EMC EM78P451WM

EM78P451
8-Bit Microcontroller
with OTP ROM
Product
Specification
DOC. VERSION 1.1
ELAN MICROELECTRONICS CORP.
June 2003
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are trademarks of ELAN Microelectronics Corporation.
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Contents
Contents
1
2
3
4
GENERAL DESCRIPTION ................................................................................................... 1
FEATURES........................................................................................................................... 1
PIN ASSIGNMENT ............................................................................................................... 2
FUNCTION DESCRIPTION.................................................................................................. 4
4.1
Operational Registers ..................................................................................................4
4.1.1
4.1.2
4.1.3
4.1.4
4.1.5
4.1.6
4.1.7
4.1.8
4.1.9
4.1.10
4.1.11
4.1.12
4.1.13
4.1.14
4.1.15
4.2
R0 (Indirect Address Register) ......................................................................................4
R1 (TCC) .......................................................................................................................4
R2 (Program Counter) & Stack......................................................................................4
R3 (Status Register) ......................................................................................................6
R4 (RAM Select Register) .............................................................................................6
R5~R8 (Port 5 ~ Port8)..................................................................................................6
R9 (Port9) ......................................................................................................................7
RA (SPIRB: SPI Read Buffer)........................................................................................8
RB (SPIWB: SPI Write Buffer).......................................................................................8
RC (SPIS: SPI Status Segister).....................................................................................8
RD (SPIC: SPI Control Register)...................................................................................9
RE (TMR1: Timer1 register) ..........................................................................................9
RF (PWP: Pulse width preset register)........................................................................10
R20~R3E (General Purpose Register)........................................................................10
R3F (Interrupt Status Register) ...................................................................................10
Special Purpose Registers .........................................................................................10
4.2.1
4.2.2
4.2.3
4.2.4
4.2.5
4.2.6
4.2.7
A (Accumulator) ...........................................................................................................10
CONT (Control Register) .............................................................................................10
IOC5 ~ IOC9 (I/O Port Control Register)..................................................................... 11
IOCC (T1CON: Timer1 Control Register).................................................................... 11
IOCD (Pull-high Control Register) ...............................................................................12
IOCE (WDT Control Register) .....................................................................................12
IOCF (Interrupt Mask Register) ...................................................................................13
4.3
TCC/WDT Presacler ..................................................................................................14
4.4
I/O Ports .....................................................................................................................15
4.5
SERIAL PERIPHERAL INTERFACE MODE ..............................................................17
4.5.1
4.5.2
4.5.3
4.5.4
4.5.5
4.5.6
4.6
Overview & Features ...................................................................................................17
SPI Function Description .............................................................................................19
SPI Signal & Pin Description .......................................................................................20
Programmed the Related Registers ............................................................................22
SPI Mode Timing .........................................................................................................24
Software Application of SPI .........................................................................................25
Timer 1 .......................................................................................................................29
4.6.1
4.6.2
Overview......................................................................................................................29
Function Description....................................................................................................30
Product Specification (V1.1) 06.30.2003
• iii
Contents
4.6.3
4.7
Programmed the Related Registers ............................................................................30
RESET and Wake-up .................................................................................................31
4.7.1
The Status of RST, T, and P of STATUS Register .......................................................36
4.8
Interrupt......................................................................................................................36
4.9
Oscillator ....................................................................................................................37
4.9.1
4.9.2
4.9.3
Oscillator Modes..........................................................................................................37
Crystal Oscillator/Ceramic Resonators (XTAL) ...........................................................38
RC Oscillator Mode .....................................................................................................39
4.10 Code Option Register.................................................................................................41
4.11 Instruction Set ............................................................................................................42
5
6
4.12 Timing Diagrams ........................................................................................................45
ABSOLUTE MAXIMUM RATING ....................................................................................... 46
ELECTRICAL CHARACTERISTICS .................................................................................. 46
6.1
7
DC Characteristic .......................................................................................................46
6.2 AC Characteristic .......................................................................................................47
Application Circuit ............................................................................................................ 48
APPENDIX
A
Package Types .................................................................................................................. 49
Specification Revision History
iv •
Doc. Version
Revision Description
1.0
Initial version
1.1
Change Power on reset content
Date
2003/06/30
Product Specification (V1.1) 06.30.2003
EM78P451
8-Bit Microcontroller with OTP ROM
1
GENERAL DESCRIPTION
The EM78P451 is an 8-bit microprocessor designed and developed with low-power,
high speed CMOS technology. Its operational kernel is implemented with RISC-like
architecture and is available in the mask ROM version. The one time programmable
(OTP) version is flexible, both in mass production or engineering test stages. OTP
provide users with unlimited volume with favorable price opportunities. This device is
equipped with the Serial Peripheral Interface (SPI) function and an easy-implemented
RS-232. The EM78P451 is very suitable for wired communication. Only 58
easy-to-learn instructions are needed and user’s program can be emulated with EMC
In-Circuit Emulator (ICE).
2
FEATURES
Operating voltage range: 2.3V~5.5V.
Operating temperature range: 0°C~70°C.
Operating frequency rang (base on 2 clocks ):
• Crystal mode: DC~20MHz at 5V, DC~8MHz at 3V, DC~4MHz at 2.3V.
• RC mode: DC~4MHz at 5V, DC~4MHz at 3V, DC~4MHz at 2.3V.
Low power consumption:
• Less then 3 mA at 5V/4MHz
• Typically 10 µA during sleep mode
Serial Peripheral Interface (SPI) available.
4K × 13 bits on chip ROM (EM78P451).
11 special function registers.
140× 8 bits on chip general-purposed registers.
5 bi-directional I/O ports (35 I/O pins).
3 LED direct sinking pins with internal serial resistors.
Built-in RC oscillator with external serial resistor, ±10% variation.
Built-in power-on reset.
5 stacks for subroutine nesting.
8-bit real time clock/counter (TCC) with overflow interrupt.
Two machine clocks or four machine clocks per instruction cycle.
Power down mode.
Product Specification (V1.1) 06.30.2003
(This specification is subject to change without further notice)
•1
EM78P451
8-Bit Microcontroller with OTP ROM
Programmable wake up from sleep circuit on I/O ports.
Programmable free running on-chip watchdog timer.
12 wake-up pins.
2 open-drain pins.
2 R-option pins.
32 programmable pull-high input pins.
Packages:
• 40 pin DIP 600mil: EM78P451P.
• 44 pin QFP: EM78P451AQ.
Four types of interrupts.
•
•
•
•
SPI transmission completed interrupt.
TCC overflow interrupt.
Timer1 comparator match interrupt.
S C K /P 9 4
9
S S /P 9 5
10
P 50
11
P 51
12
P 52
13
P 53
32
P 65
31
P 64
30
P 63
29
P 62
28
P 61
14
27
P 60
P 54
15
26
P 87
P 55
16
25
P 86
P 56
17
24
P 85
P 57
18
23
P 84
P 80
19
22
P 83
P 81
20
21
P 82
P90
P91
S D I/P 9 2
S D O /P 9 3
S C K /P 9 4
S S /P 9 5
P50
P51
P52
P53
P54
NC
NC
NC
P70
36
35
34
VDD
38
37
R-OSCI
39
1
33
2
32
3
31
4
30
5
29
EM 78P451AQ
6
28
7
27
8
26
9
25
10
24
11
23
P71
P72
P67
P66
P65
P64
P63
P62
P61
P60
P87
22
P 66
P86
33
P85 21
8
P84 20
P 67
S D O /P 9 3
P83 19
P 72
34
17
35
7
P55 12
6
S D I/P 9 2
P82 18
P 91
P 70
NC
P 71
VSS
36
O SCO
5
40
P 90
V D D
41
37
P80 15
4
P81 16
C L K
DATA
38
INT
3
42
R -O S C I
D A T A
P57 14
O S C O
39
CLK
40
2
43
1
IN T
P56 13
V S S
44
PIN ASSIGNMENT
EM78P451P/W M
3
External interrupt (/INT).
Fig. 1 Pin Assignment
2•
Product Specification (V1.1) 06.30.2003
(This specification is subject to change without further notice)
EM78P451
8-Bit Microcontroller with OTP ROM
Table 1 Pin description
Symbol
Pin No.
Type
Function Description
R-OSCI
39
I
■ In XTAL mode: Crystal input; In internal C, external R mode: 56Kohm±5% pull
high for 1.8432MHz.
OSCO
40
O
■ In XTAL mode: Crystal output; In RC mode: Instruction clock output.
P90~P95
5~10
I/O
P80~P87
19~26
I/O
P70~P72
37~35
I/O
CLK
4
I/O
DATA
3
I/O
P60~P67
27~34
I/O
P50~P57
11~18
I/O
VDD
38
-
■ Power supply pin.
VSS
1
-
■ Ground pin.
■ An interrupt schmitt-triggered pin.
■ The function of interrupt triggers at the falling edge.
■ Users can enable it by software. The internal pull-up resistor is around 50K
ohms.
■ General bi-directional I/O port. All of its pins can be pulled-high by software.
P90 and P91 are pin-change wake up pins.
■ General bi-directional I/O port. All of its pins can be pulled-high by software.
P80 and P81 are also used as the R-option pins.
■ LED direct-driving pin with internal serial resistor used as output and is software
defined.
■ By connecting P74 and P76 together.
■ P74 can be pulled-high by software and it is also a pin-change wake up pin.
■ P76 can be defined as an open-drain output.
■ By connecting P75 and P77 together.
■ P75 can be pulled-high by software and it is also a pin-change wake up pin.
■ P77 can be defined as an open-drain output.
■ General bi-directional port. All of its pins can be pulled-high by software, and
pin-change wake up pins.
■ General bi-directional I/O port. All of its pins can be pulled-high individually by
software.
/INT
2
I
SDI
7
I/O
■ Serial data in for SPI.
SDO
8
I/O
■ Serial data out for SPI.
SCK
9
I/O
■ Serial clock for SPI.
/SS
10
I/O
■ /Slave select for SPI.
Product Specification (V1.1) 06.30.2003
(This specification is subject to change without further notice)
•3
EM78P451
8-Bit Microcontroller with OTP ROM
4
FUNCTION DESCRIPTION
W DT Tim er
W DT
Tim e-out
PC
STACK 1
STACK 2
Prescaler
STACK 3
Oscillator/
Tim m ing
Control
/ INT
STACK 4
ROM
STACK 5
Interrupt
Control
R1(TCC)
Sleep
&
W ake Up
Control
Instruction
Register
ALU
Instruction
Decoder
RAM
R3
ACC
TM R1
R4
DATA & CONTROL BUS
IOC5
R5
IOC6
R6
IOC7
R7
PPPPPPPP
55555555
01234567
PPPPPPPP
66666666
01234567
P
7
0
P
7
1
IOC9
R9
IOC8
R8
P PP P
9 9 9 9
0 1 2 3
/ /
S S
DD
I O
PPPPPPPP
88888888
01234567
P
7
2
P
9
4
/
S
C
K
SPI
ENGIN
P
5
5
/
/
S
S
Fig. 2 Functional Block Diagram
4.1 Operational Registers
4.1.1 R0 (Indirect Address Register)
R0 is not a physically implemented register. It is used as an indirect addressing
pointer. Any instruction using R0 as register actually accesses data pointed by the
RAM Select Register (R4).
