TOSHIBA TMP88CU74F

TMP88CU74
◆ Time base timer
◆ Divider output function
◆ Watchdog timer
• Interrupt source/reset output (programmable)
◆ 8-bit serial interface: 1 channel
• With 8 bytes transmit/receive data buffer
• Internal/External serial clock, and 4/8-bit mode
◆ Serial bus interface
• 8-bit SIO/I2C bus mode
◆ 8-bit successive approximate type AD converter with sample and hold
• Analog inputs: 12 channels conversion time:
23 μs at 8 MHz (High-speed conversion mode),
59 μs at 12.5 MHz (Low-speed conversion mode)
◆ Vacuum fluorescent tube driver (Automatic display)
• High breakdown voltage ports (Max 40 V × 37 bits)
• Programmable grid scan output
◆ Dual clock operation
• Single/Dual-clock mode (selection)
◆ Five power saving operating modes
• STOP mode: Oscillation stops. Battery/Capacitor back-up. Release by stop pin input.
• SLOW mode: Low power consumption operation using low-frequency clock.
• IDLE1 mode: CPU stops, and Peripherals operate using high-frequency clock. Release by
interrupts.
• IDLE2 mode: CPU stops, and Peripherals operate using high-and low-frequency clock. Release
by interrupts.
• SLEEP mode: CPU stops, and Peripherals operate using low-frequency clock. Release by
interrupts.
◆ Wide operating voltage: 2.7 to 5.5 V at 32.8 kHz, 4.5 to 5.5 V at 12.5 MHz/32.8 kHz
◆ Emulation Pod: BM88CU74F0A
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1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
(V24) P90
(V25) P91
(V26) P92
(V27) P93
(V28) P94
(V29) P95
(V30) P96
(V31) P97
(V32) PD0
(V33) PD1
(V34) PD2
(V35) PD3
(V36) PD4
VKK
( SCK1 ) P00
(SI1) P01
(SO1) P02
P03
P04
P05
P06
P07
VSS
XOUT
XIN
RESET
(XTOUT) P22
(XTIN) P21
TEST
(STOP/INT5) P20
(INT0) P10
(INT1) P11
(TC2/PPG) P12
(DVO) P13
(PDO/PWM) P14
(TC1/INT3) P15
(INT2) P16
(INT4/TC3) P17
(SCL/SI0) P30
(SDA/SO0) P31
64
63
62
61
60
59
58
57
56
55
54
53
52
51
50
49
48
47
46
45
44
43
42
41
P87 (V23)
P86 (V22)
P85 (V21)
P84 (V20)
P83 (V19)
P82 (V18)
P81 (V17)
P80 (V16)
P77 (V15)
P76 (V14)
P75 (V13)
P74 (V12)
P73 (V11)
P72 (V10)
P71 (V9)
P70 (V8)
P67 (V7)
P66 (V6)
P65 (V5)
P64 (V4)
P63 (V3)
P62 (V2)
P61 (V1)
P60 (V0)
TMP88CU74
Pin Assignments (Top View)
P-QFP80-1420-0.80B
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
40
39
38
37
36
35
34
33
32
31
30
29
28
27
26
25
88CU74-3
VDD
VAREF
VASS
P53 (AIN11)
P52 (AIN10)
P51 (AIN9)
P50 (AIN8)
P47 (AIN7)
P46 (AIN6)
P45 (AIN5)
P44 (AIN4)
P43 (AIN3)
P42 (AIN2)
P41 (AIN1)
P40 (AIN0)
P32 (SCK 0 )
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TMP88CU74
Block Diagram
I/O port
Power Supply
VDD
VSS
VFT Power
Supply
VKK
P67
to
P60
P77
to
P70
P87
to
P80
P97
to
P90
PD4
to
PD0
P6
P7
P8
P9
PD
Vacuum Fluorescent Tube Driver Circuit
Address/Data Bus
Reset
I/O pin
Test pin
RESET
TLCS-870/X
CPU Core
System Controller
TEST
Timing Generator
XIN
XOUT
High frequ
Low frequ
P2
P22 VAREF
to
VASS
P20
I/O port
Time Base
Timer
Clock
Generator
8 bit AD
converter
Analog
Reference
Voltage
Program Memory
(ROM)
Interrupt control circuit
Stanby Controller
Xtal
Connecting
Pins
Data Memory
(RAM)
16-bit
Timer/Counters
TC1
TC2
8-bit
Timer/Counters
TC3
TC4
Serial bus
Interfaces
SIO1 I2C bus
Watchdog
Timer
P4
P5
P47 (AIN7) P53 (AIN11)
to
to
P40 (AIN0) P50 (AIN8)
P1
P0
P3
P17
to
P10
P07
to
P00
P32
to
P30
(Analog inputs)
I/O port
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Pin Functions (1/2)
Pin Name
Input/Output
P07 to P03
I/O
P02 (SO1)
I/O (Output)
P01 (SI1)
P00 ( SCK1 )
I/O (Input)
I/O (I/O)
P17 (INT4/TC3)
P16 (INT2)
I/O (Input)
P15 (INT3/TC1)
P14 ( PDO / PWM )
I/O (Output)
P13 ( DVO )
I/O (Output)
P12 (TC2/ PPG )
P11 (INT1)
P10 ( INT0 )
P22 (XTOUT)
I/O (Output)
I/O (Input)
I/O (Input)
P31 (SDA/SO0)
I/O (I/O/Output)
P30 (SCL/SI0)
I/O (I/O/Input)
P47 (AIN7)
to P40 (AIN0)
I/O (Input)
P53 (AIN13)
to P50 (AIN8)
I/O (Input)
P67 (V7) to P60 (V0)
P77 (V15) to P70 (V8)
P87 (V23) to P80 (V16)
P97 (V31) to P90 (V24)
I/O (Output)
SIO1 Serial data Output
SIO1 Serial data Input
SIO1 Serial clock input/output
External interrupt 4 input or
Timer Counter 3 input
External interrupt 2 input
External interrupt 3 input or Timer
Counter 1 input
PWM output or programmable divider output
Divider output
Timer counter input 2 or programmable pulse
generator output
External interrupt input 1
I/O (Input)
P20 ( INT5 / STOP )
PD4(V36) to PD0 (V32)
Two 8-bit programmable input/output
ports (tri-state).
Each bit of these ports can be
individually configured as an input or
an output under software control.
During reset, all bits are configured
as inputs.
When used as a PPG output or a
divider output, the output latch must
be set to “1”.
I/O (I/O)
P21 (XTIN)
P32 ( SCK 0 )
Function
External interrupt input 0
3-bit input/output port with latch.
When used as an input port, a
resonator connecting pin, an
external interrupt input, or a STOP
mode release input, the output latch
must be set to “1”.
Resonator connecting pins (32.8 kHz).
For inputting external clock, XTIN is used and
XTOUT is opened.
External interrupt input 5 or STOP mode release
signal input
3-bit programmable input/output port
(tri-state/programmable open drain). SIO0 clock input/output
Each bit of the port can be individully
configured as an input or an output
under software control.
I2C bus data input/output or SIO0 data output
When used as a serial interface
output, the output latch must be set
to “1”.
I2C bus clock input/output or SIO0 data input
8/4-bit programmable input/output
port (tri-state).
Each bit of the port can be
individually configured as an input or AD converter analog inputs
output under software control.
When used as an analog input set to
input mode.
8-bit high breakdown voltage output
ports with the latch.
When used as an vacuum
fluorescent tube driver output, the
output latch must be cleared to “0”.
5-bit high breakdown voltage output
ports with the latch.
When used as an vacuum
fluorescent tube driver output, the
latch must be cleared to “0”.
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VTF output
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Pin Functions (2/2)
Pin Name
Input/Output
Function
XIN, XOUT
Input/Output
Resonator connecting pins for high-frequency clock.
For inputting external clock, XIN is used an XOUT is opened.
RESET
Input/Output
Reset signal input or watchdog timer output/address-reset output/system clock reset output.
TEST
Input
VDD, VSS
VKK
VAREF, VASS
Test pin for out-going teset. Be tied to low.
+5 V, 0 V (GND)
Power Supply
Vacuum fluore scent tube driver voltage pin.
Analog reference voltage input (High, Low)
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TMP88CU74
Operational Description
1.
CPU Core Functions
The CPU core consists of a CPU, a system clock controller, an interrupt controller, and a
watchdog timer.
This section provides a description of the CPU core, the program memory (ROM), the data
memory (RAM), and the reset circuit.
1.1
Memory Address Map
TLCS-870/X Series, the memory is organized 4 address spaces (ROM, RAM, SFR, and DBR).
Figure 1.1.1 shows the memory address maps of the TMP88CU74. It uses a memory mapped
I/O system, and all I/O registers are mapped in the SFR/DBR address spaces. There are 16
banks of general-purpose registers.
00000H
SFR
64 bytes
0003F
00040
128 bytes
000BF
000C0
Register banks
(8 registers × 16 banks)
RAM
1920 bytes
0083F
00F80
128 bytes
DBR
00FFF
ROM: Read Only Memory includes:
Program memory
Vector table
RAM: Random Access Memory includes:
Data memory
Stack
General-purpose register banks
SFR: Special Function Register includes:
I/O ports
Peripheral control registers
Peripheral status registers
System control registers
Interrupt control registers
Program Status Word
DBR: Data Buffer Register includes:
SIO data buffer
VFT display data buffer
04000
98304
bytes
1BFFF
ROM
FFF00
FFF3F
FFF40
FFF7F
FFF80
FFFBF
FFFC0
FFFFF
64 bytes
64 bytes
Vector table for vector call
instructions (16 vectors)
64 bytes
64 bytes
Vector table for interrupts/
Reset (16 vectors)
TMP88CU74
Figure 1.1.1 Memory Address Maps
1.2
Program Memory (ROM)
The TMP88CU74 has a 96 Kbytes (addresses 04000H to 1BFFFH) and 256 bytes (addresses
FFF00H to FFFFFH) of program memory (mask programmed ROM). Figure 1.1.1 shown in
Memory address maps.
Addresses FFF00H to FFFFFH in the program memory can also be used for special purposes.
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1.3
Data Memory (RAM)
The TMP88CU74 has 2 Kbytes of static RAM (address 00040H to 0083FH). The first 128
bytes (00040H to 000BFH) of the internal RAM are also used as general-purpose register
banks.
The data memory contents become unstable when the power supply is turned on; therefore,
the data memory should be initialized by an initialization routine.
Example: Clears RAM to “00H” except the bank 0.
LD
HL, 00048H
LD
A, H
LD
BC, 03F7H
SRAMCLR:
LD
(HL+), A
DEC
BC
JRS
F, SRAMCLR
Note:
1.4
;
;
;
Sets start address to HL register pair
Sets initial data (00H) to A register
Sets number of byte to BC register pair
The general-purpose registers are mapped in the RAM; therefore, do not clear RAM at the
current bank addresses.
System Clock Controller
The system clock controller consists of a clock generator, a timing generator, and a stand-by
controller.
Timing generator control register
TBTCR
Clock
generator
00036H
fc
XIN
High-frequency
clock oscillator
Stand-by controller
Timing generator
XOUT
XTIN
System clocks
Low-frequency
clock oscillator
00038H
fs
00039H
SYSCR1
XTOUT
Clock generator control
SYSCR2
System control registers
Figure 1.4.1 System Clock Controller
1.4.1
Clock Generator
The clock generator generates the basic clock which provides the system clocks supplied
to the CPU core and peripheral hardware. It contains two oscillation circuits: one for the
high-frequency clock and one for the low-frequency clock. Power consumption can be
reduced by switching of the system clock controller to low-power operation based on the
low-frequency clock.
The high-frequency (fc) and low-frequency (fs) clocks can easily be obtained by connecting
a resonator between the XIN/XOUT and XTIN/XTOUT pins, respectively. Clock input from
an external oscillator is also possible.
In this case, external clock is applied to XIN/XTIN pin with XOUT/XTOUT pin not
connected. The TMP88CU74 are not provided an RC oscillation.
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Low-frequency clock
High-frequency clock
XOUT
XIN
XIN
XOUT
XTIN
XTOUT
XTIN
(Open)
(a) Crystal/Ceramic resonator
XTOUT
(Open)
(b) External oscillator
(c) Crystal
(d) External oscillator
Figure 1.4.2 Examples of Resonator Connection
Note:
1.4.2
Accurate Adjustment of the Oscillation Frequency
Although no hardware to externally and directly monitor the basic clock pulse is not provided, the
oscillation frequency can be adjusted by making the program to output fixed frequency pulse to the
port with disabling all interrupts and watchdog timers, and monitoring this pulse. With a system
requiring adjustment of the oscillation frequency, the adjusting program must be created
beforehand.
Timing Generator
The timing generator generates the various system clocks supplied to the CPU core and
peripheral hardware from the basic clock (fc or fs). The timing generator provides the
following functions.
1. Generation of main system clock (fm)
2.
Generation of divider output ( DVO ) pulses
3.
Generation of source clocks for time base timer
4.
Generation of source clocks for watchdog timer
5.
Generation of internal source clocks for timer/counters TC1-TC6
6.
Generation of internal clocks for serial interfaces SIO and HSO
7.
Generation of source clocks for VFT driver circuit
8.
Generation of warm-up clocks for releasing STOP mode
9
Generation of a clock for releasing reset output
(1) Configuration of timing generator
The timing generator consists of a 3-stage prescaler, a 21-stage divider, a main
system clock generator, and machine cycle counters.
The clock fc/4 or fc/8, that is output from the 2nd stage or the 3rd stage of the
prescaler, can be selected as the clock to input to the 1st stage of the divider by DV1CK
(bit 5 in CGCR). Inputting fc/8 to the 1st stage of the divider operates the peripheral
circuit without the setting change when the operation clock is multiplied by 2.
(Example: 8 MHz to 12.5 MHz)
The DV1CK should be set the peripheral circuit prior to starting the peripheral
circuits. Do not change the set value after setting.
An input clock to the 7th stage of the divider depends on the operating mode, DV1CK
(bit 5 in DVCR), and DV7CK(bit 4 in TBTCR), that is shown in Table 1.4.1. As reset
and STOP mode started/canceled, The prescaler and the divider are cleared to “0”.
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Table 1.4.1 Input Clock to 7th Stage of the Divider
Single-clock Mode
NORMAL1, IDLE1 Mode
DV1CK = 0
DV1CK = 1
fc/28
fc/29
Dual-clock Mode
NORMAL2, IDLE2 Mode (SYSCK = 0)
DV7CK = 0
DV7CK = 1
DV1CK = 0
DV1CK = 1
fc/28
fc/29
SLOW,
SLEEP
Mode
(SYSCK = 1)
fs
fs
Note 1: Do not set DV7CK to “1” in the single clock mode.
Note 2: In SLOW and SLEEP mode, the input clock to the 1st stage of the divider is stopped; output from the
1st to 6th stages is also stopped.
fm
Main system clock generator
Machine cycle counters
SYSCK
DV7CK
DV1CK
Prescaler
High-frequency
clock
fc
Low-frequency
clock fs
fc
Divider
S
0 1 2
Divider
S
A
A
Y
B
Selector
Y
1 2 3 4 5 6
7 8 9 10 11 12 13 14 15 16 17 18 19 20 21
B
Selector
S
B0
B1
A0 Y0
A1 Y1
Timer/Counters
Selector
Stand-by
controller
Watchdog
timer
Time base
timer
Serial
interface
Vacuum
fluorescent
tube driver
circuit
Divider
output
Note: fm = fc or fs
Figure 1.4.3 Configuration of Timing Generator
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DVCR
(00030H)
7
6
5
“0”
“0”
DV1CK
DV1CK
4
3
2
1
0
(Initial value: **0* ****)
Selection of input clock to the 0: fc/4
1st stage of the divider
1: fc/8
R/W
Note 1: fc: High-frequency clock [Hz], *: Don't care
Note 2: Bit 4 to 0 in CGCR is always read in as “1” when a read instruction is executed.
Figure 1.4.4 Clock Gear Control Register
TBTCR
7
(00036H) (DVOEN)
DV7CK
6
5
4
(DVOCK)
3
2
1
DV7CK (TBTEN)
0
(Initial value: 0**0 0***)
(TBTCK)
Selection of input clock to the 0: fc/28 or fc/29 [Hz]
1: fs
7 th stage of the divide
R/W
Note 1: fc: High-frequency clock [Hz], *: Don't care
Note 2: Do not set DV7CK to “1” in the single clock mode.
Note 3: Do not set DV7CK to “1” before low-frequency clock is stable in the dual-clock mode.
Figure 1.4.5 Timing Generator Control Register
(2) Machine cycle
Instruction execution and peripheral hardware operation are synchronized with the
main system clock.
The minimum instruction execution unit is called an “machine cycle”. There are a
total of 15 different types of instructions for the TLCS-870/X Series: ranging from
1-cycle instructions which require one machine cycle for execution to 15-cycle
instructions which require 15 machine cycles for execution.
A machine cycle consists of 4 states (S0 to S3), and each state consists of one main
system clock.
1/fc or 1/fs [s]
Main system clock
(fm)
State
S0
S1
S2
S3
S0
S1
S2
S3
Machine cycle
0.32 μs at fc = 12.5 MHz
122 μs at fs = 32.8 kHz
Figure 1.4.6 Machine Cycle
1.4.3
Stand-by Controller
The stand-by controller starts and stops the oscillation circuits for the high-frequency
and low-frequency clocks, and switches the main system clock. There are two operating
modes: single-clock and dual-clock. These modes are controlled by the system control
registers (SYSCR1and SYSCR2).
Figure 1.4.7 shows the operating mode transition diagram and Figure 1.4.8 shows the
system control registers.
(1) Single-clock mode
Only the oscillation circuit for the high-frequency clock is used, and P21 (XTIN) and
P22 (XTOUT) pins are used as input/output ports. In the single-clock mode, the
machine cycle time is 4/fc [s] (0.32 μs at fc = 12.5 MHz).
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1.
NORMAL1 mode
In this mode, both the CPU core and on-chip peripherals operate using the
high-frequency clock. The TMP88CU74 is placed in this mode after reset.
2.
IDLE1 mode
In this mode, the internal oscillation circuit remains active. The CPU and the
watchdog timer are halted; however on-chip peripherals remain active (operate
using the high-frequency clock). IDLE1 mode is started by the system control
register 2 (SYSCR2), and IDLE1 mode is released to NORMAL1 mode by an
interrupt request from the on-chip peripherals or external interrupt inputs. When
the IMF (interrupt master enable flag) is “1” (interrupt enable), the execution will
resume with the acceptance of the interrupt, and the operation will return to
normal after the interrupt service is completed. When the IMF is “0” (interrupt
disable), the execution will resume with the instruction which follows the IDLE1
mode start instruction.
3.
STOP1 mode
In this mode, the internal oscillation circuit is turned off, causing all system
operations to be halted. The internal status immediately prior to the halt is held
with a lowest power consumption during STOP1 mode.
STOP1 mode is started by the system control register 1 (SYSCR1), and STOP1
mode is released by an inputting (either level-sensitive or edge-sensitive can be
programmably selected) to the STOP pin. After the warming-up period is
completed, the execution resumes with the instruction which follows the STOP1
mode start instruction.
(2) Dual-clock mode
Both the high-frequency and low-frequency oscillation circuits are used in this mode.
P21 (XTIN) and P22 (XTOUT) pins cannot be used as input/output ports. The main
system clock is obtained from the high-frequency clock in NORMAL2 and IDLE2
modes, and is obtained from the low-frequency clock in SLOW and SLEEP modes. The
machine cycle time is 4/fc [s] in the NORMAL2 and IDLE2 modes, and 4/fs [s] (122 μs
at fs = 32.8 kHz) in the SLOW and SLEEP modes.
The TLCS-870/X is placed in the signal-clock mode during reset. To use the
dual-clock mode, the low-frequency oscillator should be turned on by executing [SET
(SYSCR2), XTEN] instruction.
1.
NORMAL2 mode
In this mode, the CPU core operates using the high-frequency clock. On-chip
peripherals operate using the high-frequency clock and/or low-frequency clock.
2.
SLOW mode
This mode can be used to reduce power-consumption by turning off oscillation of
the high-frequency clock. The CPU core and on-chip peripherals operate using the
low-frequency clock.
Switching back and forth between NORMAL2 and SLOW modes are performed
by the system control register 2 (SYSCR2).
3.
IDLE2 mode
In this mode, the internal oscillation circuit remain active. The CPU and the
watchdog timer are halted; however, on-chip peripherals remain active (operate
using the high-frequency clock and/or the low-frequency clock). Starting and
releasing of IDLE2 mode are the same as for IDLE1 mode, except that operation
returns to NORMAL2 mode.
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4.
SLEEP mode
In this mode, the internal oscillation circuit of the low-frequency clock remains
active. The CPU, the watchdog timer, and the internal oscillation circuit of the
high-frequency clock are halted; however, on-chip peripherals remain active
(operate using the low-frequency clock). Starting and releasing of SLEEP mode
are the same as for IDLE1 mode, except that operation returns to SLOW mode.
5.
STOP2 mode
As in STOP1 mode, all system operations are halted in this mode.
As in NORMAL2 mode at the start, the operating mode returns to NORMAL2
mode, and as in SLOW mode at the start, it returns to SLOW mode after release.
RESET
Reset release
Instruction
Instruction
IDLE1
mode
NORMAL1
mode
STOP1
mode
Interrupt
Release input
Instruction
(a) Single-clock mode
Instruction
IDLE2
mode
NORMAL2
mode
Instruction
Interrupt
Instruction
STOP2
mode
Release
input
Instruction
SLEEP
mode
SLOW
mode
Instruction
Interrupt
(b) Dual-clock mode
Note: NORMAL1 and NORMAL2 modes are generically called NORMAL;
STOP1 and STOP2 are called STOP; and IDLE1, IDLE2 and SLEEP are called IDLE.
