (for example, 78K0/KD2)
64-pin:	E (for example, 78K0/KE2, 78K0/LE2, 78K0/FE2)
80-pin:	F (for example, 78K0/KF2, 78K0/LF2, 78K0/FF2)
100-pin:	G (for example, 78K0/LG2)

Here, 78K0 and 78K0S indicate the CPU core that is used. K, L, and F after "/" indicate the application field. K = General purpose, L = LCD control, F = Automotive electronics (CAN available).

There are two cores for 8-bit All Flash microcontrollers, the 78K0 and 78K0S. How do they differ?

The 78K0S is a subset of the 78K0, from which a part of functions have been eliminated as a core. The main functions that have been eliminated as listed below. (Since the on-chip peripheral functions differ among the various microcontrollers, they are not covered here.)

• Register bank function
• Multiply-divide function (as instruction set)
• Decimal adjust function
• Interrupt priority level processing function
• Software interrupt function
• Nibble (4-bit) unit rotate function
• Boot swap function for internal flash self-programming

Moreover, the following instructions and addressings judged to be used infrequently, including instructions related to the above-listed eliminated functions, have been removed from the instruction set.

• Among 8-bit transfer and arithmetic instructions, "Based indexed addressing" (for example, MOV A, [HL+B] and ADD A, [HL+C]) has been deleted.
• Among 8-bit exchange instructions, "direct addressing" (XCH A, !addr16) have been deleted.
• Among 16-bit transfer instructions, access to the SFR area cannot be done (this has no impact, because no such SFR is mapped).
• Moreover, immediate data setting (MOVW saddrp, #word) for the short direct addressing (saddrp) area, and transfer (MOVW AX, !addr16, etc.) from/to AX register with direct addressing, have been deleted.
• In 8-bit operations, the destination register saving the operation result is restricted to the A register (instructions such as ADD C,A have been deleted).
• Multiply and divide instructions have been deleted.
• Rotate instructions for nibble (4-bit) units (ROR4 [HL], etc.) have been deleted.
• The decimal adjust instruction has been deleted.
  (If decimal adjustment is required, refer to Sample arithmetic operation program for CPUs that do not have a decimal adjust instruction in the FAQ.)
• With regard to bit manipulation, transfer and arithmetic instructions such as MOV1 CY,A.bit and AND1 CY,saddr.bit have been deleted.
• The CALLF instruction has been deleted.
• Instructions related to software interrupts have been deleted.
• The instruction for directly setting values to a stack pointer has been deleted. (This is handled by transfer from the AX register.)
• Register indirect addressing in bit judgment instructions (BT [HL].bit, $addr16, etc.) has been deleted.
• The semaphore control instruction (BTCLR instruction) has been deleted.
• The register bank selection instruction has been deleted.

In addition to the above, the 78K0 and 78K0S also differ in operation when another interrupt is received during an interrupt servicing (when multiple interrupts are not used). In the case of the 78K0, following return from an interrupt, one main processing instruction is executed and then the next interrupt servicing starts, but in the 78K0S, following return from an interrupt, the next interrupt servicing starts without executing a main processing instruction.

The 78K0 and 78K0S are available as 8-bit All Flash microcontrollers. They differ in pin count, but are there any other differences, and how are they used respectively?

The 78K0/Kx2 and 78K0S/Kx1+ are both 8-bit All Flash microcontrollers, but they employ different microcontroller cores. For the differences in core, refer to A3 of "Differences among 8-bit microcontroller products (78K0/78K0S)".
In addition to pin count (and thus port count) and core differences, there are also the following functional differences.

	78K0/Kx2	78K0S/Kx1+
Operating power supply voltage	1.8 to 5.5 V	2.2Note 1 to 5.5 V
Maximum operating frequency	20 MHz	10 MHz
ROM size	8 to 128 KB (Banks are used for 64 KB and above)	1 to 8 KB
RAM size	512 bytes to 7 KB (high-speed RAM: Up to 1 KB)	128 to 256 bytes (high-speed RAM only)
16-bit timer	1 or 2 channels	0 or 1 channel
8-bit timerNote 2	4 channels	1 or 2 channels
- Carrier generation	1 channel	None
Watch timer	Provided in some products	None
Buzzer output, clock output	Provided in some products	None
Watchdog timer	1 channel	1 channel
- Window function	Provided (4 stages)	None
- Illegal memory access detection	Provided	None
- Count clock	Fixed to low-speed internal oscillation clock	Low-speed internal oscillation clock or system clock
A/D converter (10 bits)	8 channels	None or 4 channels
Serial functions
- UART	2 channels	0 or 1 channel
- CSI	1 or 2 channels	None
- CSI with automatic transmit/receive function	Provided in some products	None
- I2C bus	1 channel	None
Key return interrupt	Provided in some products	None
Multiply-divide circuit	Provided in some products (16x16, 32/16)	Provided in some products (8x8)
POC	1.59 V or 2.7 V	Fixed to 2.1 V
Internal regulator	Provided	None
LVI	Power supply voltage/external pin	Power supply voltage only
Reset pin function	Reset pin	Reset/input port
System clock	Startup with high-speed internal oscillation clock, then selectable by program	Specified in option byte
Peripheral clock	System clock/high-speed internal oscillation clock	Selectable as a division of system clock
Flash memory
- Memory size specification function	Provided	None
- Programming with writer	UART/CSI	Use of X1 and X2
- Block size	1 KB	256 bytes
- Boot swap	Provided	None
- Mode control switching	Dedicated FLMD0 pin	Shared with X1
- Security function	Erase and rewrite are prohibited through specification with a security command or by the programming writer.	Erase and rewrite are prohibited with the protect byte.
- Self programming	Startup with FLMD0 pin	Startup with special sequence
Peripheral access arbitration	Arbitration with waits	None

Notes 1	:	Including POC voltage variation (2.0 to 2.2 V)
Notes 2	:	The supported timer functions differ.
Remark	:	This table lists only the main differences. For example, the source clocks that can be selected with the timer differ, the default state of the pins shared with analog input differ (analog input for 78K0/Kx2, digital input for 78K0S/Kx1+), and the various settings not listed in this table also differ. Moreover, there are also differences in characteristics: the accuracy of the high-speed internal oscillation clock is ±5% for the 78K0/Kx2 and ±5% (±3% when the temperature is restricted) for the 78K0S/Kx1+.

Select the appropriate product taking into consideration the required peripheral functions, processing speed, program size and future product expansion.