4.1.2 R1 (TCC)
Increased by the instruction cycle clock.
Written and read by program as any other register.
4.1.3 R2 (Program Counter) & Stack
R2 and the hardware stacks are 12 bits wide.
The structure is depicted in Fig. 3.
Generates 4K × 13 on-chip ROM addresses to the relative programming instruction
codes. One program page is 1024 words long.
All the R2 bits are set to "1"s as a RESET condition occurs.
"JMP" instruction allows direct loading of the lower 10 program counter bits. Thus,
"JMP" allows jump to any location on one page.
4•
Product Specification (V1.1) 06.30.2003
(This specification is subject to change without further notice)
EM78P451
8-Bit Microcontroller with OTP ROM
"CALL" instruction loads the lower 10 bits of the PC, and then PC+1 is pushed into
the stack. Thus, the subroutine entry address can be located anywhere within a
page
"RET" ("RETL k", "RETI") instruction loads the program counter with the contents
at the top of stack.
"MOV R2, A" allows the loading of an address from the "A" register to the lower 8
bits of PC, and the ninth and tenth bits (A8~A9) of PC are cleared.
"ADD R2, A" allows a relative address be added to the current PC, and the ninth
and tenth bits of PC are cleared.
Any instruction that is written to R2 (e.g. "ADD R2, A", "MOV R2, A", "BC R2,6",⋅⋅⋅⋅⋅)
(except "TBL") will cause the ninth and tenth bits (A8~A9) of PC to be cleared.
Thus, the computed jump is limited to the first 256 locations of any program page.
"TBL" allows a relative address be added to the current PC (R2+A→R2), and
contents of the ninth and tenth bits (A8~A9) of PC are not changed. Thus, the
computed jump can be on the second (or third, 4th) 256 locations on one program
page.
In case of EM78P451, the most significant bits (A10~A11) will be loaded with the
contents of bits PS0~PS1 in the status register (R3) upon the execution of a "JMP",
"CALL", or any other instructions which writes to R2.
All instructions are single instruction cycle (fclk/2 or fclk/4) except for the instruction
that would change the contents R2. Such instruction will need one more instruction
cycle.
CALL
PC
A11A10
00
A9A8
000
3FF
01
400
7FF
A7
~ A0
Stack 1
RET
Stack 2
RETL
Stack 3
RETI
Stack 4
Stack 5
Page 0
001:Hareware interrupt location
Page 1
002:Software interrupt (INT instruction) location
FFF:Reset location
10
800
11
C00
BFF
FFF
Page 2
Page 3
Fig. 3 Program Counter Organization
Product Specification (V1.1) 06.30.2003
(This specification is subject to change without further notice)
•5
EM78P451
8-Bit Microcontroller with OTP ROM
4.1.4 R3 (Status Register)
7
6
5
4
3
2
1
0
GP
PS1
PS0
T
P
Z
DC
C
Bit 0 (C) Carry flag
Bit 1 (DC) Auxiliary carry flag
Bit 2 (Z)
Zero flag. Set to "1" if the result of an arithmetic or logic operation is zero.
Bit 3 (P)
Power down bit. Set to 1 during power on or by a "WDTC" command and
reset to 0 by a "SLEP" command.
Bit 4 (T)
Time-out bit. Set to 1 with the "SLEP" and the "WDTC" commands, or
during power up and reset to 0 with WDT timeout.
Bits 5 (PS0) ~ 6 (PS1) Page select bits. PS0~PS1 are used to pre-select a program
memory page. When executing a "JMP", "CALL", or other instructions
which causes the program counter to be changed (e.g. MOV R2, A),
PS0~PS1 are loaded into the 11th and 12th bits of the program counter
where it selects selecting one of the available program memory pages.
Note that RET (RETL, RETI) instruction does not change the PS0~PS1
bits. That is, the return will always be to the page from where the
subroutine was called, regardless of the current setting of PS0~PS1 bits.
PS1 bit is not used (read as "0") and cannot be modified in EM78P451.
PS1
PS0
Program memory page [Address]
0
0
Page 0 [000-3FF]
0
1
Page 1 [400-7FF]
1
0
Page 2 [800-BFF]
1
1
Page 3 [C00-FFF]
Bit 7 (GP) General read/write bit.
4.1.5 R4 (RAM Select Register)
Bits 0~5 are used to select the registers (address: 00~3F) in the indirect addressing
mode.
Bits 6~7 determine which bank is activated among the 4 banks.
If no indirect addressing is used, the RSR is used as an 8-bit general-purposed
read/writer register.
See the configuration of the data memory in Fig. 4.
4.1.6 R5~R8 (Port 5 ~ Port8)
Four general 8 bits I/O registers
Both P74 and P76 read or write data from the DATA pin, while both P75 and P77 read
or write data from the CLK pin.
6•
Product Specification (V1.1) 06.30.2003
(This specification is subject to change without further notice)
EM78P451
8-Bit Microcontroller with OTP ROM
4.1.7 R9 (Port9)
A general 6-bit I/O register. The values of the two most significant bits are read as "0".
00
R0
01
R1 (TCC)
02
R2 (PC)
STACK 0
03
R3 (Status)
STACK 1
04
R4 (RSR)
STACK 2
05
R5 (Port 5)
STACK 3
IOC5
06
R6 (Port 6)
STACK 4
IOC6
07
R7 (Port 7)
IOC7
08
R8 (Port 8)
IOC8
09
R9 (Port 9)
IOC9
0A
RA
0B
RB
0C
RC
IOCC
0D
RD
IOCD
0E
RE
IOCE
0F
RF
IOCF
10
11
16x8
Common
Register
1E
1F
00
01
10
11
20
21
31x8
Bank
Register
31x8
Bank
Register
31x8
Bank
Register
31x8
Bank
Register
(Bank 0)
(Bank 1)
(Bank 2)
(Bank 3)
3E
3F
R3F
Fig. 4 Data memory configuration
Product Specification (V1.1) 06.30.2003
(This specification is subject to change without further notice)
•7
EM78P451
8-Bit Microcontroller with OTP ROM
4.1.8 RA (SPIRB: SPI Read Buffer)
Address
Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
0X0A
SPIRB/RA
SRB7
SRB6
SRB5
SRB4
SRB3
SRB2
SRB1
SRB7~SRB0 are the 8-bit data when complete transmission by SPI.
4.1.9 RB (SPIWB: SPI Write Buffer)
Address
Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
0x0B
SPIWB/RB
SWB7
SWB6
SWB5
SWB4
SWB3
SWB2
SWB1
SWB0
SWB7~SWB0 are the 8-bit data that are waiting for transmission by SPI.
4.1.10 RC (SPIS: SPI Status Segister)
Address
Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
0x0C
SPIS/RC
--
--
--
TM1IF
OD3
OD4
RBFIF
RBF
TM1IF (bit 4):
1 = In timer1 mode, receiving completed, and an interrupt occurs if
enabled.
0 = In timer1 mode, receiving not completed yet, and an interrupt does
not occur.
OD3 (bit 3): Open-Drain Control bit
1 = Open-drain enable for SDO,
0 = Open-drain disable for SDO.
OD4 (bit 2): Open-Drain Control bit
1 = Open-drain enable for SCK,
0 = Open-drain disable for SCK.
RBFIF (bit 1):Read Buffer Full Interrupt Flag
1 = Receiving completed, SPIRB is fully exchanged, and an interrupt
occurs if enabled.
0 = Receiving not completed yet; and SPIRB has not fully exchanged.
RBF (bit 0): Read Buffer Full flag
1 = Receiving completed; SPIRB is fully exchanged.
0 = Receiving not completed yet, and SPIRB has not fully exchanged.
8•
Product Specification (V1.1) 06.30.2003
(This specification is subject to change without further notice)
EM78P451
8-Bit Microcontroller with OTP ROM
4.1.11 RD (SPIC: SPI Control Register)
Address
Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
0x0D
SPIC/RD
CES
SPIE
SRO
SSE
-
Bit 2
Bit 1
Bit 0
SBRS2 SBRS1 SBRS0
CES (bit 7): Clock Edge Select bit
1 = Data shifts out on falling edge, and shifts in on rising edge. Data is on
hold during the high level.
0 = Data shifts out on rising edge, and shifts in on falling edge. Data is on
hold during the low level.
SPIE (bit 6): SPI Enable bit
1= Enable SPI mode
0= Disable SPI mode
SRO (bit 5): SPI Read Overflow bit
1 = A new data is received while the previous data is still being held in the
SPIB register. In this situation, the data in SPIS register will be
destroyed. To avoid setting this bit, users had better read SPIRB
register even if only the transmission is implemented.
0 = No overflow.
NOTE
This can only occur in slave mode.
SSE (bit 4): SPI Shift Enable bit
1 = Start to shift, and keep on 1 while the current byte is still being
transmitted.
0 = Reset as soon as the shifting is complete, and the next byte is ready to
shift.
NOTE
This bit will reset to 0 at every one-byte transmission by the hardware
SBRS (bit 2~bit 0): SPI Baud Rate Select bits
SPI baud rate table is illustrated in SPI section in later pages.
4.1.12 RE (TMR1: Timer1 register)
Address
0X0E
Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
TMR1/RE TMR17 TMR16 TMR15 TMR14 TMR13 TMR12 TMR11 TMR10
TMR17~TMR10 is bit set of timer1 register and it increases until the value matches
PWP and then, it resets to 0.
Product Specification (V1.1) 06.30.2003
(This specification is subject to change without further notice)
•9
EM78P451
8-Bit Microcontroller with OTP ROM
4.1.13 RF (PWP: Pulse width preset register)
Address
0x0F
Name
Bit 7
PWP/RF PWP7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
PWP6
PWP5
PWP4
PWP3
PWP2
PWP1
PWP0
PWP7~PWP0 is bit set of pulse width preset in advance for the desired width of baud
clock.
4.1.14 R20~R3E (General Purpose Register)
RA~R1F, and R20~R3E (including Banks 0~3) are general-purpose registers.
4.1.15 R3F (Interrupt Status Register)
Address
Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
0x3F
ISR/R3F
-
-
-
-
TM1IF
SPIIF
EXIF
TCIF
Bit 0 (TCIF) the flag of the TCC overflow interrupt. Set as TCC overflow; flag cleared
by software.