Frequency
Single-Clock
Operating Mode
RESET1
NORMAL1
IDLE1
STOP1
NORMAL2
Dual-Clock
HighLowfrequency frequency
IDLE2
Turning on
oscillation Turning off
oscillation
SLOW
SLEEP
STOP2
Turning off
oscillation
On-chip Peripherals
Reset
Reset
Operate
High-frequency
Turning on
oscillation
Turning off
oscillation
Machine Cycle Time
4/fc [s]
Operate
Halt
Turning off
oscillation
Turning on
oscillation
CPU Core
Halt
Halt
⎯
Operate
(High and/or Low)
4/fc [s]
Low-frequency
4/fs [s]
Halt
⎯
Low-frequency
Halt
Figure 1.4.7 Operating Mode Transition Diagram
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System Control Register 1
SYSCR1
7
6
(00038H)
STOP RELM
5
4
RETM
“1”
3
2
1
0
(Initial value: 0000 00**)
WUT
STOP
STOP mode start
0: CPU core and peripherals remain active
1: CPU core and peripherals are halted (start STOP mode)
RELM
Release method
for STOP mode
0: Edge-sensitive release
1: Level-sensitive release
RETM
Operating mode
after STOP mode
0: Return to NORMAL mode
1: Return to SLOW mode
R/W
Return to NORMAL mode
Warming-up time at releasing
STOP mode
WUT
00
01
10
11
DV1CK = 0
DV1CK = 1
3 × 216/fc
216/fc
3 × 214/fc
214/fc
3 × 217/fc
217/fc
3 × 215/fc
215/fc
Return to
SLOW mode
3 × 213/fc
213/fc
⎯
⎯
Note 1: Always set RETM to “0” when transiting from NORMAL mode to STOP mode. Always set RETM to “1” when
transiting from SLOW mode to STOP mode.
Note 2: When STOP mode is released with RESET pin input, a return is made to NORMAL mode regardless of the
RETM contents.
Note 3: fc: High-frequency clock [Hz]
fs: Low-frequency clock [Hz]
*: Don’t care
Note 4: Bits 1 and 0 in SYSCR1 are read in as undefined data when a read instruction is executed.
Note 5: Always set bit 4 in SYSCR1 to “1” when STOP mode is started.
System Control Register 2
7
6
SYSCR2
(00039H)
XEN
XTEN
5
4
SYSCK
IDLE
3
2
1
0
(Initial value: 1000 ****)
XEN
High-frequency oscillator
control
0: Turn off oscillation
1: Turn on oscillation
XTEN
Low-frequency oscillator
control
0: Turn off oscillation
1: Turn on oscillation
SYSCK
Main system clock select
(write)/main system clock
monitor (read)
0: High-frequency clock
1: Low-frequency clock
IDLE mode start
0: CPU and watchdog timer remain active
1: CPU and watchdog timer are stopped (start IDLE1 mode)
IDLE
R/W
Note 1: XEN and SYSCK are automatically overwritten in accordance with the contents of RETM (bit 5 in SYSCR1)
when STOP mode is released.
Note 2:
Note 3:
Note 4:
Note 5:
RETM
Operating mode after STOP mode
XTEN
0
1
NORMAL 1/2 mode
SLOW mode
1
0
SYSCK
0
1
Do not clear XEN to “0” when SYSCK = 0, and do not clear XTEN to “0” when SYSCK = 1.
A reset is applied ( RESET pin output goes low) if both XEN and XTEN are cleared to “0”.
*: Don’t care
Bits 3 to 0 in SYSCR2 are always read in as “1” when a read instruction is executed.
Figure 1.4.8 System Control Registers
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TMP88CU74
1.4.4
Operating Mode Control
(1) STOP mode (STOP1, STOP2)
STOP mode is controlled by the system control register 1 (SYSCR1) and the STOP
pin input. The STOP pin is also used both as a port P20 and an INT5 (external
interrupt input 5) pin. STOP mode is started by setting STOP (bit 7 in SYSCR1) to “1”.
During STOP mode, the following status is maintained.
1.
Oscillations are turned off, and all internal operations are halted.
2.
The data memory, registers, the program status word and port output latches are
all held in the status in effect before STOP mode was entered.
3.
The prescaler and the divider of the timing generator are cleared to “0”.
4.
The program counter holds the address of the instruction but one to the
instruction (e.g.[SET (SYSCR1).7]) which started STOP mode.
STOP mode includes a level-sensitive release mode and an edge-sensitive
release mode, either of which can be selected with the RELM (bit 6 in SYSCR1).
a.
Level-sensitive release mode (RELM = “1”)
In this mode, STOP mode is released by setting the STOP pin high. This mode
is used for capacitor back-up when the main power supply is cut off and long term
battery back-up.
When the STOP pin input is high, executing an instruction which starts STOP
mode will not place in STOP mode but instead will immediately start the release
sequence (warm-up). Thus, to start STOP mode in the level-sensitive release mode,
it is necessary for the program to first confirm that the STOP pin input is low. The
following two methods can be used for confirmation.
1.
Testing a port P20.
2.
Using an external interrupt input INT5 ( INT5 is a falling edge-sensitive input).
Example 1: Starting STOP mode from NORMAL mode by testing a port P20.
LD
(SYSCR1), 01010000B
; Sets up the level-sensitive release mode
SSTOPH:
TEST
(P2). 0
; Wait until the STOP pin input goes low
level
JRS
F, SSTOPH
SET
(SYSCR1). 7
; Starts STOP mode
Example 2: Starting STOP mode from NORMAL mode with an INT5 interrupt.
PINT5:
TEST
(P2). 0
; To reject noise, STOP mode does not
start if port P20 is at high
JRS
F, SINT5
LD
(SYSCR1), 01010000B
; Sets up the level-sensitive release mode.
SET
(SYSCR1). 7
; Starts STOP mode
SINT5:
RETI
88CU74-15
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TMP88CU74
VIH
STOP pin
XOUT pin
NORMAL operation
STOP operation
Warm-up
Confirm by program that the
STOP pin input is low and
start STOP mode.
NORMAL operation
STOP mode is released by the hardware.
Always released if the STOP
pin input is high.
Figure 1.4.9 Level-sensitive Release Mode
Note 1: Even if the STOP pin input is low after warming up start, the STOP mode is not restarted.
Note 2: In this case of changing to the level-sensitive mode from the edge-sensitive mode, the release
mode is not switched until a rising edge of the STOP pin input is detected.
b.
Edge-sensitive release mode (RELM = “0”)
In this mode, STOP mode is released by a rising edge of the STOP pin input.
This is used in applications where a relatively short program is executed
repeatedly at periodic intervals. This periodic signal (for example, a clock from a
low-power consumption oscillator) is input to the STOP pin. In the edge-sensitive
release mode, STOP mode is started even when the STOP pin input is high level.
Example: Starting STOP mode from NORMAL mode
LD
(SYSCR1), 10010000B
;
Starts after specified to the edge-sensitive
release mode
VIH
STOP pin
XOUT pin
NORMAL operation
STOP operation
Warm-up
STOP mode started
by the program.
NORMAL
operation
STOP operation
STOP mode is released by the hardware at the rising
edge of STOP pin input.
Figure 1.4.10 Edge-sensitive Release Mode
STOP mode is released by the following sequence.
1.
In the dual-clock mode, when returning to NORMAL2, both the high-frequency
and low-frequency clock oscillators are turned on; when returning to SLOW mode,
only the low-frequency clock oscillator is turned on. In the signal-clock mode, only
the high-frequency clock oscillator is turned on.
2.
A warming-up period is inserted to allow oscillation time to stabilize. During
warm-up, all internal operations remain halted. Four different warming-up times
can be selected with the WUT (bits 2 and 3 in SYSCR1) in accordance with the
resonator characteristics.
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TMP88CU74
3.
When the warming-up time has elapsed, normal operation resumes with the
instruction following the STOP mode start instruction (e.g. [SET (SYSCR1). 7]).
The start is made after the prescaler and the divider of the timing generator are
cleared to “0”.
Table 1.4.2 Warming-up Time Example (at fc = 12.5 MHz, fs = 32.8 kHz)
Warming-up Time [ms]
WUT
00
01
10
11
Note:
Return to NORMAL mode
DV1CK = 0
DV1CK = 1
15.729
5.243
3.932
1.311
31.457
10.486
7.864
2.621
Return to SLOW mode
750
250
⎯
⎯
The warming-up time is obtained by dividing the basic clock by the divider: therefore, the
warming-up time may include a certain amount of error if there is any fluctuation of the
oscillation frequency when STOP mode is released. Thus, the warming-up time must be
considered an approximate value.
STOP mode can also be released by inputting low level on the RESET pin,
which immediately performs the normal reset operation.
Note:
When STOP mode is released with a low hold voltage, the following cautions must be
observed.
The power supply voltage must be at the operating voltage level before releasing STOP
mode. The RESET pin input must also be “H” level, rising together with the power supply
voltage. In this case, if an external time constant circuit has been connected, the RESET
pin input voltage will increase at a slower pace than the power supply voltage. At this time,
there is a danger that a reset may occur if input voltage level of the RESET pin drops below
the non-inverting high-level input voltage (hysteresis input).
88CU74-17
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88CU74-18
Divider
Instruction
execution
Program
counter
Main system
clock
Oscillator
circuit
input
STOP pin
Divider
Instruction
execution
Program
counter
Main system
clock
Oscillator
circuit
0
Halt
Turn off
Turn on
Count up
a+3
Warming up
Turn on
n
a+2
n+2
n+3
n+4
0
a+5
a+6
0
Halt
(b) STOP mode release
1
2
3
Instruction at address a + 2 Instruction at address a + 3 Instruction at address a + 4
a+4
(a) STOP mode start (Example: Start with SET (SYSCR1). 7 instruction located at address a)
n+1
SET (SYSCR1). 7
a+3
Turn off
TMP88CU74
Figure 1.4.11 STOP Mode Start/Release
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TMP88CU74
(2) IDLE mode (IDLE1, IDLE2, SLEEP)
IDLE mode is controlled by the system control register 2 (SYSCR2) and maskable
interrupts. The following status is maintained during IDLE mode.
1.
Operation of the CPU and watchdog timer (WDT) is halted. On-chip peripherals
continue to operate.
2.
The data memory, CPU registers, program status word and port output latches
are all held in the status in effect before IDLE mode was entered.
3.
The program counter holds the address of the second instruction after the
instruction which starts IDLE mode.
Example: Starting IDLE mode.
SET
(SYSCR2). 4
;
IDLE ← 1
Starting IDLE mode
by instruction
CPU, WDT are halted
Yes
Reset input
Reset
No
No
Interrupt request
(Normal release mode)
No
Yes
IMF = 1
Yes (Interrupt release mode)
Interrupt processing
Execution of the instruction
which follows the IDLE
mode start instruction
Figure 1.4.12 IDLE Mode
IDLE mode includes a normal release mode and an interrupt release mode. Selection
is made with the interrupt master enable flag (IMF). Releasing IDLE mode returns
from IDLE1 to NORMAL1, from IDLE2 to NORMAL2, and from SLEEP to SLOW
mode.
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(I) Normal release mode (IMF = “0”)
IDLE mode is released by any interrupt source enabled by the individual
interrupt enable flag (EF) or an external interrupt 0 ( INT0 pin) request.
Execution resumes with the instruction following the IDLE mode start instruction
(e.g. [SET (SYSCR2), 4]. The interrupt latches (IL) of the interrupt source used for
releasing must be cleared to “0” by load instructions.
(II) Interrupt release mode (IMF = “1”)
IDLE mode is released and interrupt processing is started by any interrupt
source enabled with the individual interrupt enable flag (EF) or an external
interrupt 0 ( INT0 pin) request. After the interrupt is processed, the execution
resumes from the instruction following the instruction which starts IDLE mode.
IDLE mode can also be released by inputting low level on the RESET pin, which
immediately performs the reset operation. After reset, the TMP88CU74 is placed
in NORMAL 1 mode.
Note:
When a watchdog timer interrupt is generated immediately before IDLE mode
is started, the watchdog timer interrupt will be processed but IDLE mode will
not be started.
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88CU74-21
Halt
Watchdog
timer
Halt
Halt
Instruction
execution
Watchdog
timer
Program
counter
Interrupt
request
Main system
clock
Halt
Instruction
execution
Program
counter
Interrupt
request
Main system
clock
a+3
Operate
Watchdog
timer
(I) Normal release mode
(b) IDLE mode release
(II) Interrupt release mode
a+3
a+3
Halt
Operate
Operate
Acceptance of interrupt
Instruction at address a + 2
a+4
(a) IDLE mode start (Example: starting with the SET instruction located at address a)
SET (SYSCR2).4
a+2
Instruction
execution
Interrupt
request
Program
counter
Main system
clock
TMP88CU74
Figure 1.4.13 IDLE Mode Start/Release
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TMP88CU74
(3) SLOW mode
SLOW mode is controlled by the system control register 2 (SYSCR2) and the
timer/counter 2 (TC2).
a.
Switching from NORMAL2 mode to SLOW mode
First, set SYSCK (bit 5 in SYSCR2) to switch the main system clock to the
low-frequency clock. Next, clear XEN (bit 7 in SYSCR2) to turn off high-frequency
oscillation.
Note:
The high frequency clock can be continued oscillation in order to return to
NORMAL2 mode from SLOW mode quickly.
Always turn off oscillation of high frequency clock when switching from SLOW
mode to STOP mode.
When the low-frequency clock oscillation is unstable, wait until oscillation stabilizes
before performing the above operations. The timer/counter 2 (TC2) can conveniently be
used to confirm that low-frequency clock oscillation has stabilized.
Example 1: Switching from NORMAL2 mode to SLOW mode.
SET
(SYSCR2). 5
; SYSCK ← 1 (switches the main system
clock to the low-frequency clock)
CLR
(SYSCR2). 7
XEN ← 0 (turns off high-frequency
oscillation)
Example 2: Switching to the SLOW mode after low-frequency clock oscillation has stabilized.
LD
(TC2CR), 14H
; Sets TC2 mode (timer mode, source
clock: fs)
LDW
(TREG2), 8000H
; Sets warming-up time (according to Xtal
characteristics)
SET
(EIRH). EF14
; Enables INTTC2
LD
(TC2CR), 34H
; Starts TC2
PINTTC2:
VINTTC2:
LD
SET
(TC2CR), 10H
(SYSCR2). 5
;
;
CLR
(SYSCR2). 7
;
RETI
DL
PINTTC2
;
88CU74-22
Stops TC2
SYSCK ← 1 (switches the main system
clock to the low-frequency clock)
XEN ← 0 (turns off high-frequency
oscillation)
INTTC2 vector table
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TMP88CU74
b.
Switching from SLOW mode to NORMAL2 mode
First, set XEN (bit 7 in SYSCR2) to turn on the high-frequency oscillation.
When time for stabilization (warm-up) has been taken by the timer/counter 2
(TC2), clear SYSCK (bit 5 in SYSCR2) to switch the main system clock to the
high-frequency clock.
Note 1: After SYSCK is cleared to "0", executing the instructions is continued by the
low-frequency clock for the period synchronized with low-frequency and
high-frequency clocks.
High-frequency clock
Low-frequency clcok
Main system clock
SYSCK
Note 2: SLOW mode can also be released by inputting low level on the RESET pin, which
immediately performs the reset operation. After reset, the TMP88CU74 is placed in
NORMAL1 mode.
Example: Switching from SLOW mode to NORMAL2 mode
(fc = 12.5 MHz, warming-up time is 5.8 ms).
SET
(SYSCR2). 7
;
PINTTC2:
XEN ← 1 (turns on high-frequency
oscillation)
Sets TC2 mode (timer mode, source
clock: fc)
Sets the warming-up time (according to
frequency and Xtal characteristics)
Enables INTTC2
Starts TC2
LD
(TC2CR), 10H
;
LD
(TREG2 + 1), 0F8H
;
SET
LD
(EIRH). EF14
(TC2CR), 30H
;
;
LD
CLR
(TC2CR), 10H
(SYSCR2). 5
;
;
Stops TC2
SYSCK ← 0 (switches the main system
clock to the high-frequency clock)
PINTTC2
;
INTTC2 vector table
RETI
VINTTC2:
DL
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88CU74-24
Instruction
execution
XEN
SYSCK
Main system
clock
SLOW mode
Low-frequency
clock
SET (SYSCR2).5
SET (SYSCR2).7
NORMAL2
mode
High-frequency
clock
Instruction
execution
XEN
SYSCK
Main system
clock
Low-frequency
clock
High-frequency
clock
(b) Switching to the NORMAL2 mode
Warming up
CLR (SYSCR2).5
(a) Switching to the SLOW mode
Mode switching
CLR (SYSCR2).7
NORMAL2
mode
SLOW mode
Turn off
TMP88CU74
Figure 1.4.14 Switching between the NORMAL2 and SLOW Modes
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TMP88CU74
1.5
Interrupt Controller
The TMP88CU74 each have a total of 15 interrupt sources: 6 externals and 9 internals.
Nested interrupt control with priorities is also possible. Two of the internal sources are pseudo
non-maskable interrupts; the remainder are all maskable interrupts.
Interrupt latches (IL) that hold the interrupt requests are provided for interrupt sources.
Each interrupt vector is independent.
The interrupt latch is set to “1” when an interrupt request is generated and requests the CPU
to accept the interrupt. The acceptance of maskable interrupts can be selectively enabled and
disabled by the program using the interrupt master enable flag (IMF) and the individual
interrupt enable flags (EF). When two or more interrupts are generated simultaneously, the
interrupt is accepted in the highest priority order as determined by the hardware. Figure 1.5.1
shows the interrupt controller.
Table 1.5.1 Interrupt Sources
Interrupt Source
Internal/
External
Interrupt
Latch
Vector
Address
Non-Maskable
―
FFFFCH
Pseudo
non-maskable
―
FFFF8H
1
IL2
FFFF4H
2
Enable Condition
(Reset)
Priority
High
0
Internal
INTSW
(Software interrupt)
Internal
INTWDT
(Watchdog Timer interrupt)
External
INT0
(External interrupt 0)
IMF = 1, INT0EN = 1
IL3
FFFF0H
3
Internal
INTTC1
(16-bit TC1 interrupt)
IMF･EF4 = 1
IL4
FFFECH
4
External
INT1
(External interrupt 2)
IMF･EF5 = 1
IL5
FFFE8H
5
Internal
INTTBT
(Time Base Timer interrupt)
IMF･EF6 = 1
IL6
FFFE4H
6
External
INT2
(External interrupt 2)
IMF･EF7 = 1
IL7
FFFE0H
7
Internal
INTTC3
(8-bit TC3 interrupt)
IMF･EF8 = 1
IL8
FFFDCH
8
Internal
INTSIO1
(Serial Interface1 interrupt)
IMF･EF9 = 1
IL9
FFFD8H
9
Internal
INTTC4
(8-bit TC4 interrupt)
IMF･EF10 = 1
IL10
FFFD4H
10
External
INT3
(External interrupt 3)
IMF･EF11 = 1
IL11
FFFD0H
11
Internal
INTKEY
(Key scan interrupt)
IMF･EF12 = 1
IL12
FFFCCH
12
Internal
INTSIO2
(Serial interface2 interrupt)
IMF･EF13 = 1
IL13
FFFC8H
13
Internal
INTTC2
(16-bit TC2 interrupt)
IMF･EF14 = 1
IL14
FFFC4H
14
External
INT5
(External interrupt 5)
IMF･EF15 = 1
IL15
FFFC0H
Low 15
Note:
Before you change each enable flag (EF) and/or each interrupt latch (IL), be sure to clear the
interrupt master enable flag (IMF) to “0” (to disable interrupts).
a. After a DI instruction is executed
b. When an interrupt is accepted, IMF is automatically cleared to “0”. However, to enable
nested interrupts, change EF and/or IL before setting IMF to “1” (to enable interrupts).
If the individual enable flags (EF) and interrupt latches (IL) are set under conditions other
than the above, the proper operation cannot be guaranteed.
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TMP88CU74
(1) Interrupt latches (IL15 to 2)
Interrupt latches are provided for each source, except for a software interrupt. The latch
is set to “1” when an interrupt request is generated, and requests the CPU to accept the
interrupt. The latch is cleared to “0” just after the interrupt is accepted. All interrupt
latches are initialized to “0” during reset.
Interrupt latches are assigned to addresses 003CH and 003DH in the SFR. Each latch
can be cleared to “0” individually by an instruction; however, the read-modify-write
instruction such as bit manipulation or operation instructions cannot be used. Thus,
interrupt requests can be canceled and initialized by the program. Note that interrupt
latches cannot be set to “1” by any instruction.
The contents of interrupt latches can be read out by an instruction. Therefore, testing
interrupt requests by software is possible.
Example 1: Clears interrupt latches
LDW
(ILL), 1110100000111111B
;
IL12, IL10 to IL6 ← 0
Example 2: Reads interrupt latches
LD
WA, (ILL)
;
W ← ILH, A ← ILL
;
if IL7 = 1 then jump
Example 3: Tests an interrupt latch
TEST
(IL).7
JR
F, SSET
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88CU74-27
2
IL15 to 3 write data
Write
strobe
for IL
Internal reset
S
Q
IL15
R
INT5
External interrupts
control Register
EINTCR
S
Q
IL14
R
INTTC2
S
Q
IL12
R
S
Q
IL13
R
INT4ES
Edge selection, Digital
noise reject circuit
INT3ES
S
Q
IL11
R
INTSIO1
INT4
INT3
S
Q
IL10
R
INTTC4
S
Q
IL8
R
S
Q
IL7
R
S
Q
IL6
R
S
Q
IL5
R
S
Q
IL4
R
S
IL3 Q
R
S
Q
IL9
R
Edge selection, Digital
noise reject circuit
INT2ES
Edge selection,
Digital noise reject circuit
INT1NC, INT1ES
Edge selection,
Digital noise reject circuit
INT0EN
S
IL2 Q
R
EF15 to EF4
[DI]
instruction
Vector
table
address
Generator
&
Priority
Encoder
Instruction which clears IMF to “0”
Interrupt Enable Register
Interrupt Latches
INTSBI
INTTC3
INT2
INTTBT
INT1
INTTC1
INT0
INTSW
INTWDT
Interrupt acceptance
Release IDLE
mode request
Interrupt request
[EI] instruction
instruction which sets
IMF to “1”
[RETI] instruction only when
IMF was set before interrupt
was accepted.