Bit 1 (EXIF) External interrupt flag. Set by falling edge on /INT pin, flag cleared by
software
Bit 2 (SPIIF) SPI interrupt flag. Set by data transmission complete, flag cleared by
software.
Bit 3 (TM1IF) Timer1 interrupt flag. Set by the comparator at Timer1 application, flag
cleared by software.
Bits 2~7
are not used and read as “0”.
"1" means interrupt request, "0" means non-interrupt.
R3F can be cleared by instruction, but cannot be set by instruction.
IOCF is the interrupt mask register.
Note that to read R3F will result to "logic AND" of R3F and IOCF.
4.2 Special Purpose Registers
4.2.1 A (Accumulator)
Internal data transfer, or instruction operand holding.
A non-addressable register.
4.2.2 CONT (Control Register)
7
6
5
4
3
2
1
0
/PHEN
/INT
-
-
PAB
PSR2
PSR1
PSR0
Bit 7 (/PHEN) I/O pin pull-high enable flag.
0: For P60~P67, P74~P75 and P90~P95, the pull-high function is
enabled.
1: The pull-high function is disabled.
10 •
Product Specification (V1.1) 06.30.2003
(This specification is subject to change without further notice)
EM78P451
8-Bit Microcontroller with OTP ROM
Bit 6 (INT)
An interrupt enable flag cannot be written by the CONTW instruction.
0: interrupt masked by the DISI instruction.
1: interrupt enabled by the ENI or RETI instruction.
Bit4, 5
Not used, and to be read as “0”.
Bit 3 (PAB) Prescaler assignment bit.
0: TCC
1: WDT
Bit 0 (PSR0) ~ Bit 2 (PSR2) TCC/WDT prescaler bits.
PSR2
PSR1
PSR0
TCC Rate
WDT Rate
0
0
0
1:2
1:1
0
0
1
1:4
1:2
0
1
0
1:8
1:4
0
1
1
1:16
1:8
1
0
0
1:32
1:16
1
0
1
1:64
1:32
1
1
0
1:128
1:64
1
1
1
1:256
1:128
Bits 0~3, and 7 of the CONT register are readable and writable.
4.2.3 IOC5 ~ IOC9 (I/O Port Control Register)
"1" put the relative I/O pin into high impedance, while "0" put the relative I/O pin as
output.
Both P74 and P76 should not be defined as output pins at the same time. This also
applies to both P75 and P77.
Only the lower 6 bits of the IOC9 register are used.
4.2.4 IOCC (T1CON: Timer1 Control Register)
Address
Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
0x0C
T1CON/IOCC
0
0
0
0
0
TM1E
Bit 1
Bit 0
TM1P1 TM1P0
TM1E (bit2): Timer1 Function Enable bit
1 = Enable timer1 function.
0 = Disable timer1 function as default.
TM1P (bit1~bit0): Timer1 Prescaler bit
Timer1 prescaler table for FOSC will be illustrated in the Section on
Timer1 in later pages.
Product Specification (V1.1) 06.30.2003
(This specification is subject to change without further notice)
• 11
EM78P451
8-Bit Microcontroller with OTP ROM
4.2.5 IOCD (Pull-high Control Register)
7
6
5
4
3
2
1
0
S7
-
-
-
/PU9
/PU8
/PU6
/PU5
The default values of /PU5, /PU6, /PU8, and /PU9 are one, which means the pull-high
function is disabled.
/PU6 and /PU9 are “AND” gating with /PHEN, that is, when each one is written as “0”
pull high is enabled.
S7 defines the driving ability of the P70-P72.
0: Normal output.
1: Enhance the driving ability of LED.
4.2.6 IOCE (WDT Control Register)
7
6
5
4
3
2
1
0
-
ODE
WDTE
SLPC
ROC
-
-
/WUE
Bit 0 (/WUE) Control bit used to enable the wake-up function of P60~P67, P74~P75,
and P90~P91.
0: Enable the wake-up function.
1: Disable the wake-up function.
The /WUE bit can be read and written.
Bit 3 (ROC) ROC is used for the R-option. Setting ROC to "1" will enable the status of
R-option pins (P80, P81) to be read by the controller. Clearing ROC will
disable the R-option function. Otherwise, the R-option function is
introduced. Users must connect the P81 pin or/and P80 pin to VSS by a
560KΩ external resistor (Rex). If Rex is connected/disconnected with
VDD, the status of P80 (P81) will be read as "0"/"1" (refer to Fig. 7(b)).
The ROC bit can be read and written.
Bit 4 (SLPC) This bit is set by hardware at the falling edge of wake-up signal and is
cleared in software. SLPC is used to control the oscillator operation. The
oscillator is disabled (oscillator is stopped, and the controller enters the
SLEEP2 mode) on the high-to-low transition and is enabled (the
controller is awakened from SLEEP2 mode) on low-to-high transition. In
order to ensure the stable output of the oscillator, once the oscillator is
enabled again, there is a delay for approximately 18 ms (oscillator
start-up timer (OST)) before the next program instruction is executed.
The OST is always activated by wake-up from sleep mode whether the
Code Option bit ENWDT is "0" or not. After waking up, the WDT is
enabled if Code Option ENWDT is "1". The block diagram of SLEEP2
mode and wake-up caused by input triggered is depicted in Fig. 5. The
SLPC bit can be read and written.
12 •
Product Specification (V1.1) 06.30.2003
(This specification is subject to change without further notice)
EM78P451
8-Bit Microcontroller with OTP ROM
Bit 5 (WDTE) Control bit used to enable Watchdog timer.
The WDTE bit can be used only if ENWDT, the CODE Option bit, is "1".
If the ENWDT bit is "1", then WDT can be disabled/enabled by the
WDTE bit.
0: Disable WDT.
1: Enable WDT.
The WDTE bit is not used if ENWDT, the CODE Option bit ENWDT, is
"0". That is, if the ENWDT bit is "0", WDT is always disabled no matter
what the WDTE bit is.
The WDTE bit can be read and written.
Bit 6 (ODE)
Open-drain control bit.
0: Both P76 and P77 are normally I/O pins.
1: Both P76 and P77 pins have the open-drain function inside.
The ODE bit can be read and written.
Bits 1~2, and 7 Not used.
4.2.7 IOCF (Interrupt Mask Register)
7
6
5
4
3
2
1
0
-
-
-
-
TM1IE
SPIIE
EXIE
TCIE
Bit 0 (TCIE) TCIF interrupt enable bit.
0: disable TCIF interrupt
1: enable TCIF interrupt
Bit 1 (EXIE) EXIF interrupt enable bit.
0: disable EXIF interrupt
1: enable EXIF interrupt
Bit 2 (SPIIE) SPI interrupt enable bit.
0: disable SPI interrupt
1: enable SPI interrupt
Bit 3 (TM1IE) TM1IE interrupt enable bit.
0: disable TM1IE interrupt
1: enable TM1IE interrupt
Bits 4~7
Not used.
Individual interrupt is enabled by setting its associated control bit in IOCF to "1".
The IOCF Register could be read and written.
Product Specification (V1.1) 06.30.2003
(This specification is subject to change without further notice)
• 13
EM78P451
8-Bit Microcontroller with OTP ROM
/WUE
Oscillator
Enable
Disable
/WUE
Reset
Q
Q
Clear
P D
R
CLK
C
L
VCC
Set
8
/WUE
from S/W
P60~P67
VCC
/WUE
/PHEN
4
P74~P75, P90~P91
Fig. 5 Block Diagram of Sleep Mode and Wake-up Circuits on I/O Ports
4.3 TCC/WDT Presacler
An 8-bit counter is available as prescaler for the TCC or WDT. The prescaler is
available for either the TCC or WDT only at any given time, and the PAB bit of CONT
register is used to determine the prescaler assignment. The PSR0~PSR2 bits
determine the prescale ratio. The prescaler is cleared each time the instruction is
written to TCC under TCC mode. The WDT and prescaler, when assigned to WDT
mode, are cleared by the WDTC or SLEP instructions. Fig. 6 depicts the circuit
diagram of TCC/WDT.
R1(TCC) is an 8-bit timer/counter. TCC will increase by one at every instruction cycle
(without prescaler).
The watchdog timer is a free running on-chip RC oscillator. The WDT will keep running
even when the oscillator driver has been turned off (i.e. in sleep mode). During normal
14 •
Product Specification (V1.1) 06.30.2003
(This specification is subject to change without further notice)
EM78P451
8-Bit Microcontroller with OTP ROM
operation or sleep mode, a WDT time-out (if enabled) will cause the device to reset.
The WDT can be enabled or disabled any time during the normal mode by software
programming (if Code Option bit ENWDT is "1"). Refer to WDTE bit of IOCE register.
Without presacler, the WDT time-out period is approximately 18 ms1.
4.4 I/O Ports
The I/O registers, from Port 5 to Port 9, are bi-directional tri-state I/O ports. P60~P67,
P74~P75, and P90~P91 provide internal pull-high. P60~P67, P74~P75, and P90~P95
provide programmable wake-up function through software. P76~P77 can have
open-drain output by software control. P80~P81 are the R-option pins which are
enabled by software. When the R-option function is used, it is recommended that P80
and P81 are used as output pins. During R-option enabled state, P80 and P81 must be
programmed as input pins. If an external resistor is connected to P80 (P81) for the
R-option function, the current consumption should be taken as an important factor in
the applications for low power consideration.
The I/O ports can be defined as "input" or "output" pins by the I/O control registers
(IOC5~IOC9) under program control. The I/O registers and I/O control registers are
both readable and writable. The I/O interface circuit is shown in Fig. 7. Note that the
reading path source of input and output pins is different when reading the I/O port.
Data Bus
CLK(=Fosc/2)
1
M
U
X
SYNC
TCC(R1)
2 cycles
0
TCC overflow interrupt
PAB
0
W DT
1
M
U
X
8- bit Counter
PSR0~PSR2
8 - to - 1 MUX
0
W DTE
1
MUX
PAB
(in IOCE)
W DT tim eout
Fig. 6 Block Diagram of TCC WDT
1
NOTE: Vdd = 5V, set up time period = 16.2ms ± 5%
Vdd = 3V, set up time period = 18.0ms ± 5%
Product Specification (V1.1) 06.30.2003
(This specification is subject to change without further notice)
• 15
EM78P451
8-Bit Microcontroller with OTP ROM
PCRD
Q
PORT
0
1
P
R
D
CLK
Q
C
L
Q
P
R
Q
C CLK
L
PCW R
IOD
D
PDW R
M
U
X
PDRD
Fig. 7 (a) The Circuit of I/O Port and I/O Control Register
PCRD
VCC
ROC
P D
R
CLK
Q C
L
Q
Weakly
Pull-up
P
R D
C CLK
Q L
PCWR
IOD
Q
PORT
0
Rex*
1
M
U
X
PDWR
PDRD
*The Rex is 560K ohm external resistor
Fig.7(b) The Circuit of I/O Port with R-option (P80, P81)
16 •
Product Specification (V1.1) 06.30.2003
(This specification is subject to change without further notice)
EM78P451
8-Bit Microcontroller with OTP ROM
4.5 SERIAL PERIPHERAL INTERFACE MODE
4.5.1 Overview & Features
4.5.1.1 Overview
Figures 8, 9, and 10 show how EM78P451 communicates with other devices through
SPI module. If EM78P451 is a master controller, it sends clock through the SCK pin. A
couple of 8-bit data are transmitted and received at the same time. However, if
EM78P451is defined as a slave, its SCK pin could be programmed as an input pin.