Q
Interrupt Master Enable Flag
IMF
[RETI] instruction during
R S
maskble interrupt service
Maskable
interrupts
request
Non-maskable interrupts
Vector table address
TMP88CU74
Figure 1.5.1 Interrupt Controller Block Diagram
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TMP88CU74
(2) Interrupt enable register (EIR)
The interrupt enable register (EIR) enables and disables the acceptance of interrupts,
except for the pseudo non-maskable interrupts (software and watchdog timer interrupts).
Pseudo non-maskable interrupts are accepted regardless of the contents of the EIR;
however, the pseudo non-maskable interrupts cannot be nested more than once at the same
time. For example, the watchdog timer interrupt is not accepted during the software
interrupt service.
The EIR consists of an interrupt master enable flag (IMF) and the individual interrupt
enable flags (EF). This register is assigned to addresses 0003AH and 0003BH in the SFR,
and can be read and written by an instruction (including read-modify-write instructions
such as bit manipulation instructions).
1.
Interrupt master enable flag (IMF)
The interrupt master enable flag (IMF) enables and disables the acceptance of all
interrupts, except for pseudo non-maskable interrupts. Clearing this flag to “0”
disables the acceptance of all maskable interrupts. Setting to “1” enables the
acceptance of interrupts.
When an interrupt is accepted, this flag is cleared to “0” to temporarily disable the
acceptance of maskable interrupts. After execution of the interrupt service program,
this flag is set to “1” by the maskable interrupt return instruction [RETI] to again
enable the acceptance of interrupts. If an interrupt request has already been occurred,
interrupt service starts immediately after execution of the [RETI] instruction.
Pseudo non-maskable interrupts are returned by the [RETN] instruction. In this case,
the IMF is set to “1” only when pseudo non-maskable interrupt service is started with
interrupt acceptance enabled (IMF = 1). Note that the IMF remains “0” when cleared
by the interrupt service program.
The IMF is assigned to bit 0 at address 0003AH in the SFR, and can be read and
written by an instruction. The IMF is normally set and cleared by the [EI] and [DI]
instructions, and the IMF is initialized to “0” during reset.
2.
Individual interrupt enable flags (EF15 to EF4)
These flags enable and disable the acceptance of individual maskable interrupts,
except for an external interrupt 0. Setting the corresponding bit of an individual
interrupt enable flag to “1” enables acceptance of an interrupt, setting the bit to “0”
disables acceptance.
Example 1: Sets EF for individual interrupt enable, and sets IMF to “1”.
LDW
(EIRL), 1110100010100001B
; EF15 to EF13, EF11, EF7, EF5,
IMF ← 1
Example 2: Sets an individual interrupt enable flag to “1”.
SET
(EIRH).4
88CU74-28
;
EF12 ← 1
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TMP88CU74
IL
(0003C, 0003DH)
15
14
13
12
11
10
9
8
7
6
5
4
3
2
IL15
IL14
IL13
IL12
IL11
IL10
IL9
IL8
IL7
IL6
IL5
IL4
IL3
IL2
1
0
ILL (0003CH)
ILH (0003DH)
(Initial Value: 00000000 000000**)
EIR
EF15 EF14 EF13 EF12 EF11 EF10
EF9
EF8
EF7
EF6
EF5
EF4
IMF
(0003A, 0003BH)
EIRH (0003BH)
EIRL (0003AH)
(Initial Value: 00000000 0000***0)
Note 1:
Note 2:
Note 3:
Note 4:
Do not use any read-modify-write instruction such as bit manipulation for clearing IL.
Do not set IMF to “1” during non-maskable interrupt service program.
Bits1 and 0 in ILL are read in as undefined data when a read instruction is executed.
*: Don’ t care
Figure 1.5.2 Interrupt latch (IL) and interrupt enable register (EIR)
1.5.1
Interrupt Sequence
An interrupt request is held until the interrupt is accepted or the interrupt latch is
cleared to “0” by a reset or an instruction. Interrupt acceptance sequence requires 12
machine cycles (3.84 μs at fc = 12.5 MHz in the NORMAL mode) after the completion of the
current instruction execution. The interrupt service task terminates upon execution of an
interrupt return instruction [RETI] (for maskable interrupts) or [RETN] (for pseudo
non-maskable interrupts). Figure 1.5.3 shows the timing chart of interrupt acceptance
processing.
(1) Interrupt acceptance
Interrupt acceptance processing is as follows.
1.
The interrupt master enable flag (IMF) is cleared to “0” to temporarily disable the
acceptance of any following maskable interrupts. When a non-maskable interrupt
is accepted, the acceptance of any following interrupts is temporarily disabled.
2.
The interrupt latch (IL) for the interrupt source accepted is cleared to “0”.
3.
The contents of the program counter (return address) and the program status
word (PSW) are saved (pushed) on the stack in sequence of PSWH, PSWL, PCE,
PCH, PCL. The stack pointer (SP) is decremented five times.
4.
The entry address of the interrupt service program is read from the vector table,
and set to the program counter.
5.
The RBS control code is read from the vector table. The lower 4-bit of this code is
added to the RBS.
6.
The instruction stored at the entry address of the interrupt service program is
executed.
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Interrupt service task
1-machine cycle
INT5
INTTBT
IL15
IL6
IMF
Execution
Instruction
Address
bus
a+1
a
PC
a
Instruction
Interrupt acceptance
a+1
n−1 n−2 n−3 n−4
n
FFFE4 FFFE5 FFFE6 FFFE7
a
SP
b
n−1 n−2 n−3 n−4
n
RBS
b
b+1 b+2
b+1 b+2 b+3
n−5
k = i + (FFFE7). 3 − 0
i
(a) Interrupt acceptance
IMF
Execution
RETI instruction
Address
bus
PC
SP
RBS
c
c
c+1 n−4 n−3 n−2 n−1
c+1
n−5
n
c+2
n−4 n−3 n−2 n−1
k
a
a
a+1
a+1 a+2
n
i
(b) Return from interrupt instruction
Note 1: a: return address, b: entry address, c: address which the RETI instruction is stored
Note 2: The maximum response time from when an IL is set until an interrupt acceptance processing starts is 62/fc [s] or
62/fs [s] with interrupt enabled.
Figure 1.5.3 Timing Chart of Interrupt Acceptance and Interrupt Return Instruction
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Example: Correspondence between vector table address for INTTBT and the entry
address of the interrupt service program.
Vector table address
FFFE4H
43H
FFFE5H
D2H
FFFE6H
0CH
FFFE7H
06H
Entry address
CD243H
Vector
CD244H
CD245H
RBS
control
Interrupt
service
program
CD246H
A maskable interrupt is not accepted until the IMF is set to “1” even if the maskable
interrupt higher than the level of current servicing interrupt is occurred.
When nested interrupt service is necessary, the IMF is set to “1” in the interrupt
service program. In this case, acceptable interrupt sources are selectively enabled by
the individual interrupt enable flags. However, an acceptance of external interrupt 0
cannot be disabled by the EF; therefore, if disable is necessary, either the external
interrupt function of the INT0 pin must be disabled with the INT0EN in the external
interrupt control register (EINTCR) (the interrupt latch IL3 is not set at INT0EN = 0,
therefore, the rising edge of INT0 pin input can not be detected.) or an interrupt
processing must be avoided by the program.
Example 1: Disables an external interrupt 0 using the INT0EN
LD
(EINTCR), 00000000B
;
INT0EN ← 0
Example 2: Disables the processing of external interrupt 0 under the software control (using bit 0 at
address 000F0H as the interrupt processing disable switch)
PINT0:
TEST
(000F0H). 0
; Return without interrupt processing if
(000F0H) 0 = 1
SINT0:
JRS
T, SINT0
RETI
Interrupt processing
RETI
VINT0:
DL
PINT0
(2) Saving/Restoring general-purpose registers
During interrupt acceptance processing, the program counter (PC) and the program
status word (PSW) are automatically saved on the stack, but not the accumulator and
other registers. These registers are saved by the program if necessary. Also, when
nesting multiple interrupt services, it is necessary to avoid using the same data
memory area for saving registers.
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The following method is used to save/restore the general-purpose registers.
1.
General-purpose register save/restore by automatic register bank changeover
The general-purpose registers can be saved at high-speed by switching to a
register bank that is not in use. Normally, the bank 0 is used for the main task
and the banks 1 to 15 are assigned to interrupt service tasks. To increase the
efficiency of data memory utilization, the same bank is assigned for interrupt
sources which are not nested.
The switched bank is automatically restored by executing an interrupt return
instruction [RETI] or [RETN]. Therefore, it is not necessary for a program to save
the RBS.
Example: Register bank changeover
Interrupt processing
PINTxx:
RETI
VINTxx:
2.
DP
DB
PINTxx
1
;
RBS ← RBS + 1
General-purpose register save/restore by register bank changeover
The general-purpose registers can be saved at high-speed by switching to a
register bank that is not in use. Normally, the bank 0 is used for the main task
and the banks 1 to 15 are assigned to interrupt service tasks.
Example: Register bank changeover
PINTxx:
LD
RBS, n
Interrupt processing
RETI
VINTxx:
3.
DP
DB
PINTxx
0
;
Restores bank and Returns
;
Interrupt service routine entry address
General-purpose registers save/restore using push and pop instructions
To save only a specific register, and when the same interrupt source occurs
more than once, the general-purpose registers can be saved/restored using the
push/pop instructions.
Example: Register save/restore using push and pop instructions
PINTxx:
PUSH
WA
; Save WA register pair
Interrupt processing
POP
RETI
WA
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;
;
Restore WA register pair
Return
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Address (example)
SP
0023AH
A
SP
0023B
SP
W
0023C
PCL
PCL
PCL
PCH
PCH
PCH
0023E
PCE
PCE
PCE
0023F
0023D
PSWL
PSWL
PSWL
PSWH
PSWH
PSWH
At acceptance
of an interrupt
4.
At execution of a
push instruction
00240
SP
00241
At execution of an
interrupt return
instruction
At execution of a
pop instruction
General-purpose registers save/restore using data transfer instructions
Data transfer instruction can be used to save only a specific general-purpose
register during processing of single interrupt.
Example: Saving/restoring a register using data transfer instructions
PINTxx:
LD
(GSAVA), A
; Save A register
Interrupt processing
LD
RETI
A, (GSAVA)
Main task
Bank m
;
;
Restore A register
Return
Main task
Acceptance
of interrupt
Interrupt
service task
Switch to bank n by LD,
RBS and n instruction
Acceptance
of interrupt
Saving
registers
Bank m
Time
Bank m
Bank n
Interrupt return
Interrupt
service task
Switch to bank n
automatically
Restore to bank m
automatically by
[RETI]/[RETN]
Restoring
registers
Interrupt return
(a) Saving/restoring by register bank changeover
(b) Saving/restoring using push/pop or data transfer instructions
Figure 1.5.4 Saving/Restoring General-purpose Registers
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(3) Interrupt return
The interrupt return instructions [RETI]/[RETN] perform the following operations.
[RETI] Maskable interrupt return
[RETN] Non-maskable interrupt return
1. The contents of the program counter and the
program status word are restored from the
stack.
1. The contents of the program counter and
program status word are restored from the
stack.
2. The stack pointer is incremented 5 times.
2. The stack pointer is incremented 5 times.
3. The interrupt master enable flag is set to “1”.
3. The interrupt master enable flag is set to “1” only
when a non-maskable interrupt is accepted in
interrupt enable status. However, the interrupt
master enable flag remains at “0” when so clear
by an interrupt service program.
4. The interrupt nesting counter is decremented,
and the interrupt nesting flag is changed.
4. The interrupt nesting counter is decremented,
and the interrupt nesting flag is changed.
Interrupt requests are sampled during the final cycle of the instruction being
executed. Thus, the next interrupt can be accepted immediately after the interrupt
return instruction is executed.
Note:
1.5.2
When the interrupt processing time is longer than the interrupt request generation
time, the interrupt service task is performed but not the main task.
Software Interrupt (INTSW)
Executing the [SWI] instruction generates a software interrupt and immediately starts
interrupt processing (INTSW is highest prioritized interrupt). However, if processing of a
non-maskable interrupt is already underway, executing the SWI instruction will not
generate a software interrupt but will result in the same operation as the [NOP]
instruction.
Use the [SWI] instruction only for detection of the address error or for debugging.
Note:
1.
To use the SWI instruction for software break in the development tool, software interrupt
always generates even if the non-maskable interrupt is in progress.
Address error detection
FFH is read if for some cause such as noise the CPU attempts to fetch an instruction
from a non-existent memory address. Code FFH is the SWI instruction, so a software
interrupt is generated and an address error is detected. The address error detection
range can be further expanded by writing FFH to unused areas of the program memory.
Address-trap reset is generated in case that an instruction is fetched from RAM or SFR
areas.
2.
Debugging
Debugging efficiency can be increased by placing the SWI instruction at the software
break point setting address.
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1.5.3
External Interrupts
The TMP88CU74 has six external interrupt inputs ( INT0 , INT1, INT2, INT3, INT4,
INT5 ). Four of these are equipped with digital noise reject circuits(pulse inputs of less than
a certain time are eliminated as noise).
Edge selection is also possible with INT1 to INT4. The INT0 /P10 pin can be configured
as either an external interrupt input pin or an input/output port, and is configured as an
input port during reset.
Edge selection, noise reject control and INT0 /P10 pin function selection are performed by
the external interrupt control register (EINTCR).
Table 1.5.2 External Interrupts
Source
Pin
INT0
INT0
INT1
INT1
Secondary
Enable Conditions
Function Pin
P10
P11
IMF = 1, INT0EN = 1
Edge
Digital Noise Reject
Falling edge
⎯ (hysteresis input)
IMF･EF5 = 1
INT2
INT2
P16
IMF･EF7 = 1
INT3
INT3
P15/TC1
IMF･EF11 = 1
INT4
INT4
P17/TC3
IMF･EF12 = 1
INT5
INT5
P20/ STOP
IMF･EF15 = 1
Falling edge
or
Rising edge
Falling edge
Pulses of less than 15/fc or 63/fc [s]
are eliminated as noise. Pulses of
48/fc or 192/fc [s] or more are
considered to be signals.
Pulses of less than 7/fc [s] are
eliminated as noise. Pulses of 24/fc
[s] or more are considered to be
signals.
⎯ (hysteresis input)
Note 1: The noise reject function is turned off in SLOW and SLEEP modes. Also, the noise reject times are
not constant for pulses input while transiting between operating modes.
Note 2: The noise reject function is also affected for timer/counter input (TC1 pin, TC3 pin).
Note 3: The pulse width (both “H” and “L”evel) for input to the INT0 and INT5 pins must be over 2 machine
cycle.
INT0 / INT5 input
tINTL, tINTH ≥ 2 tcyc (Note: tcyc = 4/fm [s])
tINTL
tINTH
Note: tcyc = 4/fc [s] (in NORMAL1/2, IDEL1/2 mode)
4/fs (in SLOW, SLEEP mode)
Note 4: If a noiseless signal is input to the external interrupt pin in the NORMAL 1/2 or IDLE 1/2 mode, the
maximum time from the edge of input signal until the IL is set is as follows:
1. INT1 pin
49/fc [s] (INT1NC = 1),
193/fc [s] (INT1NC = 0)
2. INT2 pin
25/fc [s]
Note 5: Even if the falling edge of INT0 pin input is detected at INT0EN = 0, the interrupt latch IL3 is not set.
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EINTCR
7
6
(00037H)
INT1
NC
INT0
EN
5
4
3
2
1
INT4
ES
INT3
ES
INT2
ES
INT1
ES
0
(Initial value: 00*0 000*)
INT1NC
Noise reject time select
0: Pulses of less than 63/fc [s] are eliminated as noise
1: Pulses of less than 15/fc [s] are eliminated as noise
INT0EN
P10/ INT0 pin configuration
0: P10 input/output port
1: INT0 pin (Port P10 should be set to an input mode)
INT4ES
INT3ES
INT2ES
INT1ES
INT4 to INT1 edge select
R/W
0: Rising edge
1: Falling edge
Note 1: fc: High-frequency clock [Hz], *: Don’t care
Note 2: Edge detection during switching edge selection is invalid.
Note 3: Do not change EINTCR only when IMF = 0. After changing EINTCR, interrupt latches of external interrupt inputs
must be cleared to “0” using load instruction.
Note 4: In order to change of external interrupt input by rewriting the contents of INT2ES and INT3ES and INT4ES
during NORMAL 1/2 mode, clear interrupt latches of external interrupt inputs (INT2 and INT3 and INT4) after 8
machine cycles from the time of rewriting. During SLOW mode, 3 machine cycles are required.
Figure 1.5.5 External Interrupt Control Register
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1.6
Reset Circuit
The TMP88CU74 has four types of reset generation procedures: an external reset input, an
address trap reset output, a watchdog timer reset output and a system clock reset output. Table
1.6.1 shows on-chip hardware initialization by reset action.
The malfunction reset output circuit such as watchdog timer reset, address trap reset and
system clock reset is not initialized when power is turned on. The RESET pin can output level
“L” at the maximum 24/fc [s] (1.92 μs at 12.5 MHz) when power is turned on.
Table 1.6.1 Initializing Internal Status by Reset Action
On-chip Hardware
Initial Value
Program counter
(PC)
(FFFFEH to FFFFCH)
Stack pointer
(SP)
Not initialized
General-purpose registers
(W, A, B, C, D, E, H, L)
Register bank selector
0
(JF)
1
Zero flag
(ZF)
Not initialized
Carry flag
(CF)
Not initialized
Half carry flag
(HF)
Not initialized
Sign flag
(SF)
Not initialized
(VF)
Not initialized
Overflow flag
Interrupt master enable flag
(IMF)
0
Interrupt individinal enable flags (EF)
0
Interrupt latchs
0
1.6.1
(IL)
Initial Value
Prescaler and Divider of timing
generator
0
Watchdog timer
Enable
Output latches of I/O ports
Refer to I/O port
circuitry
Control registers
Refer to each of
control register
Not initialized
(RBS)
Jump status flag
On-chip Hardwear
External Reset Input
The RESET pin contains a Schmitt trigger (hysteresis) with an internal pull-up resistor.
When the RESET pin is held at “L” level for at least 3 machine cycles (12/fc [s]) with the
power supply voltage within the operating voltage range and oscillation stable, a reset is
applied and the internal state is initialized.
When the RESET pin input goes high, the reset operation is released and the program
execution starts at the vector address stored at addresses FFFFC to FFFFEH.
VDD
Reset input
RESET
Watchdog timer reset
Malfunction reset
output circuit
Sink open drain
Address trap reset
System clock reset
Figure 1.6.1 Reset Circuit
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1.6.2
Address-trap-reset
If the CPU should start looping for some cause such as noise and an attempt be made to
fetch an instruction from the on-chip RAM or the SFR area, an address-trap-reset will be
generated. Then, the RESET pin output will go low. The reset time is about 8/fc to 24/fc [s]
(0.64 to 1.92 μs at 12.5 MHz).
Instruction
execution
JP
RESET output
a
Reset release
Address-trap is occurred
(“L” output)
8/fc to 24/fc [s]
Instruction at address r
(H’)
4/fc to 12/fc [s]
20/fc [s]
Note 1: Address “a” is in the SFR or on-chip RAM space.
Note 2: During reset release, reset vector “r” is read out, and an instruction at address “r” is fetched and decoded.
Figure 1.6.2 Address-trap-reset
1.6.3
Watchdog Timer Reset
Refer to Section “2.4 Watchdog Timer”.
1.6.4
System-clock-reset
Clearing both XEN and XTEN (bits 7 and 6 in SYSCR2) to “0”, clearing XEN to “0” when
SYSCK = 0, or clearing XEN to “0” when SYSCK = 1 stops system clock, and causes the
microcomputer to deadlock. This can be prevented by automatically generating a reset
signal whenever XEN = XTEN = 0 is detected to continue the oscillation. Then, the RESET
pin output goes low from high-impedance. The reset time is about 8/fc to 24/fc [s] (0.64 to
1.92 μs at 12.5 MHz).
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2.
On-Chip Peripheral Functions
2.1
Special Function Registers (SFR)
The TMP88CU74 uses the memory mapped I/O system, and all peripheral control and data
transfers are performed through the special function registers (SFR).
The SFR are mapped to addresses 00000H to 0003FH, and DBR are mapped to address
00F80H to 00FFFH.
Figure 2.1.1 shows the TMP88CU74 SFR and DBR.
Address
00000H
01
02
03
04
05
06
07
08
09
0A
0B
0C
0D
0E
0F
10
11
12
13
14
15
16
17
18
19
1A
1B
1C
1D
1E
1F
Read
Write
P0 port
P1 port
P2 port
P3 port
P4 port
P5 port
P6 port
P7 port
P8 port
P9 port
−
P0CR (P0 port I/O output control)
−
P1CR (P1 port I/O output control)
−
P4CR (P4 port I/O output control)
−
P5CR (P5 port I/O output control)
ADCCR (AD converter control)
−
ADCDR (AD conv.result)
−
TREG1AL
−
TREG1AH
(Timer register 1A)
TREG1BL
(Timer register1B)
TREG1BH
−
TC1CR (TC1 control)
−
TC2CR (TC2 control)
−
TREG2L
−
TREG2H
(Timer register 2)
TREG3A (Timer register 3A)
−
TREG3B (Timer register 3B)
−
−
−
TC3CR (TC3 control)
TREG4 (Timer register 4)
TC4CR (TC4 control)
PD port
Reserved
Reserved
Address
00020H
21
22
23
24
25
26
27
28
29
2A
2B
2C
2D
2E
2F
30
31
32
33
34
35
36
37
38
39
3A
3B
3C
3D
3E
3F
Read
Write
−
SBICR1 (SBI control register)
SBIDBR (SBI Data buffer)
2
−
2
I CAR (I C Bus address)
SBISR (SBI status)
SBICR2 (SBI control register)
Reserved
Reserved
Reserved
SIO1SR (SIO status)
SIO1CR1 (SIO1 control 1)
SIO1CR2 (SIO1 control 2)
VFTSR (VFT status)
VFTCR1 (VFT control 1)
VFTCR2 (VFT control 2)
P3CR (Port I/O control)
Reserved
Reserved
Reserved
Reserved
DVCR
Reserved
Reserved
Reserved
−
WDTCR1
Watch-dog
−
WDTCR2
timer control
TBTCR (TBT/TG/DVO control)
EINTCR (External interrupt control)
SYSCR1
(system control)
SYSCR2
EIRL
(Interrupt enable register)
EIRH
ILL
(Interrupt latch)
ILH
PSWL
(program status word)
PSWH
(a) Special function registers
Note 1: Do not access reserved areas by the program.