Data will continue to be shifted based on both the clock rate and the selected edge.
4.5.1.2 Features
Operation in either Master mode or Slave mode,
Three-wire or four-wire synchronous communication; that is, full duplex
Programmable baud rates of communication,
Programming clock polarity, (RD bit7)
Interrupt flag available for the read buffer full,
Up to 8 MHz ( maximum ) bit frequency,
SDO
SPIR Reg
SPIW
SPIW Reg
Reg
/SS
SPIS Reg
SDI
SPI Module
Bit 7
Master Device
SCK
Slave Device
Fig. 8 SPI Master/Slave Communication
Product Specification (V1.1) 06.30.2003
(This specification is subject to change without further notice)
• 17
EM78P451
8-Bit Microcontroller with OTP ROM
SDI
SDO
SCK
/SS
Vdd
Master
P50
P51
P52
P53
SDO
SDI
SCK
/SS
SDO
SDI
SCK
/SS
SDO
SDI
SCK
/SS
SDO
SDI
SCK
/SS
Slave Device 1
Slave Device 2
Slave Device 3
Slave Device 4
Fig. 9 The SPI Configuration of Single-Master and Multi-Slave
SDI
SDO
SCK
/SS
SDI
SDO
SCK
/SS
Master1
or
P50
Slave1 P51
Master2
or
P50
P51 Slave6
P52
P53
Slave 4 for Master1/2
SDO
SDI
SCK
/SS
Slave 3 for Master 1/2
SDO
SDI
SCK
/SS
SDO
SDI
SCK
/SS
SDO
SDI
SCK
/SS
Slave 2 for m aster 1
P52
P53
Slave 5 for Master 2
Fig. 10 The SPI Configuration of Single-Master and Multi-Slave
18 •
Product Specification (V1.1) 06.30.2003
(This specification is subject to change without further notice)
EM78P451
8-Bit Microcontroller with OTP ROM
4.5.2 SPI Function Description
Read
RBF
RBFI
Write
SPIR
SE
reg
SPIW reg
Set to 1
Buffer Full Detector
SPIS
P92/SDI
shift right
reg
bit 0
bit 7
SPIC reg
P93/SDO
Edge
Select
SBR0 ~SBR2
P95/ /SS
SBR2~SBR0
8
/ SS
Prescaler
4, 8, 16, 32, 64
Tsco
Noise
Filter
Clock Select
2
Edge
Select
P94/SCK
TMR1/2
SPIC bit6
Fig. 11 SPI Block Diagram
SPI
SDI
Shift Clock
SPI Read Register
(0X0A)
7~0
SPIWB
/SS
SPI Write Register
(0X0B)
8-1 MUX
SPI Mode Select
Register
2 1 0
SPIC
SDO
SPI Shift Buffer
FOSC
1 0
7 6 4 1 0
T1CON
SPIC
SPIS
2
4
INTC
SPIC
7~0
SPIRB
DATA BUS
Fig. 12 The Function Block Diagram of SPI Transmission
The following describes the function of each block and explains how to carry out the
SPI communication with the signals depicted in Fig.11 and Fig.12:
Product Specification (V1.1) 06.30.2003
(This specification is subject to change without further notice)
• 19
EM78P451
8-Bit Microcontroller with OTP ROM
P92/SDI:
Serial Data In.
P93/SDO:
Serial Data Out.
P94/SCK:
Serial Clock.
P95//SS:
/Slave Select (Option). This pin (/SS) may be required during a slave
mode.
RBF:
Set by Buffer Full Detector, and reset in software.
RBIF:
Set by Buffer Full Detector, and reset in software.
Buffer Full Detector: Sets to 1 when an 8-bit shifting is completed.
SSE:
Loads the data in SPIS register, and begin to shift
SPIS reg.:
Shifting byte in and out. The MSB is shifted first. Both the SPIS
register and the SPIW register are loaded at the same time. Once
data are written, SPIS starts transmission / reception. The received
data will be moved to the SPIR register as the shifting of the 8-bit data
is completed. The RBF (Read Buffer Full) flag and the RBFI(Read
Buffer Full Interrupt) flag are then set.
SPIR reg.:
Read buffer. The buffer will be updated as the 8-bit shifting is
completed. The data must be read before the next reception is
completed. The RBF flag is cleared as the SPIR register reads.
SPIW reg.:
Write buffer. The buffer will deny any attempt to write until the 8-bit
shifting is completed.
The SSE bit will be kept in 1 if the communication is still undergoing.
This flag must be cleared as the shifting is completed. Users can
determine if the next write attempt is available.
SBRS2~SBRS0: Programming the clock frequency/rates and sources.
Clock Select:
Selecting either the internal or external clock as the shifting clock.
Edge Select:
Selecting the appropriate clock edges by programming the CES bit
4.5.3 SPI Signal & Pin Description
The detailed functions of the four pins, SDI, SDO, SCK, and /SS, which are shown in
Fig. 9, are as follows:
SDI/P92 (Pin 7):
Serial Data In,
Receive serially, the Most Significant Bit (MSB) first, Least Significant Bit (LSB)
last,
Defined as high-impedance, if not selected,
20 •
Product Specification (V1.1) 06.30.2003
(This specification is subject to change without further notice)
EM78P451
8-Bit Microcontroller with OTP ROM
Program the same clock rate and clock edge to latch on both the master and slave
devices,
The received byte will update the transmitted byte,
Both the RBF and RBFIF bits (located in Register 0x0C) will be set as the SPI
operation is completed.
Timing is shown in Fig.13 and14.
SDO/P93 (Pin 8):
Serial Data Out,
Transmit serially; the Most Significant Bit (MSB) first, Least Significant Bit (LSB)
last,
Program the same clock rate and clock edge to latch on both the master and slave
devices,
The received byte will update the transmitted byte,
The CES (located in Register 0x0D) bit will be reset, as the SPI operation is
completed.
Timing is shown in Fig.13 and 14.
SCK/P94 (Pin 9):
Serial Clock
Generated by a master device
Synchronize the data communication on both the SDI and SDO pins
The CES (located in Register 0x0D) is used to select the edge to communicate.
The SBR0~SBR2 (located in Register 0x0D) is used to determine the baud rate of
communication
The CES, SBR0, SBR1, and SBR2 bits have no effect in the slave mode
Timing is show in Fig.13 and 14
/SS/P95 (Pin 10):
Slave Select; negative logic,
Generated by a master device to signify the slave(s) to receive data,
Goes low before the first cycle of SCK appears, and remains low until the last
(eighth) cycle is completed,
Ignores the data on the SDI and SDO pins while /SS is high, because the SDO is
no longer driven.
Timing is shown in Fig.13 and Fig. 14.
Product Specification (V1.1) 06.30.2003
(This specification is subject to change without further notice)
• 21
EM78P451
8-Bit Microcontroller with OTP ROM
4.5.4 Programmed the Related Registers
As the SPI mode is defined, the related registers of this operation are shown in Table 2
and Table 3.
Table 2 Related Control Registers of the SPI Mode
Address
Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
0x0D
*SPIC/RD
CES
SPIE
SRO
SSE
--
SBR2
SBR1
SBR0
0x0F
INTC/IOCF
--
--
--
--
TM1IE
SPIIE
EXIE
TCIE
SPIC:
SPI Control Register.
CES (bit 7): Clock Edge Select bit
1 = Data shifts out on falling edge, and shifts in on rising edge. Data is on
hold during the high level.
0 = Data shifts out on rising edge, and shifts in on falling edge. Data is on
hold during the low level.
SPIE (bit 6):SPI Enable bit
1 = Enable SPI mode
0 = Disable SPI mode
SRO (bit 5): SPI Read Overflow bit
1 = A new data is received while the previous data is still being on hold in
the SPIB register. Under this condition, the data in SPIS register will be
destroyed. To avoid setting this bit, users should read the SPIRB register
even if the transmission is implemented only.
0 = No overflow.
NOTE
This can only occur under slave mode.
SSE (bit 4): SPI Shift Enable bit
1 = Start to shift, and stays on 1 while the current byte continues to
transmit.
0 = Reset as soon as the shifting is completed and the next byte is ready
to shift.
NOTE
This bit can be reset by hardware only.
22 •
Product Specification (V1.1) 06.30.2003
(This specification is subject to change without further notice)
EM78P451
8-Bit Microcontroller with OTP ROM
SBRS (bit 2~0): SPI Baud Rate Select Bits
SBRS2 (Bit 2) SBRS1 (Bit 1) SBRS0 (Bit 0)
0
0
0
0
1
1
1
1
0
0
1
1
0
0
1
1
0
1
0
1
0
1
0
1
Mode
Baud Rate
Master
Master
Master
Master
Master
Slave
Slave
Master
Fsco/2
Fsco/4
Fsco/8
Fsco/16
Fsco/32
/SS enable
/SS disable
TMR1/2
NOTE
In master mode, /SS is disable.
INTC:
Interrupt control register
Bit 3 (TM1IE) TM1IE interrupt enable bit.
0: disable TM1IE interrupt
1: enable TM1IE interrupt
Bit 2 (SPIIE) SPI interrupt enable bit.
0: disable SPI interrupt
1: enable SPI interrupt
Bit 1 (EXIE) EXIF interrupt enable bit.
0: disable EXIF interrupt
1: enable EXIF interrupt
Bit 0 (TCIE) TCIF interrupt enable bit.
0: disable TCIF interrupt
1: enable TCIF interrupt
Table 3 Related Status/Data Registers of the SPI Mode
Address
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
0X0A
SPIRB/RA SRB7
SRB6
SRB5
SRB4
SRB3
SRB2
SRB1
SRB0
0x0B
SPIWB/RB SWB7
SWB6
SWB5
SWB4
SWB3
SWB2
SWB1
SWB0
0
0
TM1IF
OD3
OD4
RBFIF
RBF
0x0C
Name
SPIS/RC
0
SPIRB:
SPI Read Buffer. Once the serial data is received completely, it will load
to SPIRB from SPISR. The RBF bit and the RBFIF bit in the SPIS
register will be set also.