Note 2: −: Cannot be accessed.
Note 3: Write-only registers and interrupt latches cannot use the read-modify-write instructions (bit manipulation
instructions such as SET, CLR, etc. and logical operation instructions such as AND, OR, etc.).
Note 4: When defining address 0003FH with assembler symbols, use GRBS.
Address 0003EH must be GPSW/GFLAG.
Figure 2.1.1 SFR and DBR (1/2)
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Address
Read
Write
00F80H
Note:
Do not access reserved areas by the program.
VFT
display data buffer
(80 bytes)
00FCF
00FD0
Reserved
00FF7
00FF8
F9
FA
FB
FC
FD
FE
FF
SIO
transmit data buffer
(8 bytes)
(b) Data Buffer Registers
Figure 2.1.2 SFR and DBR (2/2)
2.2
I/O Ports
The TMP88CU74 each have 11 parallel input/output ports (71 pins) each as follows:
1. Port P0
8-bit I/O port
Serial port input/output
2.
Port P1
8-bit I/O port
External interrupt input, timer/counter input,
and divider output
3.
Port P2
3-bit I/O port
Low-frequency resonator connections, external interrupt
input, and STOP mode release signal input
4.
Port P3
3-bit I/O port
Serial bus interface input/output
5.
Port P4
8-bit I/O port
Anarog input
6.
Port P5
4-bit I/O port
Anarog input
7.
Port P6
8-bit I/O port
VFT output
8.
Port P7
8-bit I/O port
VFT output
9.
Port P8
8-bit I/O port
VFT output
10. Port P9
8-bit I/O port
VFT output
11. Port PD
5-bit I/O port
VFT output
Each output port contains a latch, which holds the output data. Input ports excluding do not
have latches, so the external input data should either be held externally until read or reading
should be performed several times before processing. Figure 2.2.1 shows input/output timing
examples.
External data is read from an I/O port in the S1 state of the read cycle during execution of the
read instruction. This timing can not be recognized from outside, so that transient input such as
chattering must be processed by the program.
Output data changes in the S2 state of the write cycle during execution of the instruction
which writes to an I/O port.
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Fetch cycle
Instruction
execution
cycle
Fetch cycle
Read cycle
S0 S1 S2 S3 S0 S1 S2 S3 S0 S1 S2 S3
Ex.: LD A, (x)
Input strobe
Data input
(a) Input timing
Fetch cycle
Instruction
execution
cycle
Fetch cycle
Write cycle
S0 S1 S2 S3 S0 S1 S2 S3 S0 S1 S2 S3
Ex.: LD (x) , A
Output latch
pulse
Data output
Old
New
(b) Output timing
Note: The positions of the read and write cycles may vary, depending on the instruction.
Figure 2.2.1 Input/Output Timing (Example)
When reading an I/O port except programmable I/O ports P0 and P1, whether the pin input
data or the output latch contents are read depends on the instructions, as shown below:
(a) Instructions that read the output latch contents
1.
XCH r, (src)
2.
CLR/SET/CPL (src).b
3.
CLR/SET/CPL (pp).g
4.
LD (src).b, CF
5.
LD (pp).b, CF
6.
XCH CF, (src), b
7.
ADD/ADDC/SUB/SUBB/AND/OR/XOR (src), n
8.
(src) side of ADD/ADDC/SUB/SUBB/AND/OR/XOR (src), (HL)
9.
MXOR (src), m
(b) Instructions that read the pin input data
1.
(HL) side of ADD/ADDC/SUB/SUBB/AND/OR/XOR (src), (HL)
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2.2.1
Port P0 (P07 to P00)
Port P0 is an 8-bit general-purpose input/output port which can be configured as either
an input or an output in one-bit unit under software control. Input/output mode is specified
by the corresponding bit in the port P0 input/output control register (P0CR). Port P0 is
configured as an input if its corresponding P0CR bit is cleared to “0”, and as an output if its
corresponding P0CR bit is set to “1”.
Port P0 is also used as Serial interfase input/output.
When used as a function pins should be set to the input mode. The pin should be set to
the output mode and beforehand the output latch should be set to “1”.
Note:
Input mode port reads the state of input pin. When input/output mode is used to mixed,
the contents of output latch setting to the input mode may be overwritten by executing bit
manipulation instructions.
P0CRi
Data input
Data output
D Q
P00, P01
Output latch
Control output
Control input
P0CRi
Data input
Data output
D Q
P02 to P07
Output latch
Control output
Control input
7
P0
(00000H)
P0CR
(0000AH)
6
5
4
3
P07
P06
P05
P04
P03
7
6
5
4
3
2
1
0
P02
P01
P00
SO1
SI1 SCK1
2
1
(Initial value: 0000 0000)
0
(Initial value: 0000 0000)
P0CR
I/O control for port P0
(Setting per bit)
0: Input mode
1: Output mode
Write
only
Figure 2.2.2 Port P0 and P0CR
Example: Setting the upper 4 bits of port P0 as an input port and the lower 4 bits as an output port (Initial
output data are 1010B).
LD
(P0), 00001010B
; Sets initial data to P0 output latches
LD
(P0CR), 00001111B
; Sets the port P0 input/output mode
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2.2.2
Port P1 (P17 to P10)
Port P1 is an 8-bit input/output port which can be configured as an input or an output in
one-bit unit under software control. Input/output mode is specified by the corresponding bit
in the port P1 input/output control register (P1CR). Port P1 is configured as an input if its
corresponding P1CR bit is cleared to “0”, and as an output if its corresponding P1CR bit is
set to “1”. During reset, P1CR is initialized to “0”, which configures port P1 as an input .
The P1 output latches are also initialized to “0”.
Data is written into the output latch regardless of P1CR contents. Therefore initial
output data should be written into the output latch before setting P1CR. Port P1 is also
used as an external interrupt input, a timer/counter input, and a divider output. When
used as a secondary function pin, the input pins should be set to the input mode, and the
output pins should be set to the output mode and beforehand the output latch should be set
to “1”.
It is recommended that pins P11 and P15 and P16 and P17 should be used as external
interrupt inputs, timer/counter input, or input ports. The interrupt latch is set on the rising
or falling edge of the output when used as output ports.
Pin P10 ( INT0 ) can be configured as either an I/O port or an external interrupt input
with INT0EN (bit 6 in EINTCR). During reset, the pin P10 ( INT0 ) is configured as an input
port P10.
P1CRi
Data input
Data output
D Q
P1i
Output latch
Control output
Control input
Note: i = 7 to 0
P1
(00001H)
P1CR
(0000BH)
7
P17
2
P12
1
P11
INT4 INT2 INT3 PWM DVO
PPG
INT1 INT0
TC3
TC2
7
6
P16
6
5
P15
4
P14
TC1
PD0
5
4
3
P13
3
2
1
0
P10
(Initial value: 0000 0000)
0
(Initial value: 0000 0000)
P1CR
I/O control for port P1
(Setting per bit)
0: Input mode
1: Output mode
Write
only
Figure 2.2.3 Port P1 and P1CR
Example: Sets P17, P16 and P14 as output ports, P13 and P11 as input ports, and the others as function
pins. Internal output data is “1” for the P17 and P14 pins, and “0” for the P16 pin.
LD
(EINTCR), 01000000B
; INT0EN ← 1
LD
(P1), 10111111B
; P17 ← 1, P14 ← 1, P16 ← 0
LD
(P1CR), 11010000B
Note: Input mode port reads the state of input pin. When input/output mode is used to mixed,
the contents of output latch setting to the input mode may be overwritten by executing
bit manipulation instructions.
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2.2.3
Port P2 (P22 to P20)
Port P2 is a 3-bit input/output port. It is also used as an external interrupt input, and
low-frequency crystal connection pins When used as an input port, or the secondary
function pin, the output latch should be set to “1”. During reset, the output latches are
initialized to “1”.
A low-frequency crystal (32.768 kHz) is connected to pins P21 (XTIN) and P22 (XTOUT)
in the dual-clock mode. In the single-clock mode, pins P21 and P22 can be used as normal
input/output ports.
It is recommended that the P20 pin should be used as an external interrupt input, a
STOP mode release signal input, or an input port. If used as an output port, the interrupt
latch is set on the falling edge of the output pulse.
When a read instruction for port P2 is executed, bits 7 to 3 in P2 read in as undefined
data.
SET/CLR/CPL/others
CMP/MCMP/TEST/others
Data input
Output latch
Data output
Control input
Data input
P20 ( INT5 / STOP )
D Q
Osc. enable
Data output
D Q
P21 (XTIN)
D Q
P22 (XTOUT)
Data input
Data output
Note 1: *: Don’t care
Note 2: XTEN is bit 6 in SYSCR2
XTEN
fs
7
6
5
4
3
P2
(00002H)
2
1
0
P22
XTOUT
P21
XTIN
P20
INT5
STOP
(Initial value: **** *111)
Figure 2.2.4 Port P2
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2.2.4
Port P3 (P32 to P30)
Port P3 is an 3-bit input/output port and serial interface (SIO1) input/output.
Input/output mode is specified by the port P3 input/output control register (P3CR).
During reset P3CR is initialized to “0” and Port P3 is input mode. The port P3 output
latches are initialized to “0”.
P3 is serial bus interface input/output.
When used as function pins set to output mode by Port P3 I/O control register, and I/O is
controlling by output data.
The output buffer can be change to the tri-state or shink-open drain by Port P3 I/O
control register (P3CR).
When a read instruction for port P3 is executed, bits 7 to 3 in P3 read is an undefined
data.
Note:
Input mode port reads the state of input pin. When input/output mode is used to mixed,
the contents of output latch setting to the input mode may be overwritten by executing bit
manipulation instructions.
P3CRi
Data input
Data output
D Q
P3i
Output latch
Note 1: *: Don’t care
Note 2: i = 2 to 0
Output control
P3ODRi
Input control
7
6
5
4
3
P3
(00003H)
P3CR
(0002BH)
7
P3CR
6
5
4
3
P3O
DR2
P3O
DR1
P3O
DR0
2
1
0
P32
SCL
SI0
P31
SDA
SO0
P30
SCK 0
2
1
0
P3CR
(Initial value: **** *000)
(Initial value: **00 0000)
0: Input mode
1: Output mode
I/O control of port P3
(Setting per bit)
P3ODR0
P30 tri-state/open-drain control
P3ODR1
P31 tri-state/open-drain control
P3ODR2
P32 tri-state/open-drain control
0: Tri-state
1: Open-drain
Write
only
Figure 2.2.5 P3 and Port P3 I/O Control Register
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2.2.5
Port P4 (P47 to P40)
Ports P4 is an 8-bit input/output port which can be configured as an input or an output in
one-bit unit under software control. Input/output mode is specified by the corresponding bit
in the port P4 input/output control register (P4CR).
At reset, P4CR is set to 0 and AINDS is cleared to 0. Thus, P4 becomes an analog input
port. At the same time, the output latch of port P4 is initialized to 0. P4CR is a write-only
register. Pins not used for analog input can be used as I/O ports. But do not execute the
output instruction to keep the accuracy in AD conversion. Executing an input instruction
on port P4 when the AD converter is in use reads 0 at pins set for analog input: 1 or 0 at
pins not set for analog input, depending on the pin input level.
Analog input
AINDS
SAIN
P4CRi
read
Data input
Data output
P4
(00004H)
P4CR
(0000CH)
D Q
P4i
7
6
5
4
3
2
1
0
P47
P46
P45
P44
P43
P42
P41
P40
AIN7 AIN6 AIN5 AIN4 AIN3 AIN2 AIN1 AIN0
7
6
5
4
3
2
1
(Initial value: 0000 0000)
0
(Initial value: 0000 0000)
P4CR
Port P4 I/O control
(Setting per bit)
0: Input mode
1: Output mode
Write
only
Note 1: Set the terminal which is used as an analog input to input mode.
Note 2: i = 0 to 7
Figure 2.2.6 P4 and Port P4 Control Register
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2.2.6
Port P5 (P53 to P50)
Ports P5 is an 8-bit input/output port which can be configured as an input or an output in
one-bit unit under software control. Input/Output mode is specified by the corresponding
bit in the port P5 input/output control register (P5CR).
At reset, P5CR is set to 0 and AINDS is cleared to 0. Thus, P5 becomes an analog input
port . At the same time, the output latch of port P5 is initialized to 0. P5CR is a write-only
register. Pins not used for analog input can be used as I/O ports. But do not execute the
output instruction to keep the accuracy in AD conversion. Executing an input instruction
on port P5 when the AD converter is in use reads 0 at pins set for analog input: 1 or 0 at
pins not set for analog input, depending on the pin input level.
Analog input
AINDS
SAIN
P5CRi
read
Data input
Data output
7
6
D Q
5
4
P5
(00005H)
P5CR
(0000DH)
P5i
3
2
1
0
P53
P52
P51
P50
AIN8
AIN6
1
0
AIN11 AIN10
7
6
5
4
3
2
(Initial value: **** 0000)
(Initial value: **** 0000)
P5CR
Port P5 I/O control
(Setting per bit)
0: Input mode
1: Output mode
Write
only
Note 1: Set the terminal which is used as an analog input to input mode.
Note 2: i = 0 to 3
Note 3: *: Don’t care
Figure 2.2.7 P5 and Port P5 I/O Control Register
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2.2.7
Port 6 (P67 to P60)
Port 6 is an 8-bit high-breakdown voltage input/output port, and also used as a VFT
driver output, which can directly drive vacuum fluorescent tube (VFT).
When used as an VFT driver output, the output latch should be cleared to “0”.
Pins not used for VFT driver output can be used as I/O ports.
When use an VFT driver and normal input/output at the same time, VFT driver output
data buffer memory (DBF) need to cleared to “0”.
The output latches are initialized to “0” during reset.
It recommends that port 6 shoud be used to drive directly drive vacuum fluorescent tube
(VFT), since this port has a pull down resistance.
CMP/MCMP/TEST/Others
Data input
SET/CLR/
CPL/Others
Data output
D Q
P6i
Output latch
P6
(00006H)
Note: i = 7 to 0
VKK
2
1
7
6
5
4
3
P67
P66
P65
P64
P63
P62
P61
P60
0
V7
V6
V5
V4
V3
V2
V1
V0
(Initial value: 0000 0000)
Figure 2.2.8 Port P6
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2.2.8
Port 7 (P77 to P70)
Port 7 is an 8-bit high-breakdown voltage input/output port, and also used as a VFT
driver output, which can directly drive vacuum fluorescent tube (VFT).
When used as an VFT driver output, the output latch should be cleared to “0”.
Pins not used for VFT driver output can be used as I/O ports.
When use an VFT driver and normal input/output at the same time, VFT driver output
data buffer memory (DBF) need to cleared to “0”.
The output latches are initialized to “0” during reset.
It recommends that port 7 shoud be used to drive directly drive vacuum fluorescent tube
(VFT), since this port has a pull down resistance.
CMP/MCMP/TEST/Others
Data input
SET/CLR/
CPL/Others
Data output
D Q
P7i
Output latch
Note: i = 7 to 0
VFT driver output
VKK
P7
(00007H)
7
6
5
4
3
2
1
0
P77
P76
P75
P74
P73
P72
P71
P70
V15
V14
V13
V12
V11
V10
V9
V8
(Initial value: 0000 0000)
Figure 2.2.9 Port P7
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2.2.9
Port 8 (P87 to P80)
Port 8 is an 8-bit high-breakdown voltage input/output port, and also used as a VFT
driver output, which can directly drive vacuum fluorescent tube (VFT).
When used as an VFT driver output, the output latch should be cleared to “0”.
Pins not used for VFT driver output can be used as I/O ports.
When use an VFT driver and normal input/output at the same time, VFT driver output
data buffer memory (DBF) need to cleared to “0”.
The output latches are initialized to “0” during reset.
It recommends that port 8 shoud be used to drive directly drive vacuum fluorescent tube
(VFT), since this port has a pull down resistance.
CMP/MCMP/TEST/Others
Data input
SET/CLR/
CPL/Others
Data output
D Q
P8i
Output latch
Note: i = 7 to 0
VFT driver output
P8
(00008H)
VKK
2
1
7
6
5
4
3
P87
P86
P85
P84
P83
P82
P81
P80
0
V23
V22
V21
V20
V19
V18
V17
V16
(Initial value: 0000 0000)
Figure 2.2.10 Port P8
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2.2.10
Port 9 (P97 to P90)
Port 9 is an 8-bit high-breakdown voltage input/output port, and also used as a VFT
driver output, which can directly drive vacuum fluorescent tube (VFT).
When used as an VFT driver output, the output latch should be cleared to “0”.
Pins not used for VFT driver output can be used as I/O ports.
When use an VFT driver and normal input/output at the same time, VFT driver output
data buffer memory (DBF) need to cleared to “0”.
The output latches are initialized to “0” during reset.
It recommends that port 9 shoud be used to drive directly drive vacuum fluorescent tube
(VFT), since this port has a pull down resistance.
CMP/MCMP/TEST/Others
Data input
SET/CLR/CPL/Others
Data output
D Q
P9i
Output latch
VFT driver output
Note: i = 7 to 0
P9
(00009H)
VKK
2
1
7
6
5
4
3
P97
P96
P95
P94
P93
P92
P91
P90
0
V31
V30
V29
V28
V27
V26
V25
V24
(Initial value: 0000 0000)
Figure 2.2.11 Port P9
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2.2.11
PD (PD4 to PD0)
Port PD is high-breakdown voltage input/output port, and also used as a VFT driver
output, which can directly drive vacuum fluorescent tube (VFT).
General-purpose or segment can be selected for each bit by VSEL (bit 4 to 0) in VFT
driver control register 1 (VFTCR1). The VSEL is cleared to “0” during reset, which used as
an input mode. When used as an input port or VFT driver output, the output latch set to “0”.
The output latches are initialized to “0” during reset.
When a read instruction for port PD is executed bit 7 to 5 in PD read in as undefined
data.
CMP/MCMP/TEST/Others
Data input
SET/CLR/
CPL/Others
Data output
D Q
Output latch
PDi
VFT driver output control
VFT driver output
Note: i = 4 to 0
*: Don’t care
VKK
7
PD
(0001DH)
6
5
4
3
2
1
0
PD4
PD3
PD2
PD1
PD0
V36
V35
V34
V33
V32
(Initial value: ***0 0000)
Figure 2.2.12 PD Port
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2.3
Time Base Timer (TBT)
The time base timer generates time base for key scanning, dynamic displaying, etc. It also
provides a time base timer interrupt (INTTBT).
An INTTBT is generated on the first rising edge of source clock (the divider output of the
timing generator) after the time base timer has been enabled. The divider is not cleared by the
program; therefore, only the first interrupt may be generated ahead of the set interrupt period
(Figure 2.3.1 (b)).
The interrupt frequency (TBTCK) must be selected with the time base timer disabled (the
interrupt frequency must not be changed with the disable from the enable state). Both
frequency selection and enabling can be performed simultaneously.
fc/223, fc/224
fc/221, fc/222
fc/216, fc/217
fc/214, fc/215
fc/213, fc/214
fc/212, fc/213
fc/211, fc/212
fc/29, fc/210
or
or
or
or
or
or
or
or
fs/215
fs/213
fs/28
fs/26
fs/25
fs/24
fs/23
fs/2
MPX
A
B
C
Source
D
clock
Y
E
F
G
H S
3
TBTCK
Rising edge
detector
INTTBT interrupt request
TBTEN
TBTCR
Time base timer control register
(a) Configuration
Source clock
TBTEN
INTTBT
Interrupt period
Enable TBT
(b) Time base timer interrupt
Figure 2.3.1 Time Base Timer
Example: Sets the time base timer frequency to fc/216 [Hz] and enables an INTTBT interrupt.
LD
(TBTCR), 00001010B
SET
(EIRL). 6
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7
TBTCR
(00036H)
(DVOEN)
TBTEN
6
5
(DVOCK)
4
3
2
(DV7CK) TBTEN
1
TBTCK
0
(Initial value: 0**0 0***)
0: Disable
Time base timer
enable/disable
1: Enable
NORMAL1/2, IDLE1/2 mode
DV7CK = 0
DV7CK = 1
DV1CK = 0 DV1CK = 1 DV1CK = 0 DV1CK = 1
TBTCK
Time base timer interrupt
frequency select [Hz]
000
001
010
011
100
101
110
111
SLOW,
SLEEP
mode
fc/223
fc/221
fc/216
fc/214
fc/213
fc/212
fc/211
fc/224
fc/222
fc/217
fc/215
fc/214
fc/213
fc/212
fs/215
fs/213
fs/28
fs/26
fs/25
fs/24
fs/23
fs/215
fs/213
fs/28
fs/26
fs/25
fs/24
fs/23
fs/215
fs/213
−
−
−
−
−
fc/29
fc/210
fs/2
fs/2
−
R/W
Note: fc: High-frequency clock [Hz], fs: Low-frequency clock [Hz], *: Don’t care
Figure 2.3.2 Time Base Timer Control Register
Table 2.3.1 Time Base Timer Interrupt Frequency (Example: fc = 12.5 MHz, fs = 32.8 kHz)
Time Base Timer Interrupt Frequency [Hz]
NORMAL1/2, IDLE1/2 Mode
TBTCK
DV7CK = 0
DV1CK = 0
000
001
010
011
100
101
110
111
1.49
5.96
190.73
762.94
1525.88
3051.76
6103.52
24414.06
DV1CK = 1
0.75
2.98
95.37
381.47
762.94
1525.88
3051.76
12207.03
DV7CK = 1
DV1CK = 0
1
4
128
512
1024
2048
4096
16384
88CU74-54
DV1CK = 1
1
4
128
512
1024
2048
4096
16384
SLOW,
SLEEP Mode
1
4
⎯
⎯
⎯
⎯
⎯
⎯
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2.4
Watchdog Timer (WDT)
The watchdog timer is a fail-safe system to rapidly detect the CPU malfunctions such as
endless looping caused by noise or the like, or deadlock and resume the CPU to the normal
state.
The watchdog timer signal for detecting malfunction can be selected either a reset output or a
pseudo non-maskable interrupt request. However, selection is possible only once after reset. At
first the reset output is selected.
When the watchdog timer is not being used for malfunction detection, it can be used as a
timer to generate an interrupt at fixed intervals.
2.4.1
Watchdog Timer Configuration
Reset release
Selector
fc/223, fc/224 or fs/215
fc/221, fc/222 or fs/213
fc/219, fc/220 or fs/211
fc/217, fc/218 or fs/29
Binary
Counters
R
Clock
Clear
Overflow
1
Reset output
WDT output
S
2
Q
RESET
Interrupt request
2
INTWDT
Internal reset
Q
S
WDTT
R
WDTEN
Writing
disable code
Writing
clear code
WDTOUT
Controller
00034H
WDTCR1
00035H
WDTCR2
Watchdog timer control registers
Figure 2.4.1 Watchdog Timer Configuration
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2.4.2
Watchdog Timer Control
Figure 2.4.2 shows the watchdog timer control registers (WDTCR1, WDTCR2). The
watchdog timer is automatically enabled after reset.
(1) Malfunction detection methods using the watchdog timer
The CPU malfunction is detected at follows.
1.
Setting the detection time, selecting output, and clearing the binary counter.
2.
Repeatedly clearing the binary counter within the setting detection time
If the CPU malfunctions such as endless looping or deadlock occur for any cause, the
watchdog timer output will become active at the rising of an overflow from the binary
counters unless the binary counters are cleared. At this time, when WDTOUT = 1 a
reset is generated, which drives the RESET pin low to reset the internal hardware and
the external circuit. When WDTOUT = 0, a watchdog timer interrupt(INTWDT) is
generated.
The watchdog timer temporarily stops counting in STOP mode including warm-up or
IDLE mode, and automatically restarts (continues counting) when the STOP/IDLE
mode is released.
Note:
Just right before disabling the watchdog timer, disable the acceptance of interrupts
(DI) and clear the watchdog timer.
If the watchdog timer is disabled under conditions other than the above, the proper
operation cannnot be guaranteed.
Example:
DI
LD
LDW
EI
(WDTCR2), 4EH
(WDTCR1), B100H
;
;
;
;
Disable interrupt acceptance.
Clears the watchdog timer.
Disables the watchdog timer.
Enables interrupt acceptance.
Example: Sets the watchdog timer detection time to 221/fc [s] and resets the CPU malfunction.
LD
(WDTCR2), 4EH
; Clears the binary counters
LD
(WDTCR1), 00001101B
; WDTT ← 10, WDTOUT ← 1
LD
(WDTCR2), 4EH
; Clears the binary counters (always clear
Within WDT
immediately after changing WDTT)
detection
time
LD
(WDTCR2), 4EH
; Clears the binary counters
Within WDT
detection
time
LD
(WDTCR2), 4EH
; Clears the binary counters
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Watchdog Timer Register 1
7
6
WDTCR1
(00034H)
5
4
3
1
0
WDT
OUT
WDTT
(Initial value: **** 1001)
0: Disable
(It is necessary to write the disable code to WDTCR2)
1: Enable
Watchdog timer
enable/disable
WDTEN
2
WDT
EN
NORMA1/2 mode
DV7CK = 0
WDTT
Watchdog timer
detection time [s]
WDTOUT
Watchdog timer
output select
DV7CK = 1
DV1CK = 0 DV1CK = 1 DV1CK = 0 DV1CK = 1
225/fc
223/fc
221/fc
219/fc
00
01
10
11
226/fc
224/fc
222/fc
220/fc
217/fs
215/fs
213/fs
211/fs
217/fs
215/fs
213/fs
211/fs
SLOW
mode
217/fs
215/fs
213/fs
211/fs
Write
only
0: Interrupt request
1: Reset output
Note 1: WDTOUT cannot be set to “1” by program after clearing WDTOUT to “0”.
Note 2: fc: High-frequency clock [Hz], fs: Low-frequency clock [Hz], *: Don’t care
Note 3: WDTCR1 is a write-only register and must not be used with any of read-modify-write instructions.
Note 4: Disable the watchdog timer or clear the counter just before switching to STOP mode.
When the counter is cleared just before switching to STOP mode, clear the counter again subsequently to
releasing STOP mode.
Watchdog Timer Register 2
7
6
WDTCR2
5
4
3
2
1
0
(Initial value: **** ****)
(00035H)
4EH:
Watchdog timer binary counter clear
(clear code)
Watchdog timer control code
B1H: Watchdog timer disable
WDTCR2
write register
(disable code)
others: Invalid
Write
only
Note 1: The disable code is invalid unless written when WDTEN = 0.
Note 2: *: Don’t care
Note 3: The binary counter of the watchdog timer must not be cleared by the interrupt task.
Figure 2.4.2 Watchdog Timer Control Registers
(2) Watchdog timer enable
The watchdog timer is enabled by setting WDTEN (bit 3 in WDTCR1) to “1”.
WDTEN is initialized to “1” during reset, so the watchdog timer operates immediately
after reset is released.
Example :
Enables watchdog timer
(3) Watchdog timer disable
The watchdog timer is disabled by writing the disable code (B1H) to WDTCR2 after
clearing WDTEN (bit 3 in WDTCR1) to “0”. The watchdog timer is not disabled if this
procedure is reversed and the disable code is written to WDTCR2 before WDTEN is
cleared to “0”. During disabling the watchdog timer, the binary counters are cleared to
“0”.
Example: Disables watchdog timer
LDW
(WDTCR1), 0B101H
88CU74-57
;
WDTEN ← 0, WDTCR2 ←
Disable code
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TMP88CU74
Table 2.4.1 Watchdog Timer Detection Time (Example: fc = 12.5 MHz, fs = 32.8 kHz)
Watchdog Timer Detection Time [s]
NORMAL1/2 Mode
WDTT
DV7CK = 0
00
01
10
11
2.4.3
DV7CK = 1
DV1CK = 0
DV1CK = 1
2.684
671.089
167.772
41.943
5.369
1.342
335.544
83.886
s
ms
ms
ms
SLOW Mode
DV1CK = 0
DV1CK = 1
4
1
250
62.5
4
1
250
62.5
s
s
ms
ms
s
s
ms
ms
4
1
250
62.5
s
s
ms
ms
s
s
ms
ms
Watchdog Timer Interrupt (INTWDT)
This is a pseudo non-maskable interrupt which can be accepted regardless of the
contents of the EIR. If a watchdog timer interrupt or a software interrupt is already
accepted, however, the new watchdog timer interrupt waits until the previous interrupt
processing is completed (the end of the [RETN] instruction execution).
The stack pointer (SP) should be initialized before using the watchdog timer output as an
interrupt source with WDTOUT.
Example: Watchdog timer interrupt setting up
LD
SP, 0023FH
LD
2.4.4
(WDTCR1), 00001000B
;
Sets the stack pointer
;
WDTOUT ← 0
Watchdog Timer Reset
If the watchdog timer output becomes active, a reset is generated, which drives the
RESET pin (sink open drain input/output with pull-up) low to reset the internal hardware
and external circuits. The reset output time is about 8/fc to 24/fc [s] (0.64 to 1.92 μs at fc =
12.5 MHz, fcgck = fc).
Note:
The high-frequency clock oscillator also turns on when a watchdog timer reset is
generated in SLOW mode. The reset output time is 8/fc to 24/fc [s]. Therefore, the reset
time may include a certain amount of error if there is any fluctuation of the oscillation
frequency at starting the high-frequency clock oscillation. Thus, the reset time must be
considered an approximated value.
219/fc [s]
17
2 /fc
Clock
Binary counter
(WDTT = 11B)
1
2
3
0
1
2
3
0
Overflow
INTWDT interrupt
WDT reset output
(High-Z)
(“L” output)
Writes 4EH to WDTCR2
Figure 2.4.3 Watchdog Timer Interrupt/Reset
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TMP88CU74
2.5
Divider Output ( DVO )
Approximately 50% duty pulse can be output using the divider output circuit, which is useful
for piezoelectric buzzer drive. Divider output is from pin P13 ( DVO ). The P13 output latch
should be set to “1” and then the P13 should be configured as an output mode.
TBTCR
(00036H)
7
6
DVOEN
5
DVOCK
DVOEN
4
3
2
1
(DV7CK) (TBTEN)
0
(Initial value: 0**0 0***)
(TBTCK)
0: Disable
1: Enable
Divider output enable/disable
NORMAL1/2, IDLE1/2 mode
DV7CK = 0
DVOCK
DV7CK = 1
DV1CK = 0 DV1CK = 1 DV1CK = 0 DV1CK = 1
Divider output ( DVO )
00
01
10
11
frequency selection [Hz]
fc/213
fc/212
fc/211
fc/210
fc/214
fc/213
fc/212
fc/211
fs/25
fs/24
fs/23
fs/22
SLOW,
SLEEP
mode
fs/25
fs/24
fs/23
fs/22
R/W
fs/25
fs/24
fs/23
fs/22
Note: fc: High-frequency clock [Hz], fs: Low-frequency clock [Hz], *: Don’t care
Figure 2.5.1 Divider Output Control Register
Example: 1.5 kHz pulse output (at fc = 12.5 MHz, DV1CK = 0)
SET
(P1).3
; P13 output latch ← 1
LD
(P1CR), 00001000B
; Configures P13 as an output mode
LD
(TBTCR), 10000000B
; DVOEN ← 1, DVOCK ← 00
Table 2.5.1 Divider Output Frequency (Example: at fc = 12.5 MHz, fs = 32.8 kHz)
Divider Output Frequency [kHz]
NORMAL1/2, IDLE1/2 MODE
DVOCK
DV7CK = 0
00
01
10
11
DV1CK = 0
DV1CK = 1
DV1CK = 0
DV1CK = 1
1.526 k
3.502
6.104
12.207
0.763 k
1.526
3.502
6.104
1.024 k
2.048
4.096
8.192
1.024 k
2.048
4.096
8.192
Output latch
Data output
DV7CK = 1
SLOW, SLEEP
Mode
1.024 k
2.048
4.096
8.192
Output enable (P1CR3)
D Q
P13 ( DVO )
Selector
fc/213, fc/214 or fs/25
fc/212 ,fc/213 or fs/24
fc/211 ,fc/212 or fs/23
fc/210 ,fc/211 or fs/22
A
B
C
D
Y
P13 output latch
S
2
DVOCK
DVOEN
DVOEN
DVOCK
DVO pin output
Divider output control register
(a) Configuration of divider output circuit
(b) Divider output timing chart
Figure 2.5.2 Divider Output
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B
A
S A Y
TC1 pin
fc/211, fc/212 or fs/23
fc/27 or fc/28
fc/23 or fc/24
INT2ES
88CU74-60
2
Y
A Source
S clock
B
MPX
SCAP1
Capture
Window mode
TC1 control register
TC1CR
D
A
BY
CS
MPX
Clear
Y
A
CMP
S
Set
Clear
Enable
Toggle
Q
Pulse width
measurement
mode
TREG1AH TREG1AL
TREG1BH TREG1BL
Write strobe
Match detection control
Match
TC1S clear
TREG1A
PPG output
mode
16-bit timer register 1A, B
TREG1B
B
MPX
16-bit up-counter
Clear
MPPG1
INTTC1 interrupt
TC1CR write
strobe
PPG
output
mode
Internal
reset
TFF1
Clear
Set
Q
Toggle
pin
PPG
Configuration
TC1CK
B
Start
Set Q
Command start
METT1
External External
trigger trigger start
Decoder
TC1S
2
Rising
Edge detector
Pulse width
measurement
mode
Falling
MPX
Y
2.6.1
S
2.6
MCAP1
TMP88CU74
16-Bit Timer/Counter 1 (TC1)
Figure 2.6.1 Timer/Counter 1 (TC1)
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TMP88CU74
2.6.2 Control
The timer/counter 1 is controlled by a timer/counter 1 control register (TC1CR) and two
16-bit timer registers (TREG1A and TREG1B). Reset does not affect TREG1A and
TREG1B.
TREG1A
15
14
13
(00010, 00011H)
12
11
10
9
8
7
6
5
TREG1AH (00011H)
4
3
2
1
0
TREG1AL (00010H)
Write only
TREG1B
(00012, 00013H)
TREG1BH (00013H)
TREG1BL (00012H)
Read/Write (Writing is capable only when PPG output mode)
7
TC1CR
TFF1
(00014H)
6
SCAP1
MCAP1
METT1
MPPG1
5
4
3
TC1S
2
1
TC1CK
0
TC1M
(Initial value: 0000 0000 )
00: Timer/external trigger timer/event counter mode
TC1M
TC1 operating mode select
01: Window mode
10: Pulse width measurement mode
11: PPG (Programmable pulse generate) output mode
NORMAL1/2, IDLE1/2 mode
DV1CK = 0
DV1CK = 1
DV1CK = 0
DV1CK = 1
SLOW,
SLEEP
mode
00
fc/211
fc/212
fs/23
fs/23
fs/23
01
7
fc/2
8
fc/2
7
fc/2
8
㸫
fc/2
4
fc/2
3
fc/2
4
㸫
DV7CK = 0
TC1CK
TC1 source clock select [Hz]
10
fc/2
3
fc/2
11
DV7CK = 1
External clock (TC1 pin input)
Write
only
00: Stop and counter clear
TC1S
TC1 start control
01: Command start
10: Reserved
11: External trigger start
SCAP1
Software capture control
0: 㸫
1: Software capture trigger
MCAP1
Pulse width measurement
mode control
0: Double edge capture
1: Single edge capture
METT1
External trigger timer mode
control
0: Trigger start
1: Trigger start & stop
PPG output control
0: Pulse
1: Single
Time F/F1 control for PPG
output mode
0: Clear
1: Set
MPPG1
TFF1
Note 1: fc: High-frequency clock [Hz], fs: Low-frequency clock [Hz]
Note 2: Writing to the lower byte of the timer registers (TREG1AL, TREG1BL), the comparison is inhibited until the upper
byte(TREG1AH, TREG1BH) is written. Only the lower byte of the timer registers can not be changed. After
writing to the upper byte, any match during 1 machine cycle (instruction execution cycle) is ignored.
Note 3: Set the mode, source clock, edge (including INT2ES), PPG control and timer F/F control when TC1 stops
(TC1S = 00).
Note 4: Software capture can be used in only timer and event counter modes. SCAP1 is automatically cleared to “0” after
capturing.
Note 5: Values to be loaded to timer registers must satisfy the following condition.
TREG1A>TREG1B>0(PPG output mode), TREG1A>0 (others)
Note 6: Always write “0” to TFF1 except PPG output mode.
Note 7: TC1CR and TREG1A are write-only registers and must not be used with any of the read-modify-write instructions
such as SET, CLR, etc.
Note 8: Writing to the TREG1B is not possible unless TC1 is set to the PPG output mode.
Note 9: Please use the auto-capture function in the operative condition of TC1.
A captured value may not be fixed if it's read after the execution of the timer stop or auto-capture
disable. Please read the capture value in a capture enabled condition.
Note 10:Since the up-counter value is captured into TC1DRB by the source clock of up-counter after
setting TC1CR<ACAP1> to “1”. Therefore, wait at least one cycle of the internal source clock
before reading TC1DRB for the first time.
Figure 2.6.2 Timer Registers and TC1 Control Register
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2.6.3
Function
Timer/Counter 1 has six operating modes: timer, external trigger timer, event counter,
window, pulse width measurement, programmable pulse generator output mode.
(1) Timer mode
In this mode, counting up is performed using the internal clock. The contents of
TREG1A are compared with the contents of up-counter. If a match is found, an
INTTC1 interrupt is generated, and the counter is cleared to “0”. Counting up resumes
after the counter is cleared. The current contents of up-counter can be transferred to
TREG1B by setting SCAP1 (bit 6 in TC1CR) to “1”(software capture function). SCAP1
is automatically cleared after capturing.
Table 2.6.1 Source Clock (Internal clock) for Timer/Counter 1 (Example: at fc = 12.5 MHz, fs = 32.8 kHz)
NORMAL1/2, IDLE1/2 Mode
DV7CK = 0
TC1CK
DV1CK = 0
Resolution
[μs]
00
01
10
163.84 μs
10.24 μs
0.64 μs
DV7CK = 1
DV1CK = 1
Maximum
Time Setting
10.8 s
0.64 s
41.92 ms
Resolution
[μs]
327.68 μs
20.48 μs
1.28 μs
DV1CK = 0
Maximum
Time Setting
21.5 s
1.28 s
83.84 ms
Resolution
[μs]
Maximum
Time Setting
244.14 μs
8
μs
0.5 μs
16.0 s
0.5 s
32.75 ms
DV1CK = 1
Resolution
[μs]
244.14 μs
16
μs
1
μs
Maximum
Time Setting
16.0 s
1.0 s
65.5 ms
SLOW, SLEEP Mode
TC1CK
00
01
10
Resolution
[μs]
Maximum
Time Setting [s]
244.14 μs
⎯
⎯
16.0 s
⎯
⎯
Example 1: Sets the timer mode with source clock fs/23 [Hz] and generates an interrupt 1 later (at fs = 32.8
kHz).
LDW
(TREG1A), 1000H
; Sets the timer register
(1 s ÷ 23/fs = 1000H)
SET
(EIRL). EF4
EI
; Enable INTTC1
LD
(TC1CR), 00010000B
; Starts TC1
Note:
TC1CR is a write-only register and must not be used with [SET(TC1CR).4]
instruction.
Example 2: Software capture
LD
(TC1CR), 01010000B
LD
WA, (TREG1B)
88CU74-62
;
;
SCAP1 ← 1 (Captures)
Reads the capture value
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TMP88CU74
Command start
Source clock
Up-counter
TREG1A
1
0
?
2
3
n−1 n 0
4
1
2
3
4
5
6
7
n
Match detect
INTTC1 interrupt
Counter clear
(a) Timer mode
Source clock
m−2
Up-counter
m−1
m+1
m
m+2
Capture
TREG1B
?
m
n−1
n
n+1
Capture
n
SCAP1
(b) Software capture
Figure 2.6.3 Timer Mode Timing Chart
(2) External trigger timer mode
In this mode, counting up is started by an external trigger. This trigger is the edge of
the TC1 pin input. Either the rising or falling edge can be selected with INT2ES in
EINTCR. Edge selection is the same as for INT3 pin. Source clock is an internal clock
selected with TC1CK. The contents of TREG1A is compared with the contents of
up-counter. If a match is found, an INTTC1 interrupt is generated, and the counter is
cleared to “0” and halted. The counter is restarted by the selected edge of the TC1 pin
input.
When METT1 (bit 6 in TC1CR) is “1”, inputting the edge to the reverse direction of
the trigger edge to start counting clears the counter, and the counter is stopped.
Inputting a constant pulse width can generate interrupts. When METT1 is “0”, the
reverse directive edge input is ignored. The TC1 pin input edge before a match
detection is also ignored.
The TC1 pin input has the same noise rejection as the INT3 pin; therefore, pulses of
7/fc [s] or less are rejected as noise. A pulse width of 24/fc [s] or more is required for
edge detection in NORMAL1, 2 or IDLE1, 2 mode. The noise rejection circuit is turned
off in SLOW and SLEEP modes. But, a pulse width of one machine cycle or more is
required.
Example 1: Detects rising edge in TC1 pin input and generates an interrupt 100 μs later. (at fc = 12.5 MHz,
DV1CK = 1)
LD
(EINTCR), 00000000B
; INT3ES ← 0 (rising edge)
LDW
(TREG1A), 004EH
; 100 μs ÷ 24/fc = 4EH
SET
(EIRL).EF4
; INTTC1 interrupt enable
EI
LD
(TC1CR), 00111000B
; TC1 external trigger start, METT1 = 0
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Example 2: Generates an interrupt, inputting “L” level pulse (pulse width: 4 ms or more) to the TC1 pin. (at
fc = 12.5 MHz, DV1CK = 1)
LD
(EINTCR), 00000100B
; INT2ES ← 1 (“L” level)
LDW
(TREG1A), 00C3H
; 4 ms ÷ 28/fc = C3H
SET
(EIRL).EF4
; INTTC1 interrupt enable
EI
LD
(TC1CR), 01110100B
; TC1 external trigger start, METT1 = 1
Count
start
Count
start
Trigger
TC1 pin input
INT2ES = 0 at the
rising edge
Trigger
Internal clock
Up-counter
TREG1A
0
1
?
2
n−1 n
3
0
1
2
3
n
Match detect
Counter clear
INTTC1 interrupt
(a) Trigger start (METTI = 0)
Counter
clear
Count
start
TC1 pin input
Count
start
Trigger
Trigger
INT2ES = 0
at the rising edge
Trigger
Internal clock
Up-counter
TREG1A
0
1
2
3
m
0
1
n−2 n−1 n
0
Note: m<n
n
Match detect
Counter clear
INTTC1 interrupt
(b) Trigger start and stop (METT1 = 1)
Figure 2.6.4 External Trigger Timer Mode Timing Chart
(3) Event counter mode
In this mode, events are counted at the edge of the TC1 pin input. Either the rising
or falling edge can be selected with INT2ES in EINTCR. Edge selection is the same as
for INT3 pin. The contents of TREG1A are compared with the contents of up-counter. If
a match is found, an INTTC1 interrupt is generated, and the counter is cleared. This
maximum applied frequency is shown in Table 2.6.2.