SPIWB:
SPI Write Buffer. As a transmitted data is loaded, the SPIS register
stands by and start to shift the data when sensing SCK edge with SSE
set to “1”.
Product Specification (V1.1) 06.30.2003
(This specification is subject to change without further notice)
• 23
EM78P451
8-Bit Microcontroller with OTP ROM
SPIS:
SPI Status register
TM1IF (bit 4): Timer1 interrupt flag.
OD3 (bit 3):
Open-Drain Control bit (P93)
1 = Open-drain enable for SDO,
0 = Open-drain disable for SDO.
OD4 (bit 2):
Open Drain-Control bit (P94)
1 = Open-drain enable for SCK,
0 = Open-drain disable for SCK.
RBFIF (bit 1): Read Buffer Full Interrupt flag
1 = Receive is completed, SPIB is full, and an interrupt occurs if
enabled.
0 = Receive is ongoing, SPIB is empty.
RBF (bit 0):
Read Buffer Full flag
1 = Receive is completed, SPIB is full.
0 = Receive is ongoingt, SPIB is empty.
4.5.5 SPI Mode Timing
The edge of SCK is selected by programming bit CES. The waveform shown in Fig.13
is applicable regardless of whether the EM78P451 is under master or slave mode with
/SS disabled. However, The waveform in Fig. 14 can only be implemented in slave
mode with /SS enabled.
Fig. 13 SPI Mode with /SS Disable
24 •
Product Specification (V1.1) 06.30.2003
(This specification is subject to change without further notice)
EM78P451
8-Bit Microcontroller with OTP ROM
Fig. 14 SPI Mode with /SS Enable
4.5.6 Software Application of SPI
Example for SPI:
For Master
ORG 0X0
SETTING:
CLRA
IOW 0X05
;Set Port5 output
IOW 0X06
;Set Port6 output
MOV 0X05,A
MOV A,@0B11001111
;Set prescaler for WDT
CONTW
MOV A,@0B00010001
;Disable wakeup function
IOW 0X0E
MOV A,@0B00000000
;Disable interrupt
IOW 0X0F
MOV A,@0x07
;SDI input and SDO, SCK output
IOW 0x09
MOV A,@0B10000000
;Clear RBF and RBFIF flag
MOV 0x0C,A
MOV A,@0B11100000
;Select clock edge and enable SPI
MOV 0X0D,A
START:
Product Specification (V1.1) 06.30.2003
(This specification is subject to change without further notice)
• 25
EM78P451
8-Bit Microcontroller with OTP ROM
WDTC
BC 0X0C,1
;Clear RBFIF flag
MOV A,@0XFF
MOV 0X05,A
;Show a signal at Port5
MOV 0X0A,A
;Move FF at read buffer
MOV A,@0XAA
;Move AA at write buffer
MOV 0X0B,A
BS 0X0D,4
;Start to shift SPI data
NOP
JBC 0X0D,4
;Polling loop for checking SPI transmission
completed
JMP $-2
BC 0X03,2
CALL DELAY
;To catch the data from slaver
MOV A,0X0A
XOR A,@0X5A
;Compare the data from slaver
JBS 0X03,2
JMP START
FLAG:
MOV A,@0X55
;Show the signal when receiving correct data
from slaver
MOV 0X05,A
CALL DELAY
JMP START
DELAY:
;(user’s program)
EOP
ORG 0XFFF
JMP SETTING
26 •
Product Specification (V1.1) 06.30.2003
(This specification is subject to change without further notice)
EM78P451
8-Bit Microcontroller with OTP ROM
For Slaver
ORG 0X0
INITI:
JMP INIT
ORG 0X2
INTERRUPT:
;Interrupt address
MOV A,@0X55
MOV 0X06,A
;Show a signal at Port 6 when entering
interrupt
MOV A,@0B11100110
;Enable SPI, /SS disabled
MOV 0X0D,A
BS 0X0D,4
;Keep SSE at 1 to wait for SCK signal in order
to shift data
MOV A,@0X00
;Move 00 to write buffer in order to keep
master’s read buffer as 00
MOV 0X0B,A
BS 0X0D,4
;Keep SSE at 1 to wait for SCK signal in order
to shift data
NOP
JBC 0X0D,4
;Polling loop for checking SPI transmission
completed
JMP $-2
BS 0X0D,4
BC
;Keep SSE at 1 to wait for SCK signal in order
to shift data
0X03,2
MOV A,0X0A
MOV 0X06,A
;Read master’s data from read buffer
XOR A,@0XAA
;Check pass signal from read buffer
JBS 0X03,2
JMP $-6
JMP SPI
ORG 0X30
INIT:
CLRA
IOW 0X05
IOW 0X06
MOV 0x05,A
Product Specification (V1.1) 06.30.2003
(This specification is subject to change without further notice)
• 27
EM78P451
8-Bit Microcontroller with OTP ROM
MOV 0X06,A
MOV A,@0XFF
IOW 0X08
MOV A,@0B11001111
;Set prescaler for WDT
CONTW
MOV A,@0B00010001
;Disable wakeup function
IOW 0X0E
MOV A,@0B00000010
;Enable external interrupt
IOW 0XF
ENI
MOV A,@0B00110111
IOW 0x09
BC
0X3F,1
;Clear RBFIF flag
NOP
JBS 0X3F,1
;Polling loop for checking interrupt
occurence
JMP $-2
JMP INTERRUPT
SPI:
BS 0X0D,4
;Keep SSE enabled as long as possible
WDTC
MOV A,@0X0F
;Show a signal when entering SPI loop
MOV 0X06,A
JBC 0X08,1
;Choose P81 as a signal button
JMP SPI
MOV A,@0X5A
;Move 5A into write buffer when P81 button is
pushed
MOV 0X0B,A
NOP
JBC 0X0D,4
;Polling loop for checking SPI transmission
completed
JMP $-2
BS 0XD,4
NOP
NOP
MOV A,@0XF0
;Display at Port6 when P81 button is pushed
MOV 0X06,A
28 •
Product Specification (V1.1) 06.30.2003
(This specification is subject to change without further notice)
EM78P451
8-Bit Microcontroller with OTP ROM
MOV A,@0X00
;Send a signal to master to prevent infinite
loop
MOV 0X0B,A
NOP
JBC 0X0D,4
JMP $-2
BS 0X0D,4
BS 0x0C,7
BC 0x0C,1
NOP
JMP SPI
DELAY:
;(user’s program)
EOP
ORG 0XFFF
JMP INITI
4.6 Timer 1
4.6.1 Overview
Timer1(TMR1) is an eight-bit clock counter with a programmable prescaler. It is
designed for the SPI module as a baud rate clock generator. TMR1 can be read and
written and cleared on any reset conditions. If employed, it can be turned down for
power saving by setting TMR1EN bit [T1CON<2>] to 0.
Product Specification (V1.1) 06.30.2003
(This specification is subject to change without further notice)
• 29
EM78P451
8-Bit Microcontroller with OTP ROM
4.6.2 Function Description
Fig. 15 shows TIMER1 block diagram. Each signal and block is described as follows:
Fig. 15 TIMER1 Block Diagram
OSC/4:
Input clock.
Prescaler:
Option of 1:1, 1:4, 1:8, and 1:16 defined by T1P1 and T1P02 (T1CON<1,
0>). It is cleared when a value is written to TMR1 or T1CON, and during
any kind of reset as well.
PWP:
Pulse width preset register. The desired width of baud clock is written in
advance.
TMR1:
Timer 1 register. TMR1 increases until it matches with PWP, and then
resets to 0. If it is chosen optionally in the SPI mode, its output is fed as
a shifting clock.
Comparator: To change the output status while a match occurs. The TMR1IF flag will
be set at the same time.
4.6.3 Programmed the Related Registers
The related registers of the defining TMR1 operation are shown in Table 4 and Table 5
Table 4 Related Control Registers of the TMR1
30 •
Address
Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
0x0C
SPIS/RC
0
0
0
TM1IF
OD3
OD4
RBFIF
RBF
0x0F
INTC/IOCF
0
0
0
0
TM1IE
SPIIE
EXIE
TCIE
Product Specification (V1.1) 06.30.2003
(This specification is subject to change without further notice)
EM78P451
8-Bit Microcontroller with OTP ROM
Table 5 Related Status/Data Registers ofTMR1
Address
Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
0X0E
TMR1/RE TMR17 TMR16 TMR15 TMR14 TMR13 TMR12 TMR11 TMR10
0x0F
PWP/RF
PWP7
PWP6
PWP5
PWP4
PWP3
PWP2
PWP1
0x0C
T1CON/IOCC
0
0
0
0
0
TM1E
TM1P1 TM1P0
TMR1:
PWP0
Timer1 Register
TMR17~TMR10 is bit set of Timer1 register and it increases until the
value matches PWP and then it reset to 0.
PWP:
Pulse Width Preset Register
PWP7~PWP0 is bit set of pulse width preset for the desired width of baud
clock in advance.
T1CON:
Timer1 Control Register
TM1E (bit2): Timer1 enable bit
TM1P1 and TM1P0 (bit1~0): Timer1 prescaler for FSCO
TM1P1
TM1P0
Prescaler Rate
0
0
1
1
0
1
0
1
1:1
1:4
1:8
1:16
4.7 RESET and Wake-up
A RESET is initiated by
(1) Power on reset, or
(2) WDT timeout. (if enabled)
VDD
D
Oscillator
Q
CLK
CLK
CLR
Pow eron Reset
Voltage
Detector
W DTE
W DT tim eout
W DT
Setup
Tim e
Reset
Fig. 16 Block Diagram of Reset
Product Specification (V1.1) 06.30.2003
(This specification is subject to change without further notice)
• 31
EM78P451
8-Bit Microcontroller with OTP ROM
EM78P451 POR voltage range is 1.2V~1.8V. Under customer application, when
power is OFF, Vdd must drop to below 1.2V and remains OFF for 10us before power
can be switched ON again. This way, the EM78P451 will reset and work normally. The
extra external reset circuit will work well if Vdd can rise at very fast speed (50 ms or
less). However, under most cases where critical applications are involved, extra
devices are required to assist in solving the power-up problem.
The device is kept in a RESET condition for a period of approx. 18ms2 (one oscillator
start-up timer period) after the reset is detected and Fig.16 is the block diagram of
reset. Once the RESET occurs, the following functions are performed.
The oscillator is running, or will be started.
The Program Counter (R2) is set to all "1".
When power is switched on, bits 5~6 of R3 and the upper 2 bits of R4 are cleared.
All I/O port pins are configured as input mode (high-impedance state).
The Watchdog timer and prescaler are cleared.
The Watchdog timer is enabled if Code Option bit ENWDT is "1".
The CONT register is set to all "1" except bit 6 (INT flag).
Bits 3,6 of IOCE register are cleared, bits 0,4~5 of IOCE register are set to "1".
Bits 0 of R3F and bits 0 of IOCF registers are cleared.
The sleep mode (power down) is achieved by executing the SLEP instruction (named
as SLEEP1 MODE). While entering sleep mode, the WDT (if enabled) is cleared but
keeps on running. The controller is awakened by WDT timeout (if enabled), and it will
cause the controller to reset. The T and P flags of R3 are used to determine the source
of the reset (wake-up).
In addition to the basic SLEEP1 MODE, EM78P451 has another sleep mode (caused
by clearing "SLPC" bit of IOCE register, designated as SLEEP2 MODE). In the
SLEEP2 MODE, the controller can be awakened by(a) Any one of the wake-up pins is set to “0.” (refer to Fig.17). Upon waking, the
controller will continue to execute the program in-line. In this case, before entering
SLEEP2 MODE, the wake-up function of the trigger sources (P60~P67, P74~P75,
and P90~P91)should be selected (e.g. input pin) and enabled (e.g. pull-high,
wake-up control). One caution should be noted is that after waking up, the WDT is
enabled if Code Option bit ENWDT is "1". The WDT operation (to be enabled or
disabled) should be appropriately controlled by software after waking up.
(b) WDT time-out (if enabled). On wake-up, will cause the controller reset.
2
32 •
NOTE: Vdd = 5V, set up time period = 16.2ms ± 5%
Vdd = 3V, set up time period = 18.0ms ± 5%
Product Specification (V1.1) 06.30.2003
(This specification is subject to change without further notice)
EM78P451
8-Bit Microcontroller with OTP ROM
Table 6 The Summary of the Initialized Values for Registers
Address
Name
N/A
IOC5
N/A
N/A
N/A
N/A
N/A
0x00
0x01
0x02
0x03
IOC6
IOC7
IOC8
IOC9
CONT
R0(IAR)
R1(TCC)
R2(PC)
R3(SR)
Reset Type
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Bit Name
Power-On
/RESET and WDT
Wake-Up from Pin
Change
C57
1
1
C56
1
1
C55
1
1
C54
1
1
C53
1
1
C52
1
1
C51
1
1
C50
1
1
P
P
P
P
P
P
P
P
Bit Name
Power-On
/RESET and WDT
Wake-Up from Pin
Change
C67
1
1
C66
1
1
C65
1
1
C64
1
1
C63
1
1
C62
1
1
C61
1
1
C60
1
1
P
P
P
P
P
P
P
P
Bit Name
Power-On
/RESET and WDT
Wake-Up from Pin
Change
C77
1
1
C76
1
1
C75
1
1
C74
1
1
C73
1
1
C72
1
1
C71
1
1
C70
1
1
P
P
P
P
P
P
P
P
Bit Name
Power-On
/RESET and WDT
Wake-Up from Pin
Change
C87
1
1
C86
1
1
C85
1
1
C84
1
1
C83
1
1
C82
1
1
C81
1
1
C80
1
1
P
P
P
P
P
P
P
P
Bit Name
Power-On
/RESET and WDT
Wake-Up from Pin
Change
C97
1
1
C96
1
1
C95
1
1
C94
1
1
C93
1
1
C92
1
1
C91
1
1
C90
1
1
P
P
P
P
P
P
P
P
1
1
1
1
PAB
1
1
Bit Name
Power-On
/RESET and WDT
Wake-Up from Pin
Change
/PHEN /INT
1
0
1
P
PSR2 PSR1 PSR0
1
1
1
1
1
1
P
P
P
P
P
P
P
P
Bit Name
Power-On
/RESET and WDT
Wake-Up from Pin
Change
U
P
U
P
U
P
U
P
U
P
U
P
U
P
U
P
P
P
P
P
P
P
P
P
Bit Name
Power-On
/RESET and WDT
Wake-Up from Pin
Change
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
P
P
P
P
P
P
P
P
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
**P
**P
**P
**P
**P
**P
**P
**P
GP
0
0
PS1
0
0
PS0
0
0
T
t
t
P
t
t
Z
U
P
DC
U
P
C
U
P
Bit Name
Power-On
/RESET and WDT
Wake-Up from Pin
Change
Bit Name
Power-On
/RESET and WDT
Product Specification (V1.1) 06.30.2003
(This specification is subject to change without further notice)
• 33
EM78P451
8-Bit Microcontroller with OTP ROM
Address
Name
Reset Type
Wake-Up from Pin
Change
0x04
0x05
0x06
0x07
0x08
0x09
0x0A
0x0B
R4(RSR)
R5(P5)
R6(P6)
R7(P7)
R8(P8)
R9(P9)
RA(SPIRB)
RB(SPIWB)
Bit Name
Power-On
/RESET and WDT
Wake-Up from Pin
Change
RC(SPIS)
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
P
P
P
t
t
P
P
P
U
P
U
P
U
P
U
P
U
P
U
P
RSR.1 RSR.0
0
0
0
0
P
P
P
P
P
P
P
Bit Name
Power-On
/RESET and WDT
Wake-Up from Pin
Change
P57
U
P
P56
U
P
P55
U
P
P54
U
P
P53
U
P
P52
U
P
P51
U
P
P50
U
P
P
P
P
P
P
P
P
P
Bit Name
Power-On
/RESET and WDT
Wake-Up from Pin
Change
P67
U
P
P66
U
P
P65
U
P
P64
U
P
P63
U
P
P62
U
P
P61
U
P
P60
U
P
P
P
P
P
P
P
P
P
Bit Name
Power-On
/RESET and WDT
Wake-Up from Pin
Change
P77
U
P
P76
U
P
P75
U
P
P74
U
P
P73
U
P
P72
U
P
P71
U
P
P70
U
P
P
P
P
P
P
P
P
P
Bit Name
Power-On
/RESET and WDT
Wake-Up from Pin
Change
P87
U
P
P86
U
P
P85
U
P
P84
U
P
P83
U
P
P82
U
P
P81
U
P
P80
U
P
P
P
P
P
P
P
P
P
Bit Name
Power-On
/RESET and WDT
Wake-Up from Pin
Change
P97
U
P
P96
U
P
P95
U
P
P94
U
P
P93
U
P
P92
U
P
P91
U
P
P90
U
P
P
P
P
P
P
P
P
P
Bit Name
Power-On
/RESET and WDT
Wake-Up from Pin
Change
SRB7 SRB6 SRB5 SRB4 SRB3 SRB2 SRB1 SRB0
U
U
U
U
U
U
U
U
P
P
P
P
P
P
P
P
Bit Name
Power-On
/RESET and WDT
Wake-Up from Pin
Change
SWB7 SWB6 SWB5 SWB4 SWB3 SWB2 SWB1 SWB0
U
U
U
U
U
U
U
U
P
P
P
P
P
P
P
P
Power-On
/RESET and WDT
Wake-Up from Pin
Change
Bit Name
34 •
Bit 6
P
Bit Name
0x0C
Bit 7
P
P
P
P
P
P
ENSD
OBDC IBDC
O
0
0
0
0
0
0
P
P
CES
SPIE
P
P
P
P
P
TIIF
OD3
0
0
0
0
0
0
0
0
0
0
P
P
P
P
P
-
P
P
P
SRO SPISE
P
P
P
OD4 RBFIF RBF
SBRS SBRS SBRS
Product Specification (V1.1) 06.30.2003
(This specification is subject to change without further notice)
EM78P451
8-Bit Microcontroller with OTP ROM
Address
Name
0x0D
RD(SPIC)
Reset Type
0x0F
0x3F
0x0C
0x0D
0x0E
0x0F
0x10~0x3
E
RE(TMR1)
RF(PWP)
R3F(ISR)
IOCC
IOCD
IOCE
IOCF
GPR
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
0
0
0
0
0
0
0
0
0
0
2
0
0
1
0
0
0
0
0
P
P
P
P
P
P
P
P
Power-On
/RESET and WDT
Wake-Up from Pin
Change
Bit Name
0x0E
Bit 7
Power-On
/RESET and WDT
Wake-Up from Pin
Change
Bit Name
Power-On
/RESET and WDT
Wake-Up from Pin
Change
TMR1 TMR1 TMR1 TMR1 TMR1 TMR1 TMR1 TMR1
7
6
5
4
3
2
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
P
P
P
P
P
P
P
P
PWP7 PWP6 PWP5 PWP4 PWP3 PWP2 PWP1 PWP0
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
P
P
P
P
P
P
P
P
Bit Name
Power-On
/RESET and WDT
Wake-Up from Pin
Change
U
U
U
U
U
U
U
U
T1IF
0
0
SPIIF
0
0
EXIF
0
0
TCIF
0
0
U
U
U
U
P
P
P
P
Bit Name
Power-On
/RESET and WDT
Wake-Up from Pin
Change
0
0
0
0
0
0
0
0
0
0
T1E
0
0
P
P
P
P
P
P
P
P
Bit Name
Power-On
/RESET and WDT
Wake-Up from Pin
Change
S7
1
1
1
1
1
1
1
1
/PU9
1
1
/PU8
1
1
/PU6
1
1
/PU5
1
1
P
P
P
P
P
P
P
P
Bit Name
Power-On
/RESET and WDT
Wake-Up from Pin
Change
U
U
ODE
0
0
U
U
U
U
/WUE
1
1
U
P
1
1
P
U
U
P
Bit Name
Power-On
/RESET and WDT
Wake-Up from Pin
Change
U
U
U
U
U
U
U
U
T1IE
0
0
U
U
U
U
P
P
P
P
Bit Name
-
-
-
-
-
-
-
-
Power-On
U
U
U
U
U
U
U
U
/RESET and WDT
Wake-Up from Pin
Change
P
P
P
P
P
P
P
P
P
P
P
P
P
P
P
P
WTE SLPC ROC
1
1
0
1
1
0
T1P1 T1P0
0
0
0
0
SPIIE EXIE
0
0
0
0
TCIE
0
0
** To execute the next instruction after the ”SLPC” bit status of IOCE register being on
high-to-low transition.
Product Specification (V1.1) 06.30.2003
(This specification is subject to change without further notice)
• 35
EM78P451
8-Bit Microcontroller with OTP ROM
X: Not used. U: Unknown or don’t care. P: Previous value before reset.
t : Check Table 7
4.7.1 The Status of RST, T, and P of STATUS Register
A RESET condition is initiated by the following events:
1. A power-on condition,
2. Watchdog timer time-out.
The values of T and P, listed in Table 7 are used to check how the processor wakes up.