Setting SCAP1 to “1” transfers the current contents of up-counter to TREG1B
(software capture function). SCAP1 is automatically cleared after capturing.
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Command start
TC1 pin input
Up-counter
0
TREG1A
?
1
2
n−1
n
0
1
INT2ES = 1
at the falling
edge
2
n
Counter clear
Match detect
INTTC1 interrupt
Figure 2.6.5 Event Counter Mode Timing Chart
Table 2.6.2 Timer/Counter 1 External Clock Source
Maximum Applied Frequency [Hz]
NORMAL1/2, IDLE1/2 Mode
SLOW, SLEEP Mode
fc/24
fs/24
(4) Window mode
Counting up is performed on the rising edge of the pulse that is the logical AND-ed
product of the TC1 pin input (window pulse) and an internal clock. The contents of
TREG1A are compared with the contents of up-counter. If a match is found, an
INTTC1 interrupt is generated, and the counter is cleared. Positive or negative logic
for the TC1 pin input can be selected. Edge selection is the same as for INT3 pin.
Setting SCAP1 to “1” transfers the current contents of up-counter to TREG1B.
It is necessary that the maximum applied frequency be such that the counter value
can be analyzed by the program. That is; the frequency must be considerably slower
than the selected internal clock.
Command start
TC1 pin input
Internal clock
Up-counter
TREG1A
0
?
1
2
3
4
5
6
7 0
1
2
3
7
Match detect
INTTC1 interrupt
Counter clear
(a) Positive logic (at INT3ES = 0)
Command start
TC1 pin input
Internal clock
Up-counter
TREG1A
0
?
1
2
3
4
5
6
7
8
9 0 1
9
Match detect
Counter
clear
INTTC1 interrupt
(b) Negative logic (at INT3ES = 1)
Figure 2.6.6 Window Mode Timing Chart
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(5) Pulse width measurement mode
Counting is started by the external trigger (set to external trigger start by TC1S).
The trigger can be selected either the rising or falling edge of the TC1 pin input. The
source clock is used an internal clock. On the next falling (rising) edge, the counter
contents are transferred to TREG1B and an INTTC1 interrupt is generated. The
counter is cleared when the single edge capture mode is set. When double edge capture
is set, the counter continues and, at the next rising (falling) edge, the counter contents
are again transferred to TREG1B. If a falling (rising) edge capture value is required, it
is necessary to read out TREG1B contents until a rising (falling) edge is detected.
Falling or rising edge is selected with INT3ES, and single edge or double edge is
selected with MCAP1 (bit 6 in TC1CR).
Note: The first captured value after the timer starts may be read incorrectively, therefore, ignore the
first captured value.
Example: Duty measurement (resolution fc/27 [Hz] DV1CK = 0)
CLR
(INTTC1SW). 0
;
INTTC1 service switch initial setting
LD
(EINTCR), 00000000B
;
Sets the rise edge at the INT3 edge
LD
(TC1CR), 00000110B
;
Sets the TC1 mode and source clock
SET
(EIRL). EF4
;
Enables INTTC1
LD
(TC1CR), 00110110B
;
Starts TC1 with an external trigger at
CPL
(INTTC1SW). 0
;
Complements INTTC1 service switch
JRS
F, SINTTC1
LD
(HPULSE), (TREG1BL)
;
Reads TREG1B (“H” level pulse width)
LD
(HPULSE + 1), (TREG1BH)
EI
MCAP1=0
PINTTC1:
RETI
SINTTC1:
LD
(WIDTH), (TREG1BL)
;
Reads TREG1B (Period)
LD
(WIDTH + 1), (TREG1BH)
;
Duty calculation
RETI
VINTTC1:
DW
PINTTC1
WIDTH
HPULSE
TC1 pin
INTTC1SW
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Count start
Count start
TC1 pin input
(INT3ES = 0)
Trigger
Internal clock
Up-counter
0
1
2
3
4
n−1 n
0
1
2
Capture
n
TREG1B
INTTC1 interrupt
[Application] High or low pulse width measurement
(a) Single edge capture (MCAP1 = 1)
Count start
Count start
TC1 pin input
(INT3ES = 0)
Internal clock
Up-counter
0
1
2
3
4
n−1
n
n+1 n+2 n+3
m−2 m−1
Capture
TREG1B
n
m０
1
2
Capture
m
INTTC1 interrupt
[Application] 1. Period/Frequency measurement
2. Duty measurement
(b) Double edge capture (MCAP1 = 0)
Figure 2.6.7 Pulse Width Measurement Mode Timing Chart
(6) Programmable pulse generate (PPG) output mode
Counting is started by an edge of the TC1 pin input (either the rising or falling edge
can be selected) or by a command. The source clock is used an internal clock. First, the
contents of TREG1B are compared with the contents of the up-counter. If a match is
found, timer F/F1 output is toggled. When MPPG1 = 0, an INTTC1 interrupt is
generated. Next, timer F/F is again toggled and the counter is cleared by matching
with TREG1A. An INTTC1 interrupt is generated at this time. Timer F/F output is
connected to the P12 ( PPG ) pin. In the case of PPG output, set the P12 output latch to
“1” and configure as an output mode. Timer F/F1 is cleared to “0” during reset. The
timer F/F 1 value can also be set by TFF1 (bit 7 in TC1CR) and either a positive or
negative logic pulse output is available. Also, writing to the TREG1B is not possible
unless the timer/counter 1 is set to the PPG output mode.
Example: Pulse output “H” level 800 μs, “L” level 200 μs (at fc = 12.5 MHz, DV1CK = 0)
SET
(P1).2
; P12 output latch ← 1
LD
(P1CR), 00000100B
; Sets the P12 output mode
LD
(TC1CR), 10001011B
; Sets the PPG output mode
LDW
(TREG1A), 07D0H
; Sets the period (1 ms ÷ 0.64 μs = 061AH)
LDW
(TREG1B), 0190H
; Sets “L” level pulse width
(200 μs ÷ 0.64 μs = 0138H)
LD
(TC1CR), 10011011B
; Starts
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P12 output latch
Data output
TFF1
D
R
Q
Output enable
Set
TC1CR write strobe
Internal reset
Match with TREG1B
Match with TREG1A
P12 ( PPG ) pin
Clear Q
Toggle
B
Timer F/F1
Y
INTTC1 interrupt
A
S
TC1S clear
MPPG1
Figure 2.6.8 PPG Output
Internal clock
Up-counter
Command start
0
1
TREG1B
n
TREG1A
m
2
n
n+1
m 0
1
2
n
n+1
m 0
1
2
PPG pin output
INTTC1 interrupt
(a) Pulse
Count start
TC1 pin input
Trigger
External trigger start
Internal clock
Up-counter
0
TREG1B
n
TREG1A
m
1
n
n+1
m
0
PPG pin output
INTTC1 interrupt
[Application] One shot pulse output
(b) Single
Figure 2.6.9 PPG Output Mode Timing Chart
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2.7
16-Bit Timer/Counter 2 (TC2)
2.7.1
Configuration
MPX
TC2 pin
TC2S
H
Window
fc/223, fc/224 or fs/215
fc/213, fc/214 or fs/25
fc/28 or fc/29
fc/23 or fc/24
fc
fs
fc/2
A
B
C
Y
D
E
F
G
S
MPX
Clear
B
Timer/
Event counter
Y
A
16-bit up-counter
Source
S clock
TC2M
CMP
INTTC2
interrupt
Enable
3
TC2CK
Match detect
TC2S
Match detect control
TC2CR
TREG2
TC2 control register
16-bit timer register 2
TREG2H
write strobe
TREG2L
write strobe
Figure 2.7.1 Timer/Counter 2 (TC2)
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TMP88CU74
2.7.2
Control
The timer/counter 2 is controlled by a timer/counter 2 control register (TC2CR) and a
16-bit timer register 2 (TREG2). Reset does not affect TREG2.
TREG2
15
14
13
12
11
10
TREG2H (00017H)
(00016, 00017H)
9
8
7
6
5
4
3
2
TREG2L (00016H)
1
0
Write only
TC2CR
(00015H)
7
6
5
4
3
“0”
“0”
TC2S
TC2M
TC2 operating mode select
2
1
0
TC2CK
(Initial value: **00 00*0)
TC2M
0: Timer/Event counter mode
1: Window mode
NORMAL1/2, IDLE1/2 mode
DV7CK = 0
DV7CK = 1
DV1CK = DV1CK = DV1CK = DV1CK =
TC2CK
TC2 source clock select [Hz]
000
001
010
011
100
101
110
0
1
0
1
fc/223
fc/213
fc/28
fc/23
⎯
fs
⎯
fc/224
fc/214
fc/29
fc/24
⎯
fs
⎯
fs/215
fs/25
fc/28
fc/23
⎯
fs
⎯
fs/215
fs/25
fc/29
fc/24
⎯
fs
⎯
111
TC2S
TC2 start control
SLOW SLEEP
mode mode
fs/215
fs/25
⎯
⎯
fc
⎯
fc/2
fs/215
fs/25
⎯
⎯
⎯
⎯
⎯
Write
only
External clock (TC2 pin input)
0: Stop and counter clear
1: Start
Note 1: fc: High-frequency clock [Hz], fs: Low-frequency clock [Hz], fcgck: Gear clock [Hz], *: Don’t care
Note 2: Writing to the lower byte of timer register 2 (TREG2L), the comparison is inhibited until the upper byte (TREG2H)
is written. After writing to the upper byte, any match during 1 machine cycle (instruction execution cycle) is
ignored.
Note 3: Set the mode and source clock when the TC2 stops (TC2S = 0).
Note 4: Values to be loaded to the timer register must satisfy the following condition.
TREG2>0 (TREG215 to 11>0 at warm-up)
Note 5: “fcgck” can be selected as the source clock only in the timer mode during the SLOW mode.
Note 6: TC2CR and TREG2 are write-only registers and must not be used with any of the read-modify-write instructions
such as SET, CLR, etc.
Note 7: It recommends when used as an TC2CK = <100>, at fc ≤ 8 MHz, and used as an TC2CK = <110>,
at fc = 12.5 MHz.
Figure 2.7.2 Timer Register 2 and TC2 Control Register
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2.7.3
Function
The timer/counter 2 has three operating modes: timer, event counter and window modes.
Also timer/counter 2 is used for warm-up when switching from SLOW mode to NORMAL2
mode.
(1) Timer mode
In this mode, the internal clock is used for counting up. The contents of TREG2 are
compared with the contents of up-counter. If a match is found, a timer/counter 2
interrupt (INTTC2) is generated, and the counter is cleared. Counting up is resumed
after the counter is cleared.
Also, when “fcgck” is selected as the source clock during SLOW mode, the lower 11
bits of TREG2 are ignored and an INTTC2 interrupt is generated by matching the
upper 5 bits. Thus, in this case, only the TREG2H setting is necessary.
Table 2.7.1 Source Clock (Internal clock) for Timer/Counter 2 (at fc = 12.5 MHz, fs = 32.8 kHz)
NORMAL1/2, IDLE1/2 Mode
DV7CK = 0
DV1CK = 0
TC2CK
000
001
010
011
100
101
Resolution
Maximum
Time Setting
671
ms
655.36 μs
20.48 μs
0.64 μs
−
12.2 h
43.0 s
1.34 s
41.92 ms
−
30.5 μs
2
s
000
001
01*
100
110
101
Note:
Resolution [s]
1
s
0.98 ms
−
125
160
ns (Note)
ns (Note)
−
DV1CK = 0
Resolution
Maximum
Time Setting
1.34 s
1.31 ms
40.96 μs
1.28 μs
−
24.4 h
1.4 min
2.7 s
83.8 ms
−
30.5 μs
SLOW Mode
TC2CK
DV7CK = 1
DV1CK = 1
2
s
DV1CK = 1
Resolution
Maximum
Time Setting
Resolution
Maximum
Time Setting
1
s
0.98 ms
16
μs
0.5 μs
−
18.2 h
1.07 min
1.05 s
32.75 ms
−
1
s
0.98 ms
32
μs
1
μs
−
18.2 h
1.07 min
2.1 s
65.5 ms
−
30.5 μs
2
s
30.5 μs
2
s
SLEEP Mode
Maximum
Time Setting
Resolution [s]
Maximum
Time Setting
18.2 h
1.07 min
−
−
−
−
1
s
0.98 ms
−
−
−
−
18.2 h
1.07 min
−
−
−
−
fc and fc/2 can be used only in the timer mode. It is used for warm-up when switching from SLOW
mode to NORMAL2 mode. (at fc = 8 MHz, TC2CK = <100>)
Example: Sets the timer mode with source clock fc/24 [Hz] and generates an interrupt every 25 ms
(at fc = 12.5 MHz, DV1CK = 1).
LDW
(TREG2), 4C46H
; Sets TREG2 (25 ms ÷ 24/fc = 4C46H)
SET
(EIRH). EF14
; Enables INTTC2 interrupt
EI
LD
(TC2CR), 00101100B
; Starts TC2
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(2) Event counter mode
In this mode, events are counted on the rising edge of the TC2 pin input. The
contents of TREG2 are compared with the contents of the up-counter. If a match is
found, an INTTC2 interrupt is generated, and the counter is cleared. The maximum
frequency applied to the TC2 pin is shown in Table 2.7.2. Two or more machine cycles
are required for both the “H” and “L” levels of the pulse width.
Example: Sets the event counter mode and generates an INTTC2 interrupt 640 counts later.
LDW
(TREG2), 640
; Sets TREG2
SET
(EIRH). EF14
; Enables INTTC2 interrupt
EI
LD
(TC2CR), 00111100B
; Starts TC2
Table 2.7.2 Timer/Counter 2 External Clock Source
Maximum Applied Frequency [Hz]
NORMAL1/2, IDLE1/2 Mode
SLOW, SLEEP Mode
fc/24
fs/24
(3) Window mode
In this mode, counting up is performed on the rising edge of an internal clock during
TC2 external pin input(window pulse) is “H” level. The contents of TREG2 are
compared with the contents of up-counter. If a match is found, an INTTC2 interrupt is
generated, and the up-counter is cleared.
The maximum applied frequency (TC2 input) must be considerably slower than the
selected internal clock.
Example: Generates an interrupt, inputting “H” level pulse width of 120 ms or more. (at fc = 12.5 MHz,
DV1CK = 1)
LDW
(TREG2), 0056H
; Sets TREG2 (120 ms ÷ 214/fc = 0056H)
SET
(EIRH). EF14
; Enables INTTC2 interrupt
EI
LD
(TC2CR), 00100101B
; Starts TC2
TC2 pin input
Internal clock
Up-counter
TREG2
0
1
2
n−3
n−2
n−1 n 0
1
2
3
n
Match detect
Counter clear
INTTC2 interrupt
Figure 2.7.3 Window Mode Timing Chart
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2.8
8-Bit Timer/Counter 3 (TC3)
2.8.1
Configuration
Inhibit
Rising
Edge
detector
Capture
control
Falling
TC3M
INTTC3
interrupt
TC3S
TC3IN
INT4ES
TC3 pin
Clear
S
A
Y
B
MPX
fc/212, fc/213 or fs/24
fc/210, fc/211 or fs/22
fc/27, fc/28
H
AY
B
C
S
Source clock
Overflow
8-bit up-counter
Comparator
TC3M
CMP
Match
Capture
2
TREG3B
SCAP
TREG3A
Capture
8-bit timer register 3A, B
TC3CK
TC3S
TC3CR
TC3 control register
Figure 2.8.1 Timer/Counter 3 (TC3)
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2.8.2
Control
The timer/counter 3 is controlled by a timer/counter 3 control register (TC3CR) and two
8-bit timer registers (TREG3A and TREG3B).
TREG3A
7
6
5
4
3
2
1
0
Read/Write
(00018H)
TREG3B
Read only
(00019H)
TC3CR
(0001AH)
7
6
5
4
“0”
SCAP
“0”
TC3S
TC3M
TC3
operation mode set
3
2
TC3CK
1
0
“0”
TC3M
(Initial value: *0*0 00*0 )
0: Timer/event counter
1: Capture
NORMAL1/2, IDLE1/2 mode
DV7CK = 0
TC3CK
TC3
source clock select [Hz]
DV7CK = 1
DV1CK = 0 DV1CK = 1 DV1CK = 0 DV1CK = 1
00
01
10
fc/212
fc/210
fc/27
11
fc/213
fc/211
fc/28
fs/24
fs/22
fs/27
fs/24
fs/22
fs/28
SLOW,
SLEEP
mode
fs/24
⎯
⎯
Write
only
External clock (TC3 pin input)
TC3S
TC3
start select
0: Stop and clear
1: Start
SCAP
Software capture control
0: ⎯
1: Software capture trigger
Note 1: fc: High-frequency clock [Hz], fs: Low-frequency clock [Hz], *: Don’t care
Note 2: Set the mode, the source clock and the edge selection (INT3ES) when the TC3 stops (TC3S = 0).
Note 3: Software capture can be used only in the timer and event counter mode. SCAP is automatically cleared to “0”
after capturing.
Note 4: Values to be loaded into timer register 3A must satisfy the following condition.
TREG3A>0 (in the timer and event counter mode)
Note 5: TC3CR is a write-only register and must not be used with any of read-modify-write instructions such as SET,
CLR, etc.
Figure 2.8.2 Timer Register 3 and TC3 Control Register
2.8.3
Function
The timer/counter 3 has three operating modes: timer, event counter, and capture mode.
When it is used in the capture mode, the noise rejection time of TC3 pin input can be set
by remote control receive control register.
(1) Timer mode
In this mode, the internal clock is used for counting up. The contents of TREG3A are
compared with the contents of up-counter. If a match is found, a timer/counter 3
interrupt (INTTC3) is generated, and the up-counter is cleared. Counting up resumes
after the up-counter is cleared. The current contents of up-counter are loaded into
TREG3B by setting SCAP (bit 6 in TC3CR) to “1”. SCAP is automatically cleared after
capturing.
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TMP88CU74
Table 2.8.1 Source Clock (Internal Clock) for Timer/Counter 3 (Example: at fc = 12.5 MHz, fs = 32.8 kHz)
NORMAL1/2, IDLE1/2 Mode
DV7CK = 0
TC3CK
00
01
10
TC3CK
00
DV1CK = 0
Maximum
Resolution
Setting Time
[μs]
[ms]
327.68
81.92
10.24
DV7CK = 1
DV1CK = 1
Maximum
Resolution
Setting Time
[μs]
[ms]
167.8
41.7
5.2
655.36
163.84
10.48
83.6
20.9
2.6
DV1CK = 0
Maximum
Resolution
Setting Time
[μs]
[ms]
488.28
122.07
8
124.5
31.1
2.0
DV1CK = 1
Maximum
Setting Time
[ms]
Resolution
[μs]
488.28
122.07
16
124.5
31.1
4.1
SLOW, SLEEP Mode
Maximum
Setting Time
Resolution [μs]
[ms]
488.28
124.5
(2) Event counter mode
In this mode, the TC3 pin input pulses are used for counting up. Either the rising or
falling edge can be selected. Edge selection is the same as for INT3 pin. The contents of
TREG3A are compared with the contents of the up-counter. If a match is found, an
INTTC3 interrupt is generated and the counter is cleared.
The maximum applied frequency is shown in Table 2.8.2. Two or more machine
cycles are required for both the high and low levels of the pulse width.
The current contents of up-counter are loaded into TREG3B by setting SCAP (bit 6
in TC3CR) to “1”. SCAP is automatically cleared to “0” after capturing.
Example: Generates an interrupt every 0.5 s, inputting 50 Hz pulses to the TC3 pin.
LD
(TREG3A), 19H
; 0.5 s ÷ 1/50 = 25 = 19H
LD
(TC3CR), 00011110B
; Starts TC3
Table 2.8.2 Source Clock (External Clock) for Timer/Counter
Maximum Applied Frequency [Hz]
NORMAL1/2, IDLE1/2 Mode
SLOW, SLEEP Mode
fc/24
fs/24
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TMP88CU74
(3) Capture mode
The pulse width, period and duty of the TC3 pin input are measured in this mode,
which can be used in decoding the remote control signals or distinguishing AC 50/60
Hz, etc. The counter is free running by the internal clock. On the rising (falling) edge of
the TC3 pin input, the current contents of counter is loaded into TREG3A, then the
up-counter is cleared to “0” and an INTTC4 interrupt is generated. On the falling
(rising) edge of the TC3 pin input, the current contents of the counter is loaded into
TREG3B. In this case, counting continues. On the next rising (falling) edge of the TC3
pin input, the current contents of counter are loaded into TREG3A, then the counter is
cleared again and an interrupt is generated. If the counter overflows before the edge is
detected. FFH is set into TREG3A, and the counter is cleared and an INTTC3 interrupt
is generated. During interrupt processing, it can be determined whether or not there is
an overflow by checking whether or not the TREG3A value is FFH. Also, after an
interrupt (capture to TREG3A, or overflow detection) is generated, capture and
overflow detection are halted until TREG3A has been read out; however, the counter
continues. As reading out TREG3A resumes capture/overflow detection, TREG3B must
be beforehand read out.
Source clock
Up-counter
k−2
k−1 k 0
1
m−1
m
m+1
1
n−1 n 0
2
3
FE FF 0
1
2
3
TC3 pin input
TREG3A
TREG3B
INTTC3 interrupt
n
k
m
Capture
FF (Overflow)
FE
Capture
Overflow
Reading TREG3A
Figure 2.8.3 Capture Mode Timing Chart (at INT4ES = 0)
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2.9
8-Bit Timer/Counter 4 (TC4)
2.9.1
Configuration
INT4ES
TC4 pin
S
A
Y
TC4S
B
MPX
fc/211, fc/212 or fs/23
fc/27 or fc/28
fc/23 or fc/24
D
A
B
C
Y
S
3
TFF4
2
Source
clock
TC4S
TC4CK
Clear
Overflow
8-bit up-counter
Comparator
Match
Timer F/F4
PWM4 / PDO 4
CMP
TC4M
2
Toggle
Toggle Set Clear Set
Clear
A
TC4CR
TREG4
TC4 control register
8-bit timer register 4
Y
pin
Q
B
S
PWM output
mode
INTTC4
interrupt
TC4M1
Decoder
2
TFF4
Figure 2.9.1 Timer/Counter 4 (TC4)
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2.9.2
Control
The timer/counter 4 is controlled by a timer/counter 4 control register (TC4CR) and an
8-bit timer register 4 (TREG4). Reset does not affect TREG4.