Table 8 shows the events that may affect the status of T and P.
Table 7 The Values of RST, T and P After RESET
Reset Type
T
P
Power on
WDT during Operating mode
1
0
1
P
WDT wake-up during SLEEP1 mode
0
0
WDT wake-up during SLEEP2 mode
0
P
Wake-Up on pin change during SLEEP2 mode
P
P
* P: Previous value before reset
Table 8 The Status of RST, T and P Being Affected by Events
Event
T
P
Power on
1
1
WDTC instruction
1
1
WDT time-out
SLEP instruction
0
1
*P
Wake-Up on pin change during SLEEP2 mode
P
P
0
* P: Previous value before reset
4.8 Interrupt
The EM78P451 has the following interrupts.
1. /TCC overflow interrupt
2. External interrupt (/INT)
3. Serial Peripheral Interface (SPI) transmission completed interrupt.
4. Timer1 comparator completed interrupt.
R3F is the interrupt status register, which records the interrupt request in flag bit. IOCF
is the interrupt mask register. Global interrupt is enabled by ENI instruction and is
disabled by DISI instruction. When one of the interrupts (if enabled) is generated, will
cause the next instruction to be fetched from address 001H. Once in the interrupt
service routine the source of the interrupt can be determined by polling the flag bits in
36 •
Product Specification (V1.1) 06.30.2003
(This specification is subject to change without further notice)
EM78P451
8-Bit Microcontroller with OTP ROM
the R3F register. The interrupt flag bit must be cleared by software before leaving the
interrupt service routine and enabling interrupts to avoid recursive interrupts.
The flag in the Interrupt Status Register (R3F) is set regardless of the status of its mask
bit or the execution of ENI instruction. Note that reading R3F will obtain the output of
logic AND of R3F and IOCF (refer to Fig. 17). The RETI instruction exits interrupt
routine and enables the global interrupt (execution of ENI instruction).
When an interrupt is generated by INT instruction (if enabled), it causes the next
instruction to be fetched from address 002H.
IRQn
P Q
R
C
CLK
L Q
D
/IRQn
interrupt
IRQm
RFRD
R3F
ENI/DISI
P
D
R
C CLK
Q L
IOD
Q
IOCFW R
IOCF
RESET
IOCF RD
RFW R
Fig. 17 Interrupt Input Circuit
4.9 Oscillator
4.9.1 Oscillator Modes
The EM78P451 can operate in four different oscillator modes. There are high XTAL
(HXT) oscillator mode, low XTAL (LXT) oscillator mode, External RC oscillator mode
(ERC), and Internal C、External R oscillator modes. User can select one of them by
programming MS, RCT, HLF and HLP in the Code Option Register. Table 9 depicts
how these three modes are defined.
Table 9 Oscillator Modes by MS, IRC, RCT.
Mode
High XTAL Oscillator
Low XTAL Oscillator
External RC Oscillator
External R and Internal C Oscillator
MS
RCT
HLF
HLP
1
1
0
0
X
X
1
0
1
0
X
X
X
0
X
X
NOTE
X: Don’t care
Product Specification (V1.1) 06.30.2003
(This specification is subject to change without further notice)
• 37
EM78P451
8-Bit Microcontroller with OTP ROM
4.9.2 Crystal Oscillator/Ceramic Resonators (XTAL)
EM78P451 can be driven by an external clock signal through the OSCI pin as shown in
Fig 18 below. In the most applications, pin OSCI and pin OSCO is connected with a
crystal or ceramic resonator to generate oscillation. Fig 19 depicts such circuit. Table
10 provides the recommended values of C1 and C2. Since each resonator has its own
attribute, user should refer to its specification for appropriate values of C1 and C2. RS,
a serial resistor may be necessary for AT strip cut crystal or low frequency mode.
Ext. Clock
OSCI
OSCO
EM 78P451
Fig. 18 Circuit for External Clock Input
C1
OSCI
EM 78P451
XTAL
OSCO
RS
C2
Fig. 19 Circuit for Crystal/Resonator
Table 10 Capacitor Selection Guide for Crystal Oscillator Ceramic Resonators
Oscillator Type
Ceramic Resonator
Frequency Mode
HXT
LXT
Crystal Oscillator
HXT
38 •
Frequency
C1 (pF)
C2 (pF)
455 KHz
1.0 MHz
2.0 MHz
4.0 MHz
32.768 KHz
100 KHz
200 KHz
455 KHz
1.0 MHz
2.0 MHz
4.0 MHz
10~150
40~80
20~40
10~30
25
25
25
20~40
15~30
15
15
10~150
40~80
20~40
10~30
15
25
25
20~150
15~30
15
15
Product Specification (V1.1) 06.30.2003
(This specification is subject to change without further notice)
EM78P451
8-Bit Microcontroller with OTP ROM
330
330
C
OSCI
7404
7404
7404
EM 78P451
XTAL
Fig. 20 Circuit for Crystal/Resonator-Series Mode
4.7K
10K
VDD
O SCI
EM 78P451
7404
7404
10K
XTAL
C1
C2
Fig. 21 Circuit for Crystal/Resonator-Parallel Mode
4.9.3 RC Oscillator Mode
For some applications that do not need a very precise timing calculation, the RC
oscillator (Fig 22 & Fig 23) offers a lot of cost savings. Nevertheless, it should be noted
that the frequency of the RC oscillator is influenced by the supply voltage, the values of
the resistor (Rext), the capacitor (Cext), and even by the operation temperature.
Moreover, the frequency also changes slightly from one chip to another due to the
manufacturing process variation.
In order to maintain a stable system frequency, the values of the Cext should not be
less than 20pF, and that the value of Rext should not be greater than 1 M ohm. If they
cannot be kept in this range, the frequency is easily affected by noise, humidity, and
leakage.
The smaller the Rext in the RC oscillator, the faster its frequency will be. On the
contrary, for very low Rext values, for instance, 1 KΩ, the oscillator becomes unstable
because the NMOS cannot discharge the current of the capacitance correctly.
Based on the reasons above, it must be kept in mind that all of the supply voltage, the
operation temperature, the components of the RC oscillator, the package types, the
way the PCB is layout, will affect the system frequency.
Product Specification (V1.1) 06.30.2003
(This specification is subject to change without further notice)
• 39
EM78P451
8-Bit Microcontroller with OTP ROM
VCC
Rext
OSCI
EM 78P451
Cext
Fig. 22 Circuit for External RC Oscillator Mode
VCC
Rext
OSCI
EM 78P451
Fig. 23 Circuit for External R, Internal C Oscillator Mode
Calibrate frequency of External RC oscillator (For reference only)
C ext
20pF
100pF
300pF
40 •
R ext
Fosc @5.0V,25℃
3.3K
3.4MHz
5.1K
2.2MHz
10K
1.3MHz
100K
144KHz
3.3K
1.39MHz
5.1K
935KHz
10K
500KHz
100K
54.5KHz
3.3K
740KHz
5.1K
490KHz
10K
255KHz
100K
28KHz
Product Specification (V1.1) 06.30.2003
(This specification is subject to change without further notice)
EM78P451
8-Bit Microcontroller with OTP ROM
Internal C, external R Table (For reference only)
External R (Ohm)
Fosc @5.0V, 25℃ (Hz)
10K
15K
20K
30K
51K
100K
150K
200K
510K
2M
3.3M
12M
7.7M
5.7M
3.65M
2.24M
1.14M
749K
559K
214K
56K
32.8K
4.10 Code Option Register
Address 12
0xFFF
11
10
9
MS ENWDT CLKS PTB
8
7
6
HLF
RCT
HLP
5
4
DEL0 DEL1
3
2
1
0
ID3
ID2
ID1
ID0
Bit 12 (MS): Oscillator type selection.
0: RC type
1: XTAL type
Bit 11 (ENWDT): Watchdog Timer enabled.
0: Enable
1: Disable
Bit 10 (CLKS): Clocks of each instruction cycle.
0: Two clocks
1: Four clocks
Bit 9 (PTB): Protect bit.
0: Protect enabled
1: Protect disabled
Bit 8 (HLF): XTAL frequency selection.
0: Low frequency (32.768KHz)
1: High frequency
This bit is useful only when Bit 12 (MS) is 1. When MS is 0, HLF must be
0.
Product Specification (V1.1) 06.30.2003
(This specification is subject to change without further notice)
• 41
EM78P451
8-Bit Microcontroller with OTP ROM
Bit 7 (RCT): Resistor Capacitor.
0: internal RC
1: external RC
Bit 6 (HLP): Power consumption selection.
0: Low power
1: High power
Bit 5 ~ Bit 4: DEL1 and DEL0 (SDI) input delay time options.
DEL 1
DEL 0
Delay time
1
0
1
1
1
0
0 ns
50 ns
100 ns
Bit3~0 (ID): User’s ID code.
4.11 Instruction Set
Each instruction in the instruction set is a 13-bit word divided into an OP code and one
or more operands. All instructions are executed within one single instruction cycle
(consisting of 2 oscillator periods), unless the program counter is changed by(a) Executing the instruction "MOV R2,A", "ADD R2,A", "TBL", or any other instructions
that write to R2 (e.g. "SUB R2,A", "BS R2,6", "CLR R2", ⋅⋅⋅⋅).
(b) execute CALL, RET, RETI, RETL, JMP, Conditional skip (JBS, JBC, JZ, JZA, DJZ,
DJZA) which were tested to be true.
Under these cases, the execution takes two instruction cycles.
In addition, the instruction set has the following features:
(1). Every bit of any register can be set, cleared, or tested directly.
(2). The I/O register can be regarded as general register. That is, the same instruction
can operate on I/O register.
The symbol "R" represents a register designator that specifies which one of the
registers (including operational registers and general purpose registers) is to be utilized
by the instruction. Bits 6 and 7 in R4 determine the selected register bank. "b"
represents a bit field designator that selects the value for the bit located in the register
"R" and affects operation. "k" represents an 8 or 10-bit constant or literal value.
42 •
Product Specification (V1.1) 06.30.2003
(This specification is subject to change without further notice)
EM78P451
8-Bit Microcontroller with OTP ROM
INSTRUCTION BINARY
HEX
MNEMONIC
0 0000 0000 0000
0000
NOP
No Operation
None
0 0000 0000 0001
0001
DAA
Decimal Adjust A
C
0 0000 0000 0010
0002
CONTW
A → CONT
None
0 0000 0000 0011
0003
SLEP
0 → WDT, Stop oscillator
T,P
0 0000 0000 0100
0004
WDTC
0 → WDT
T,P
0 0000 0000 rrrr
000r
IOW R
A → IOCR
None <Note1>
0 0000 0001 0000
0010
ENI
Enable Interrupt
None
0 0000 0001 0001
0011
DISI
Disable Interrupt
None
0 0000 0001 0010
0012
RET
[Top of Stack] → PC
None
0 0000 0001 0011
0013
RETI
[Top of Stack] → PC,
Enable Interrupt
None
0 0000 0001 0100
0014
CONTR
CONT → A
None
0 0000 0001 rrrr
001r
IOR R
IOCR → A
None <Note1>
0 0000 0010 0000
0020
TBL
R2+A → R2,
Bits 8~9 of R2 unchanged
Z,C,DC
0 0000 01rr rrrr
00rr
MOV R,A
A→R
None
0 0000 1000 0000
0080
CLRA
0→A
Z
0 0000 11rr rrrr
00rr
CLR R
0→R
Z
0 0001 00rr rrrr
01rr
SUB A,R
R-A → A
Z,C,DC
0 0001 01rr rrrr
01rr
SUB R,A
R-A → R
Z,C,DC
0 0001 10rr rrrr
01rr
DECA R
R-1 → A
Z
0 0001 11rr rrrr
01rr
DEC R
R-1 → R
Z
0 0010 00rr rrrr
02rr
OR A,R
A ∨ VR → A
Z
0 0010 01rr rrrr
02rr
OR R,A
A ∨ VR → R
Z
0 0010 10rr rrrr
02rr
AND A,R
A&R→A
Z
0 0010 11rr rrrr
02rr
AND R,A
A&R→R
Z
0 0011 00rr rrrr
03rr
XOR A,R
A⊕R→A
Z
0 0011 01rr rrrr
03rr
XOR R,A
A⊕R→R
Z
0 0011 10rr rrrr
03rr
ADD A,R
A+R→A
Z,C,DC
0 0011 11rr rrrr
03rr
ADD R,A
A+R→R
Z,C,DC
0 0100 00rr rrrr
04rr
MOV A,R
R→A
Z
0 0100 01rr rrrr
04rr
MOV R,R
R→R
Z
0 0100 10rr rrrr
04rr
COMA R
/R → A
Z
0 0100 11rr rrrr
04rr
COM R
/R → R
Z
0 0101 00rr rrrr
05rr
INCA R
R+1 → A
Z
0 0101 01rr rrrr
05rr
INC R
R+1 → R
Z
0 0101 10rr rrrr
05rr
DJZA R
R-1 → A, skip if zero
None
0 0101 11rr rrrr
05rr
DJZ R
R-1 → R, skip if zero
None
0 0110 00rr rrrr
06rr
RRCA R
R(n) → A(n-1),
C
Product Specification (V1.1) 06.30.2003
(This specification is subject to change without further notice)
OPERATION
STATUS AFFECTED
• 43
EM78P451
8-Bit Microcontroller with OTP ROM
INSTRUCTION BINARY
HEX
MNEMONIC
OPERATION
STATUS AFFECTED
R(0) → C, C → A(7)
0 0110 01rr rrrr
06rr
RRC R
0 0110 10rr rrrr
06rr
RLCA R
0 0110 11rr rrrr
06rr
RLC R
0 0111 00rr rrrr
07rr
SWAPA R
0 0111 01rr rrrr
07rr
SWAP R
0 0111 10rr rrrr
07rr
0 0111 11rr rrrr
R(n) → R(n-1),
R(0) → C, C → R(7)
R(n) → A(n+1),
R(7) → C, C → A(0)
R(n) → R(n+1),
R(7) → C, C → R(0)
R(0-3) → A(4-7),
R(4-7) → A(0-3)
C
C
C
None
R(0-3) ↔ R(4-7)
None
JZA R
R+1 → A, skip if zero
None
07rr
JZ R
R+1 → R, skip if zero
None
0 100b bbrr rrrr
0xxx
BC R,b
0 → R(b)
None <Note2>
0 101b bbrr rrrr
0xxx
BS R,b
1 → R(b)
None <Note3>
0 110b bbrr rrrr
0xxx
JBC R,b
if R(b)=0, skip
None
0 111b bbrr rrrr
0xxx
JBS R,b
if R(b)=1, skip
None
1 00kk kkkk kkkk
1kkk
CALL k
PC+1 → [SP],
(Page, k) → PC
None
1 01kk kkkk kkkk
1kkk
JMP k
(Page, k) → PC
None
1 1000 kkkk kkkk
18kk
MOV A,k
k→A
None
1 1001 kkkk kkkk
19kk
OR A,k
A∨k→A
Z
1 1010 kkkk kkkk
1Akk
AND A,k
A&k→A
Z
1 1011 kkkk kkkk
1Bkk
XOR A,k
A⊕k→A
Z
1 1100 kkkk kkkk
1Ckk
RETL k
k → A, [Top of Stack] → PC
None
1 1101 kkkk kkkk
1Dkk
SUB A,k
k-A → A
Z,C,DC
1 1110 0000 0010
1E02
INT
PC+1 → [SP], 002H → PC
None
1 1111 kkkk kkkk
1Fkk
ADD A,k
k+A → A
Z,C,DC
NOTE
This instruction is applicable to IOC5 ~ IOC9, IOCD~IOCF only.
This instruction is not recommended for RF operation.
This instruction cannot operate on R3F.
44 •
Product Specification (V1.1) 06.30.2003
(This specification is subject to change without further notice)
EM78P451
8-Bit Microcontroller with OTP ROM
4.12 Timing Diagrams
AC Test Input/O utput W aveform
2.4
2.0
0.8
TEST POINTS
2.0
0.8
0.4
AC Testing : Input is driven at 2.4V for logic "1",and 0.4V for logic "0".Tim ing m easurem ents are
m ade at 2.0V for logic "1",and 0.8V for logic "0".
RESET Tim ing (CLK="0")
NOP
Instruction 1
Executed
CLK
/RESET
T drh
TCC Input Tim ing (CLKS="0")
Tins
CLK
TCC
Ttcc
Product Specification (V1.1) 06.30.2003
(This specification is subject to change without further notice)
• 45
EM78P451
8-Bit Microcontroller with OTP ROM
5
ABSOLUTE MAXIMUM RATING
Items
Temperature under bias
Storage temperature
0°C
to
70°C
-65°C
to
150°C
Input voltage
-0.3V
to
+6.0V
Output voltage
-0.3V
to
+6.0V
DC
to
20MHz
Operating Frequency (2clk)
6
Rating
ELECTRICAL CHARACTERISTICS
6.1 DC Characteristic
(Ta=0°C~70°C, VDD=5V±5%, VSS=0V)
Symbol
Parameter
Condition
Min
XTAL VDD to 2.3V
FXT
XTAL VDD to 3V
Two clocks
XTAL VDD to 5V
RC VDD to 2.3V
FRC
RC VDD to 3V
Two clocks
RC VDD to 5V
IIL
VIH1
VIL1
VIHX1
VILX1
VIH2
VIL2
VIHX2
VILX2
VOH1
VOH2
46 •
Input Leakage Current
Input High Voltage
VDD=5V)
Input Low Voltage
(VDD=5V)
Clock Input High Voltage
(VDD=5V)
Clock Input Low Voltage
(VDD=5V)
Input High
Voltage(VDD=3V)
Input Low Voltage
(VDD=3V)
Clock Input High Voltage
(VDD=3V)
Clock Input Low Voltage
(VDD=3V)
Output High Voltage
(Ports 5,6,8, P74~P77,
P90~P92,P95~P97,and
PF5~PF7)
Output High Voltage
(P70~P72)
Typ
Max
DC
4
DC
8
DC
20
DC
4
DC
4
DC
4
±1
VIN = VDD, VSS
2.0
2.5
1.0
1.5
1.5
0.6
2.4
2
V
V
V
V
OSCI
S7=1(IOCD Register bit7),
IOH = -7.0mA
µA
V
0.4
IOH = -8.0mA
MHz
V
OSCI
OSCI
MHz
V
0.8
OSCI
Unit
V
V
2.4
V
Product Specification (V1.1) 06.30.2003
(This specification is subject to change without further notice)
EM78P451
8-Bit Microcontroller with OTP ROM
Symbol
VOH3
VOL1
VOL2
VOL3
VOL4
Parameter
Output High Voltage
(P93/SDO,P94/SCK)
Output Low Voltage
(Ports 5,6,8, P74~P77,
P90~P92,P95~P97,and
PF5~PF7))
Output Low Voltage
(P70~P72)
Output Low Voltage
(P93/SDO, P94/SCK)
Output Low Voltage
(P74~P77)
Condition
Min
S7=0(IOCD Register bit7),
IOH = -7.0mA
2.4
IOH = -5.0mA
2.4
S7=1(IOCD Register bit7),
IOH = 10.0mA
S7=0(IOCD Register bit7),
IOH = 10.0mA
V
0.4
IOL = 15.0mA
0.4
IPH2
Pull-high active, input pin at VSS
V
0.8
0.4
Pull-high active, input pin at VSS
Operating supply current
0.4
IOL = 7.0mA
Pull-high current
(P74,P75)
ICC
Unit
0.4
Pull-high current
Power down current
Max
V
IOL = 5.0mA
IPH
ISB
Typ
-50
-100
-240
1
V
µA
mA
All input and I/O pin at VDD,
output pin floating, WDT enabled
/RESET="High",
Fosc=1.84324MHz (CK2="0"),
output pin floating
10
µA
3
mA
6.2 AC Characteristic
(Ta=0°C~70°C, VDD=5V±5%, VSS=0V)
Symbol
Parameter
Dclk
Input CLK duty cycle
Tins
Instruction cycle time
(CK2="0")
Ttcc
TCC input period
Twdt
Watchdog timer period
Tdrh
Device reset hold period
Conditions
RC Type
Min
Typ
Max
Unit
45
50
55
%
DC
ns
500
(Tins+20)/N*
Ta=25°C
Ta=25°C
ns
18
18
3
ms
ms
N= selected prescaler ratio.
3
NOTE: Vdd = 5V, set up time period = 16.2ms ± 5%
Vdd = 3V, set up time period = 18.0ms ± 5%
Product Specification (V1.1) 06.30.2003
(This specification is subject to change without further notice)
• 47
EM78P451
8-Bit Microcontroller with OTP ROM
7
Application Circuit
EM78P451
48 •
Product Specification (V1.1) 06.30.2003
(This specification is subject to change without further notice)
EM78P451
8-Bit Microcontroller with OTP ROM
APPENDIX
A Package Types
OTP MCU
Package Type
Pin Count
Package Size
EM78P451P
DIP
40
600 mil
EM78P451AQ
QFP
44
Product Specification (V1.1) 06.30.2003
(This specification is subject to change without further notice)
• 49
EM78P451
8-Bit Microcontroller with OTP ROM
50 •
Product Specification (V1.1) 06.30.2003
(This specification is subject to change without further notice)