TREG4
7
6
5
4
3
2
1
0
Write only
(0001BH)
TC4CR
(0001CH)
7
6
TFF4
TC4M
5
4
“0”
TC4S
TC4 operating mode select
3
2
1
TC4CK
0
TC4M
(Initial value: 00*0 0000 )
00: Timer
01: Reserved
10: Programmable divider output (PDO) mode
11: Pulse width modulation (PWM) output mode
NORMAL1/2, IDLE1/2 mode
DV7CK = 0
TC4CK
TC4S
TFF4
TC4 source clock select [Hz]
DV7CK = 1
SLOW,
SLEEP
DV1CK = 0
DV1CK = 1
DV1CK = 0
DV1CK = 1
mode
fc/211
fc/27
fc/212
fc/28
fs/23
fc/27
fs/23
fc/28
fs/23
⎯
10
fc/23
fc/24
fc/23
fc/24
⎯
11
Reserved
00
01
TC4 start control
0: Stop and counter clear
1: Start
Timer F/F4 control
00: Clear
01: Reserved
10: Reserved
11: ⎯ (Note 3)
Write
only
Note 1: fc: High-frequency clock [Hz], fs: Low-frequency clock [Hz], *: Don’t care
Note 2: Set the operating mode, the source clock selection, the edge selection (INT4ES) and timer F/F4 control when
the TC4 stops (TC4S = 0)
Note 3: Set TFF4 to “11” in the timer and event counter mode and PWM mode.
Note 4: Values to be loaded to the timer register must satisfy the following condition.
0<TREG4 in others
Note 5: TC4CR is a write-only register and must not be used with any of the read-modify-write instructions such as SET,
CLR, etc.
Figure 2.9.2 Timer Register 4 and TC4 Control Register
2.9.3
Function
The timer/counter 4 has four operating modes: timer, event counter, programmable
divider output, and PWM output mode.
(1) Timer mode
In this mode, the internal clock is used for counting up. The contents of TREG4 are
compared with the contents of up-counter. If a match is found, an INTTC4 interrupt is
generated and the up-counter is cleared to “0”. Counting up resumes after the
up-counter is cleared.
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Table 2.9.1 Source Clock (Internal clock) for Timer/Counter 4 (Example: at fc = 12.5 MHz, fs = 32.8 kHz)
NORMAL1/2, IDLE1/2 Mode
DV7CK = 0
TC4CK
00
01
10
DV1CK = 0
DV7CK = 1
DV1CK = 1
DV1CK = 0
DV1CK = 1
Resolution
[μs]
Maximum
Setting Time
[s]
Resolution
[μs]
Maximum
Setting Time
[s]
Resolution
[μs]
Maximum
Setting Time
[s]
Resolution
[μs]
Maximum
Setting Time
[s]
163.84 μs
10.24 μs
0.64 μs
41.7 ms
2.6 ms
163.2 μs
327.68 μs
20.48 μs
1.28 μs
83.6 ms
5.2 ms
326 μs
244.14 μs
10.24 μs
0.64 μs
62.2 ms
2.6 ms
163.2 μs
244.14 μs
20.48 μs
1.28 μs
62.2 ms
5.2 ms
326
μs
SLOW, SLEEP Mode
TC4CK
Resolution
[μs]
Maximum
Setting Time
[s]
00
01
10
244.14 μs
―
―
62.2 ms
―
―
(2) Programmable divider output (PDO) mode
The internal clock is used for counting up. The contents of TREG4 are compared with
the contents of the up-counter. If a match is found, the timer F/F 4 output is toggled
and the counter is cleared. Timer F/F 4 output is inverted and output to the P14
( PPO4 ) pin. When programmable divider output is executed, P14 output latch is set to
“1”. This mode can be used for approximate 50% duty pulse output. Timer F/F 4 can be
initialized by program, and it is initialized to “0” during reset. An INTTC4 interrupt is
generated each time the PDO output is toggled.
Example: Output a 1024 Hz pulse (at fc = 12.5 MHz)
SET
(P1). 4
LD
(P1CR), 00010000B
LD
(TREG4), 5FH
LD
(TC4CR), 00010010B
;
;
;
;
P14 output latch ← 1
Set output mode to P14
1/1024 ÷ 27/fc = 5FH
Starts TC4
Internal clock
Up-counter
TREG4
0
1
2
n 0
1
2
n 0
1
2
n 0
1
2
n 0
1
n
Match detect
Timer F/F4
PDO 4 pin output
INTTC4 interrupt
Figure 2.9.3 PDO Mode Timing Chart
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(3) Pulse width modulation (PWM) output mode
PWM output with a resolution of 8 bits is possible. The internal clock is used for
counting up. The contents of TREG4 are compared with the contents of up-counter. If a
match is found, the timer F/F 4 output is toggled. Counting up resumes. And, when an
overflow occurs, the timer is again toggled and the counter is cleared. Timer F/F 4
output is inverted and output to the P14 ( PWM4 ) pin. When programmable divider
output is executed, P14 output latch is set to “1”. An INTTC4 interrupt is generated
when an overflow occurs.
TREG4 is configured a 2-stage shift register and, during output, will not switch until
one output cycle is completed even if TREG4 is overwritten; therefore, output can be
altered continuously. Also, the first time, TREG4 is shifted by setting TC4S (bit 4 in
TC4CR) to “1” after data are loaded to TREG4.
Note:
Do not rewrite the contents of TREG4 at only an INTTC4 interrupt generation cycle.
The contents of TREG4 is rewritten by the INTTC4 interrupt service routine.
Internal clock
0
Up-counter
TREG4
1
n
n+1
FF
0
1
n/n
n
n+1
FF
0
n/m
m−1 m
1
m/m
Match
Shift
Overwrite
Timer F/F4
PWM4 pin output
INTTC4 interrupt
1 cycle
Figure 2.9.4 PWM Output Mode Timing Chart
Table 2.9.2 PWM Output Mode (Example: fc = 12.5 MHz)
NORMAL1/2, IDLE1/2 Mode
DV7CK = 0
TC4CK
00
01
10
DV1CK = 0
DV7CK = 1
DV1CK = 1
DV1CK = 0
DV1CK = 1
Resolution
[μs]
Repeat
Cycle [ms]
Resolution
[μs]
Repeat
Cycle [ms]
Resolution
[μs]
Repeat
Cycle [ms]
Resolution
[μs]
Repeat
Cycle [ms]
163.84 μs
10.24 μs
0.64 μs
41.7 ms
2.6 ms
163.2 μs
327.68 μs
20.48 μs
1.28 μs
83.6 ms
5.2 ms
326 μs
244.14 μs
―
―
62.5 ms
―
―
244.14 μs
―
―
62.5 ms
―
―
SLOW, SLEEP Mode
TC4CK
Resolution
[μs]
Repeat Cycle
[ms]
00
01
10
244.14 μs
―
―
62.5 ms
―
―
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2.10 Serial Bus Interface (SBI-ver.C)
The TMP88CU74 has a 1-channel serial bus interface which employs a clocked-synchronous
8-bit serial bus interface and an I2C bus (a bus system by Philips).
The serial bus interface is connected to an external device through P31 (SDA) and P30 (SCL)
in the I2C bus mode; and through P32 ( SCK0 ), P32 (SO0) and P30 (SI0) in the
clocked-synchronous 8-bit SIO mode.
The serial bus interface pins are also used for the P3 port. When used for serial bus interface
pins, set the P3 output latches of these pins to “1”, and control inputs and outputs of these pins
by the I/O control register. When not used for serial bus interface pins, the pin is used as a
normal I/O port.
2.10.1
Configuration
INTSBI interrupt
SCL
SCK
SIO
clock
control
fc/4
Noise
rejection
circuit
Input/
output
control
P32
( SCK 0 )
Divider
I2C bus
clock
sync.
+
Control
SBICR2/
SBISR
Shift
register
I2CAR
SBI control register 2/ I2C bus
SBI status register
address register
SO0
SIO
data control
Transfer
control
circuit
I2C bus
data control
SBIDBR
SBICR1
SBI data
buffer register
SBI control register 1
SI0
Noise
rejection
circuit
P31
(SDA/SO0)
P30
(SCL/SI0)
SDA
Figure 2.10.1 Serial Bus Interface (SBI-ver.C)
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2.10.2
Control
The following registers are used to control the serial bus interface and monitor the
operation status.
•
Serial bus interface control register 1 (SBICR1)
•
Serial bus interface control register 2 (SBICR2)
•
Serial bus interface data buffer register (SBIDBR)
•
I2C bus address register (I2CAR)
•
Serial bus interface status register (SBISR)
The above registers differ depending on an mode to be used. Refer to Section “2.10.4 I2C
bus mode control” and “2.10.6 Clocked-synchronous 8-bit SIO mode control”.
2.10.3
The Data Format in the I2C Bus Mode
The data format in the I2C bus mode are shown in Figure 2.10.2.
(a) Addressing format
1
8 bits
S
Slave address
R A
/ C
W K
1 to 8 bits
1
1 to 8 bits
Data
A
C
K
Data
A
C P
K
1 or more
1
(b) Addressing format (with restart)
8 bits
S
Slave address
1
R A
/ C
W K
1 to 8 bits
Data
1
A
C S
K
8 bits
Slave address
1 or more
1
1
R A
/ C
W K
1 to 8 bits
Data
1
A
C P
K
1 or more
1
(c) Free data format
8 bits
S
Data
1
1
A
C
K
1 to 8 bits
Data
1
A
C
K
1 to 8 bits
Data
1
A
C P
K
1 or more
S: Start condition
R/ W : Direction bit
ACK: Acknowledge bit
P: Stop condition
2
Figure 2.10.2 Data Format in I C Bus Mode
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I2C Bus Mode Control
2.10.4
The following registers are used to control the serial bus interface (SBI-ver.C) and
monitor the operation status in the I 2C bus mode.
Serial Bus Interface Control Register 1
SBICR1
7
(0020H)
6
5
BC
4
3
ACK
SWRST
2
1
0
SCK
(Initial value: 0000 0000)
ACK = 0
BC
ACK
SWRST
SCK
Number of transferred bits
ACK = 1
BC
Number of
Clock
Bits
Number of
Clock
Bits
000
8
8
9
8
001
1
1
2
1
010
2
2
3
2
011
3
3
4
3
100
4
4
5
4
101
5
5
6
5
110
6
6
7
6
111
7
7
8
7
Write
only
Acknowledge mode
specification
0: Acknowledge not returned to transmitter.
1: Acknowledge returned to transmitter.
Read/
Write
Initiate a internal of SBI
0: 1: Initialized (Clearing "0" after initialized)
Read/
Write
Serial clock selection
000:Reserved (Note4)
001:Reserved (Note4)
010: 91.9 kHz
011: 47.3 kHz
100: 24.0 kHz
101: 12.1 kHz
110: 6.08 kHz
111: Reserved
Write
only
at fc = 12.5 MHz (Output on SCL pin)
Note 1: fc: High-frequency clock [Hz]
Note 2: Set the BC to “000” before switching to 8-bit SIO bus mode.
Note 3: SBICR1 is write-only registers, which cannot be used with any of read-modify-write instruction such as bit
manipulation, etc.
Note 4: This I2C bus circuit does not support the Fast mode. It supports the Standard mode only. Although the
I2C bus circuit itself allows the setting of a baud rate over 100 kbps, the compliance with the I2C
specification is not guaranteed in that case.
Serial Bus Interface Data Buffer Register
SBIDBR
7
6
5
4
3
2
1
0
(0021H)
R/W
Note 1: For writing transmitted data, start from the MSB (bit 7).
Note 2: Cannot read the data which was written into SBIDBR, since a write data buffer and a read data buffer are
independent in SBIDBR. Therefore, SBIDBR cannot be used with any of read-modify-write instructions such
as bit manipulation, etc.
Note3: The data which was written into SBIDBR is cleared to “0” when INTSBI is generated.
I2C bus Address Register
7
I2CAR
6
5
4
3
2
1
SA2
SA1
SA0
Slave address
(0022H)
SA6
SA5
SA4
SA3
SA
TMP88CU74 slave address
selection
ALS
Address recognition mode
specification
0
ALS
(Initial value: 0000 0000)
0: Slave address recognition
1: Non slave address recognition
Write
only
Note: I2CAR is write-only register, which cannot be used with any of read-modify-write instruction such as bit
manipulation, etc.
Figure 2.10.3 Serial Bus Interface Control Register 1, Serial Bus Interface Data Buffer Register and
I2C Bus Address Register in the I2C Bus Mode
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Serial Bus Interface Control Register 2
7
6
5
SBICR2
(0023H)
MST
MST
TRX
BB
PIN
SBIM
Note 1:
TRX
BB
4
3
2
PIN
SBIM
1
0
“0”
“0”
(Initial value: 0001 00**)
0: Slave
1: Master
0: Receiver
Transmitter/Receiver selection 1: Transmitter
0: Stop condition
Start/Stop generation
1: Start condition
Cancel interrupt service
0: ⎯ (cannot be cleared to “0”)
request
1: Cancel interrupt service request
00: Port mode (serial bus interface output disable)
Serial bus interface operating 01: Clocked-synchronous 8-bit SIO mode
mode selection
10: I2C bus mode
11: Reserved
Master/Slave selection
*: Don’t care
Note 2:
Switch a mode to port after confirming that the bus is free.
Note 3:
Switch a mode to I2C bus mode after confiming that input signals via port are high level.
Note 4:
Write
only
SBICR2 has write-only register bits, which can not be used with any of read-modify-write instructions such as
bit manipulation, etc.
Note 5:
SBISR
(0023H)
Clear bits 1 and 0 in SBICR2 to “0”.
7
6
5
4
3
2
1
0
MST
TRX
BB
PIN
AL
AAS
AD0
LRB
MST
TRX
BB
PIN
AL
AAS
AD0
LRB
Master/Slave selection status
monitor
Transmitter/receiver selection
status monitor
Bus status monitor
Interrupt service request
status monitor
Arbitration loss detection
monitor
Slave address match
detection monitor
“GENERAL CALL” detection
monitor
Last received bit monitor
(Initial value: 0001 0000)
0: Slave
1: Master
0: Receiver
1: Transmitter
0: Bus free
1: Bus busy
0: INTSBI occurs
1: INTSBI not occurs
0: Arbitration loss undetected
1: Arbitration loss detected
0: Slave address unmatch or “GENERAL CALL” undetected
1: Slave address match or “GENERAL CALL” detected
0: “GENERAL CALL” undetected
1: “GENERAL CALL” detected
0: Last received bit “0”
1: Last received bit “1”
Read
only
Figure 2.10.4 Serial Bus Interface Control Register 2 and Serial Bus Interface Status Register
2
in the I C Bus Mode
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(1) Acknowledge mode specification
Set the ACK (bit 4 in SBICR1) to “1” for operation in the acknowledge mode. The
TMP88CU74 generates an additional clock pulse for an acknowledge signal when
operating in the master mode. In the transmitter mode during the clock pulse cycle, the
SDA pin is released in order to receive the acknowledge signal from the receiver. In the
receiver mode during the clock pulse cycle, the SDA pin is set to the low level in order
to generate the acknowledge signal.
Reset the ACK for operation in the non-acknowledge mode. The TMP88CU74 does
not generate a clock pulse for the acknowledge signal when operating in the master
mode.
In the acknowledge mode, the TMP88CU74 counts a clock pulse for the acknowledge
signal when operating in the slave mode. During the clock pulse, when the received
slave address is the same as the value set at the I2CAR or when a GENERAL CALL is
received, the SDA pin is set to the low level in order to generate the acknowledge
signal.
In the transmitter mode during the clock pulse cycle after matching the slave
addresses or receiving a GENERAL CALL, the SDA pin is released in order to receive
the acknowledge signal from the receiver. In the receiver mode during the clock pulse
cycle, the SDA pin is set to the low level in order to generate the acknowledge signal.
In non-acknowledge mode, the TMP88CU74 does not count a clock pulse for the
acknowledge signal when operating in the slave mode.
(2) Number of transfer bits
The BC (bits 7 to 5 in SBICR1) is used to select a number of bits for transmitting and
receiving data.
Since the BC is cleared to “000” as a start condition, a slave address and direction bit
transmissions are always executed in 8 bits. Other than these, the BC retains a
specified value.
(3) Serial clock
a. Clock source
The SCK (bits 2 to 0 in SBICR1) is used to select a maximum transfer frequency output
from the SCL pin in the master mode. Set a communication baud rate that meets the I2C
bus specification, such as the shortest pulse width of tLOW, based on the equations shown
below.
In both master mode and slave mode, a pulse width of at least 4 machine cycles is
required for both high and low levels.
tHIGH
tLOW
1/fscl
6&.
n
tLOW = 2 /fc
tHIGH = 2n /fc + 8/fc
fscl = 1/(tLOW + tHIGH)
fc: +LJKIUHTXHQF\FORFN
(Bits 2 to 0 in the SBICR1)
000
001
010
011
100
101
110
n
4
5
6
7
8
9
10
Figure 2.10.5 Clock Source
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b.
Clock synchronization
In the I2C bus mode, in order to drive a bus with a wired AND, a master device
which pulls down a clock pulse to low will, in the first place, invalidate a clock
pulse of another master device which generates a high-level clock pulse. The
master device with a high-level clock pulse needs to detect the situation and
implement the following procedure.
The TMP88CU74 has a clock synchronization function for normal data transfer
even when more than one master exists on a bus.
The example explains clock synchronization procedures when two masters
simultaneously exist on a bus.
SCL pin (Master 1)
Wait
Count start
Count reset
SCL pin (Master 2)
Count reset
SCL (Bus)
a
b
c
Figure 2.10.6 Clock Synchronization
As Master 1 pulls down the SCL pin to the low level at point “a”, the SCL line of
the bus becomes the low level. After detecting this situation, Master 2 resets
counting a clock pulse in the high level and sets the SCL pin to the low level.
Master 1 finishes counting a clock pulse in the low level at point “b” and sets the
SCL pin to the high level. Since Master 2 holds the SCL line of the bus at the low
level, Master 1 waits for counting a clock pulse in the high level. After Master 2
sets a clock pulse to the high level at point “c” and detects the SCL line of the bus
at the high level, Master 1 starts counting a clock pulse in the high level.
The clock pulse on the bus is deteminded by the master device with the shortest
high-level period and the master device with the longest low-level period from
among those master devices connected to the bus.
(4) Slave address and address recognition mode specification
When the serial bus interface circuit is used with an addressing format to recognize
the slave address, clear the ALS (bit 0 in I2CAR) to “0”, and set the SA (bits 7 to 1 in
I2CAR) to the slave address.
When the serial bus interface circuit is used with a free data format not to recognize
the slave address, set the ALS to “1”. With a free data format, the slave address and the
direction bit are not recognized, and they are processed as data from immediately after
start condition.
(5) Master/slave selection
Set the MST (bit 7 in SBICR2) to “1” for operating the TMP88CU74 as a master
device.
Reset the MST for operation as a slave device. The MST is cleared to “0” by the
hardware after a stop condition on the bus is detected or arbitration is lost.
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(6) Transmitter/Receiver selection
Set the TRX (bit 6 in SBICR2) to “1” for operating the TMP88CU74 as a transmitter.
Reset the TRX for operation as a receiver. When data with an addressing format is
transferred in the slave mode, the TRX is set to “1” if the direction bit (R/ W ) sent from
the master device is “1”, and is cleared to “0” if the bit is “0”. In the master mode, after
an acknowledge signal is returned from the slave device with the hardware, the TRX is
set to “0” if a transmitted direction bit is “1”, and set to “1” if it is “0”. When an
acknowledge signal is not returned, the current condition is maintained.
The TRX is cleared to “0” by the hardware after a stop condition on the bus is
detected or arbitration is lost.
The following table shows TRX changing conditions and TRX value after changing.
Mode
TRX after
Changing
Direction Bit
Conditions
0
When the received slave address is the
same as I2CAR
Slave mode
1
0
Master mode
0
1
1
When the ACK signal is returned
1
0
When the serial bus interface circuit is used with a free data format, the TRX is not
changed by hardware since the slave address and the direction bit are not recognized,
and they are processed as data from immediately after start condition.
(7) Start/Stop condition generation
A start condition and 8-bit data are output on the bus by writing “1” to the MST, TRX
and BB when the BB (bit 5 in SBICR2) is “0”. It is necessary to set the transmitting
data to the data buffer register and “1” to ACK beforehand.
SCL pin
1
2
3
4
5
6
7
SDA pin
A6
A5
A4
A3
A2
A1
A0
Start condition
slave address and the direction bit
8
9
R/W
Acknowledge signal
Figure 2.10.7 Start Condition Generation and Slave Address Generation
When the BB is “1”, sequence of generating a stop condition is started by writing “1”
to the MST, TRX, and PIN, and “0” to the BB. Do not modify the contents of MST, TRX,
BB and PIN until a stop condition is generated on a bus.
SCL pin
SDA pin
Stop condition
Figure 2.10.8 Stop Condition Generation
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The bus condition can be indicated by reading the contetns of the BB (bit 5 in SBISR).
The BB is set to “1” when a start condition on a bus is detected and is cleared to “0”
when a stop condition is detected.
(8) Interrupt service request cancel
In the master mode, a serial bus interface interrupt request (INTSBI) occurs after
the number of clocks which is specified by the BC and ACK has been transmitted.
In the slave mode, when the received slave address is the same as the value set at
the I2CAR, after outputting the acknowledge signal when a GENERAL CALL is
received, or when data transfer is complete after matching the slave addresses or
receiving a GENERAL CALL, an INTSBI interrupt request occurs.
When a serial bus interface interrupt request occurs, the PIN (bit 4 in SBISR) is
cleared to “0”. During the time that the PIN is “0”, the SCL pin is pulled down to the
low level.
Either writing/reading data to/from the SBIDBR sets the PIN to “1”.
The time from the PIN being set to “1” until the SCL pin is released takes tLOW.
Although the PIN (bit 4 in SBICR2) can be set to “1” by the program, the PIN is not
set to “0” when “0” is written.
(9) Serial bus interface operating mode
The SBIM (bits 3, 2 in SBICR2) is used to specify the serial bus interface operation
mode. Set the SBIM to “10” after confirming that the serial bus interface pin is set to
high level when used in the I2C bus mode.
Switch a mode to port after making sure that a bus is free.
(10) Arbitration lost detection monitor
Since more than one master device can exist simultaneously on a bus in the I2C bus
mode, a bus arbitration procedure is implemented in order to guarantee the contents of
transferred data.
Data on the SDA line is used for bus arbitration of the I2C bus.
The following shows an example of a bus arbitration procedure when two master
devices exist simultaneously on the bus. Master 1 and Master 2 output the same data
until point “a”. After Master 1 outputs “1” and Master 2, “0”, the SDA line of the bus is
wired AND and the SDA line is pulled down to the low level by Master 2. When the
SCL line of the bus is pulled up at point “b”, the slave device reads data on the SDA line,
that is, data in Master 2. Data transmitted from Master 1 becomes invalid. The state in
Master 1 is called “arbitration lost”. A master device which loses arbitration releases
the SDA pin and the SCL pin in order not to effect data transmitted from other masters
with arbitration. When more than one master sends the same data at the first word,
arbitration occurs continuously after the second word.
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SCL (Bus)
SDA pin (Master 1)
SDA pin becomes “1” after losing arbitration.
SDA pin (Master 2)
SDA (Bus)
b
a
Figure 2.10.9 Arbitration Lost
The TMP88CU74 compares levels of the SDA line of the bus with those of the
TMP88CU74 SDA pin at the rising edge of the SCL line. If the levels are unmatched,
arbitration is lost and the AL (bit 3 in SBISR) is set to “1”.
When the AL is set to “1”, the MST and TRX are reset to “0” and the mode is switched
to a slave receiver mode.
The AL is reset to “0” by writing/reading data to/from the SBIDBR or writing data to
the SBICR2.
SCL pin
1
2
3
4
5
6
7
8
SDA pin
D7A
D6A
D5A
D4A
D3A
D2A
D1A
D0A
SCL pin
1
2
SDA pin
D7B
D6B
9
1
2
3
4 ・・・
D7A’
D6A’
D5A’
D4A’ ・・・
Master
A
Master
B
Fix SDA, SCL pin to high level as losing arbitration.
AL
MST
TRX
Accessed to
SBIDBR or SBICR2
Figure 2.10.10 Example of when TMP88CU74 is a Master B
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(11) Slave address match detection monitor
The AAS (bit 2 in SBISR) is set to “1” in the slave mode, in the address recognition
mode (ALS = 0), or when receiving a slave address with the same value that sets a
GENERAL CALL or I2CAR. When the ALS is “1”, the AAS is set to “1” after receiving
the first 1-word of data. The AAS is cleared to “0” by after writing/reading data to/from
a data buffer register.
(12) GENERAL CALL detection monitor
The AD0 (bit 1 in SBISR) is set to “1” in the slave mode, when all 8-bit data received
immediately after a start condition are “0”. The AD0 is cleared to “0” when a start or
stop condition is detected on the bus.
(13) Last received bit monitor
The SDA value stored at the rising edge of the SCL line is set to the LRB (bit 0 in
SBISR). When the contents of the LRB are read immediately after an INTSBI
interrupt request is generated in the acknowledge mode, and ACK signal is read.
(14) Software Reset Function
Software reset function is used to initialize SBI, when SBI is rocked by external
noise, etc.
SWRST (bit 0 in SBICR) is set to “1”, internal reset signal pulse is generated and
inputted into SBI circuit.
All command registers and status registers are initialized to an initial value.
SWRST is automatically cleared to “0” after initializing SBI circuit.
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2.10.5
Data Transfer in I2C Bus Mode
(1) Device initialization
First, set the ACK in the SBICR1 to “1”, the BC to “000”, and the data length to 8-bit
to count a clock pulse for the acknowledge signal. In addition, set the transmit
frequency to the SCK.
Next, set the slave address to the SA in the I2CAR. Clear the ALS to “0” to set the
addressing format.
After confirming that the serial bus interface pin is high level, for specifying the
default setting to a slave receiver mode, clear “0” to the MST, TRX, and BB in the
SBICR2; “1” to the PIN; “10” to the SBIM; and “0” to bits 1 and 0.
Note:
To initialize the serial bus interface circuit, a constant period that the start conditions
are not generated for any device is required after all devices which are connected to
the bus are initialized. Then, the initialization must be completed during the period.
If not, other devices may start transmitting data before the serial bus interface circuit
has been initialized. Thus, data can not be normally received.
(2) Start condition and slave address generation
Confirm a bus free status (when BB = 0).
Set the ACK to “1” and specify a slave address and a direction bit to be transmitted to
the SBIDBR.
When the BB is “0”, the start condition are generated and the slave address and the
direction bit which are set to the SBIDBR are output on a bus by writing “1” to the MST,
TRX, BB, and PIN. An INTSBI interrupt request occurs at the 9th falling edge of the
SCL clock cycle, and the PIN is cleared to “0”. The SCL pin is pulled down to the low
level while the PIN is “0”. When an interrupt request occurs, the TRX changes by the
hardware according to the direction bit only when an acknowledge signal is returned
from the slave device.
Note 1: The slave address to be output to the SBIDBR must be set after the bus free is
detected by software. If setting of the slave address is executed before detection
bus free, the current output data may be corrupted.
Note 2: The bus free must be confirmed by software within 98.0 μs (the shortest
2
transmitting time according to the I C bus standard) after setting of the slave
address to be output. Only when the bus free is confirmed, set “1” to the MST, TRX,
BB, and PIN to generate the start conditions. If the start conditions are generated
without writing “1” to them, transferring may be executed by other masters between
the time when the slave address to be output to the SBIDBR is written and the time
when “1” is written to the MST, TRX, BB, and PIN in the SBICR2. Thus, the slave
address may be corrupted.
SCL pin
1
2
3
4
5
6
7
8
SDA pin
A6
A5
A4
A3
A2
A1
A0
R/ W
Start condition
Slave address + direction bit
9
Acknowledge
signal from a
slave device
PIN
INTSBI
interrupt
request
Figure 2.10.11 Start Condition Generation and Slave Address Transfer
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(3) 1-word data transfer
Check the MST by the INTSBI interrupt process after a 1-word data transfer is
completed, and determine whether the mode is a master or slave.
a.
When the MST is “1” (Master mode)
Check the TRX and determine whether the mode is a transmitter or receiver.
1.
When the TRX is “1” (Transmitter mode)
Check the LRB. When the LRB is “1”, a receiver does not request data.
Implement the process to generate a stop condition and terminate data transfer.
When the LRB is “0”, the receiver requests new data. When the next
transmitted data is other than 8 bits, set the BC and write the transmitted data to
the SBIDBR after setting ACK to “1”. After writing the data, the PIN becomes “1”,
a serial clock pulse is generated for transferring a new 1-word of data from the
SCL pin, and then the 1-word data is transmitted. After the data is transmitted,
an INTSBI interrupt request occurs. The PIN becomes “0” and the SCL pin is
pulled down to the low level. If the data to be transferred is more than one word in
length, repeat the procedure from the LRB checking above.
Write to SBIDBR
SCL pin
1
2
3
4
5
6
7
8
SDA pin
D7
D6
D5
D4
D3
D2
D1
D0
9
Acknowledge signal
from a receiver
PIN
INTSBI
interrupt request
Figure 2.10.12 Example when BC = “000”, ACK = “1”
2.
When the TRX is “0” (Receiver mode)
When the next transmitted data is other than 8 bits, set the BC again. Set the
ACK to “1” and read the received data from the SBIDBR (data which is read
immediately after a slave address is sent is undefined). After the data is read, the
PIN becomes “1”. The TMP88CU74 outputs a serial clock pulse to the SCL to
transfer new 1-word of data and sets the SDA pin to “0” at the acknowledge signal
timing.
An INTSBI interrupt request occurs and the PIN becomes “0”. The TMP88CU74
outputs a clock pulse for 1-word of data transfer and the acknowledge signal each
time that received data is read from the SBIDBR.
Read SBIDBR
SCL pin
1
2
3
4
5
6
7
8
SDA pin
D7
D6
D5
D4
D3
D2
D1
D0
9
New D7
Acknowledge signal
to a transmitter
PIN
INTSBI
interrupt request
Figure 2.10.13 Example when BC = “000”, ACK = “1”
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In order to terminate transmitting data to a transmitter, clear the ACK to “0”
before reading data which is 1 word before the last data to be received. The last
data does not generate a clock pulse for the acknowledge signal. After the data is
transmitted and an interrupt request has occurred, set the BC to “001” and read
the data. The TMP88CU74 generates a clock pulse for a 1-bit data transfer. Since
the master device is a receiver, the SDA line of the bus keeps the high level. The
transmitter receives the high-level signal as an ACK signal. The receiver
indicates to the transmitter that data transfer is complete.
After 1-bit data is received and an interrupt request has occurred, the
TMP88CU74 generates a stop condition and terminates data transfer.
SCL pin
SDA pin
1
2
3
4
5
6
7
8
D7
D6
D5
D4
D3
D2
D1
D0
1
Acknowledge signal
sent to a transmitter
PIN
INTSBI
interrupt request
“001” → BC,
Read SBIDBR
“0” → ACK,
Read SBIDBR
Figure 2.10.14 Termination of Data Transfer in Master Receiver Mode
b.
When the MST is “0” (Slave mode)
In the slave mode, the TMP88CU74 operates either in normal slave mode or in
slave mode after losing arbitration.
In the slave mode, an INTSBI interrupt request occurs when the TMP88CU74
receives a slave address or a GENERAL CALL from the master device, or when a
GENERAL CALL is received and data transfer is complete after matching a
received slave address. In the master mode, the TMP88CU74 operates in a slave
mode if it is losing arbitration. An INTSBI interrupt request occurs when word
data transfer terminates after losing arbitration. When an INTSBI interrupt
request occurs, the PIN (bit 4 in the SBICR2) is reset, and the SCL pin is pulled
down to the low level. Either reading/writing from/to the SBIDBR or setting the
PIN to “1” releases the SCL pin after taking tLOW time.
Check the AL (bit 3 in the SBISR), the TRX (bit 6 in the SBISR), the AAS (bit 2
in the SBISR), and the AD0 (bit 1 in the SBISR) and implements processes
according to conditions listed in the next table.
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Table 2.10.1 Operation in the Slave Mode
TRX
AL
1
AAS
AD0
Conditions
Process
1
0
The TMP88CU74 loses arbitration when
transmitting a slave address and receives a slave
address of which the value of the direction bit sent
from another master is “1”.
Set the number of bits in 1 word to the
BC and write transmitted data to the
SBIDBR.
1
0
In the slave receiver mode, the TMP88CU74
receives a slave address of which the value of the
direction bit sent from the master is “1”.
1
In the slave transmitter mode, 1-word data is
transmitted.
Check the LRB. If the LRB is set to
“1”, set the PIN to “1” since the
receiver does not request next data.
Then, clear the TRX to “0” release the
bus. If the LRB is cleared to “0”, set
the number of bits in a word to the BC
and write transmitted data to the
SBIDBR since the receiver requests
next data.
The TMP88CU74 loses arbitration when
transmitting a slave address and receives a slave
address or GENERAL CALL of which the value of
the direction bit sent from another master is “0”.
Read the SBIDBR for setting the PIN
to “1” (reading dummy data) or write
“1” to the PIN.
0
0
0
0
1/0
0
0
1
0
1
1/0
0
1/0
0
The TMP88CU74 loses arbitration when
transmitting a slave address or data and terminates
transferring word data.
In the slave receiver mode, the TMP88CU74
receives a slave address or GENERAL CALL of
which the value of the direction bit sent from the
master is “0”.
In the slave receiver mode, the TMP88CU74
terminates receiving of 1-word data.
Set the number of bits in a word to the
BC and read received data from the
SBIDBR.
(4) Stop condition generation
When the BB is “1”, a sequence of generating a stop condition is started by writing
“1” to the MST, TRX, and PIN, and “0” to the BB. Do not modify the contents of the
MST, TRX, BB, PIN until a stop condition is generated on a bus.
“1” →MST
“1” →TRX
“0” →BB
“1” →PIN
Stop condition
SCL pin
SDA pin
PIN
BB (Read)
Figure 2.10.15 Stop Condition Generation
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(5) Restart
Restart is used to change the direction of data transfer between a master device and
a slave device during transferring data. The following explains how to restart when the
TMP88CU74 is in the master mode.
Specify “0” to the MST, TRX, and BB and “1” to the PIN and release the bus. The
SDA pin retains the high level and the SCL pin is released. Since a stop condition is not
generated on a bus, a bus is assumed to be in a busy state from other devices. Check
the BB until it becomes “0” to check that the SCL pin of theTMP88CU74 is released.
Check the LRB until it becomes “1” to check that the SCL line of a bus is not pulled
down to the low level by other devices. After confirming that a bus stays in a free state,
generate a start condition with procedure (2).
In order to meet setup time when restarting, take at least 4.7 [μs] of waiting time by
software from the time of restarting to confirm that the bus is free until the time to
generate the start condition.
“0” → MST
“0” → TRX
“0” → BB
“1” → PIN
“1” → MST
“1” → TRX
“1” → BB
“1” → PIN
4.7 [μs] (Min)
Start condition
SCL (Bus)
SCL pin
SDA (pin)
LRB
BB
PIN
Figure 2.10.16 Timing Diagram when Restarting theTMP88CU74
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2.10.6
Clocked-synchronous 8-Bit SIO Mode Control
The following registers are used to control the serial bus interface (SBI-ver.C) and
monitor the operation status in the clocked-synchronous 8-bit SIO mode.
Serial Bus Interface Control Register 1
7
6
5
SBICR1
(00020H)
SIOS
SIOS
SIOINH
SIOM
SCK
SIO
INH
4
SIOM
3
2
“0”
1
0
(Initial value: 0000 *000)
SCK
0: Stop
1: Start
0: Continue transfer
1: Abort transfer (automatically cleared after abort)
00: 8-bit transmit mode
01: Reserved
10: 8-bit transmit/receive mode
11: 8-bit receive mode
000: fc/25 (390 kHz)
001: fc/26 (195 kHz)
010: fc/27 (97.6 kHz)
011: fc/28 (48.8 kHz)
at fc = 12.5 MHz
100: fc/29 (24.4 kHz)
(Output on SCK pin)
101: fc/210 (12.2 kHz)
11
110: fc/2 (6.1 kHz)
111: External clock (input from SCK pin)
Indicate transfer start/stop
Continue/Abort transfer
Transfer mode select
Serial clock select
Write
only
Note 1:
*: Don’t care
Note 2:
Set the SIOS to “0” when setting the transfer mode or serial clock.
Note 3:
SBICR1 is write-only register, which cannot be used with any of read-modify-write instruction such as bit
manipulation, etc.
Serial Bus Interface Data Buffer Register
7
6
5
SBIDBR
4
3
2
1
0
(00021H)
R/W
Note:
Cannot read the data which was written into SBIDBR, since a write data buffer and a read buffer are
independent in SBIDBR. Therefore, SBIDBR cannot be used with any in read-modify-write instruction such as
bit manipulation, etc.
Serial Bus Interface Control Register 2
7
6
5
SBICR2
(00023H)
“0”
4
3
“1”
2
SBIM
1
0
“0”
“0”
(Initial value: **** 00**)
“0”
“0”
SBIM
00: Port mode (serial bus interface output disable)
Serial bus interface operation 01: Clocked-synchronous 8-bit SIO mode
mode selection
10: I2C bus mode
11: Reserved
Note 1:
*: Don’t care
Note 2:
Switch a mode to port after data transfer is complete.
Note 3:
Write
only
Switch a mode to I2C bus mode or clocked-synchronous 8-bit SIO mode after confirming that input signal via
port is high level.
Note 4:
SBICR2 is write-only register, which cannot be used with any of read-modify-write instruction such as bit
manipulation, etc.
Note 5:
Clear bits 7 to 5 and bits 1 to 0 in SBICR2 to “0”, and set bit 4 to “1”.
Serial Bus Interface Status Register
7
6
5
SBISR
(00023H)
“1”
“1”
SIOF
Serial
transfer
status monitor
SEF
“1”
4
3
2
1
0
“1”
SIOF
SEF
“1”
“1”
operating 0 : Transfer terminated
1 : Transfer in process
0 : Shift operation terminated
Shift operating status monitor
1 : Shift operation in process
Read
only
Figure 2.10.17 Control Register/Data Buffer Register/Status Register in SIO Mode
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(1) Serial clock
a.
Clock source
The SCK(bits 2 to 0 in SBICR1) is used to select the following functions.
1.
Internal clock
In an internal clock mode, any of seven frequencies can be selected. The serial
clock is output to the outside on the SCK0 pin. The SCK0 pin becomes a high
level when data transfer starts. When writing (in the transmit mode) or reading
(in the receive mode) data cannot follow the serial clock rate, an automatic-wait
function is executed to stop the serial clock automatically and hold the next shift
operation until reading or writing is complete.
automatic-wait function
SCK 0 pin output
SO0 pin output
Write transmitted
data
1
2
3
7
8
1
a0
a1
a2 a5
a6
a7
b0
a
b
2
b1 b4
6
7
8
1
2
3
b5
b6
b7
c0
c1
c2
c
Figure 2.10.18 Automatic Wait Function
2.
External clock (SCK = “111”)
An external clock supplied to the SCK0 pin is used as the serial clock. In order
to ensure shift operation, a pulse width of at least 4 machine cycles is required for
both high and low levels in the serial clock. The maximum data transfer frequency
is 390 kHz (fc = 12.5 MHz).
SCK 0 pin
tSCKL tSCKH
tSCKL, tSCKH > 4 tcyc
Note: tcyc = 4/fc (in NORMAL mode, IDLE mode)
Figure 2.10.19 The Maximum Data Transfer Frequency in the External Clock Input
b.
Shift edge
The leading edge is used to transmit data, and the trailing edge is used to
receive data.
1.
Leading edge
Data is shifted on the leading edge of the serial clock (at a falling edge of the
SCK0 pin input/output).
2.
Trailing edge
Data is shifted on the trailing edge of the serial clock (at a rising edge of the
SCK0 pin input/output).
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SCK 0 pin
Bit 0
Bit 1
Bit 2
Bit 3
Bit 4
Bit 5
Bit 6
Bit 7
76543210
*7654321
**765432
***76543
****7654
*****765
******76
*******7
Bit 3
Bit 4
Bit 5
Bit 6
Bit 7
SO0 pin
Shift register
(a) Leading edge
SCK 0 pin
Bit 0
SI0 pin
Shift register
********
Bit 1
0*******
Bit 2
10******
210*****
3210****
(b) Trailing edge
43210***
543210**
6543210*
76543210
*: Don’t care
Figure 2.10.20 Shift Edge
(2) Transfer mode
The SIOM (bits 5 and 4 in SIO1CR) is used to select a transmit, receive, or
transmit/receive mode.
a.
8-bit transmit mode
Set a control register to a transmit mode and write data to the SBIDBR.
After the data is written, set the SIOS to “1” to start data transfer. The
transmitted data is transferred from the SBIDBR to the shift register and output
to the SO0 pin in synchronous with the serial clock, starting from the least
significant bit (LSB). When the data is transferred to the shift register, the
SBIDBR becomes empty. The INTSBI (buffer empty) interrupt request is
generated to request new data.
When the internal clock is used, the serial clock will stop and automatic-wait
function will be initiated if new data is not loaded to the data buffer register after
the specified 8-bit data is transmitted. When new data is written, automatic-wait
function is canceled.
When the external clock is used, data should be written to the SBIDBR before
new data is shifted. The transfer speed is determined by the maximum delay time
between the time when an interrupt request is generated and the time when data
is written to the SBIDBR by the interrupt service program.
When the transmit is started, the same value as the final bit of the last data is
output until the falling edge of the SCK after the SIOF goes “1”.
Transmitting data is ended by cleaning the SIOS to “0” by the buffer empty
interrupt service program or setting the SIOINH to “1”. When the SIOS is cleared,
the transmitted mode ends when all data is output. In order to confirm if data is
surely transmitted by the program, set the SIOF (bit 3 in the SBISR) to be sensed.
The SIOF is cleared to “0” when transmitting is complete. When the SIOINH is
set, transmitting data stops. The SIOF turns “0”.
When the external clock is used, it is also necessary to clear the SIOS to “0”
before new data is shifted; otherwise, dummy data is transmitted and operation
ends.
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Clear SIOS
SIOS
SIOF
SEF
SCK 0 pin (output)
SO0 pin
a0
*
a1
a2
a3
a4
a5
a6
a7
b0
b1
b2
b3
b4
b5
b6
b7
b5
b6
b7
INTSIO interrupt
request
SBIDBR
a
b
(a) Interral clock
Write transmitted data
Clear SIOS
SIOS
SIOF
SEF
SCK 0 pin (Input)
SO0 pin
a0
*
a1
a2
a3
a4
a5
a6
a7
b0
b1
b2
b3
b4
INTSBI interrupt
request
SBIDBR
a
b
Write transmitted data
(b) External clock
Figure 2.10.21 Transfer Mode
Example: SIO0 transfer end command (External clock)
STEST1:
TEST
(SBISR). SEF
JRS
F, STEST1
STEST2:
TEST
(P3). 6
JRS
T, STEST2
LD
(SBICR1), 00000111B
88CU74-99
;
If SEF = 1 then loop
;
If SCK = 0 then loop
;
SIOS ← 0
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TMP88CU74
SCK 0 pin
SIOF
SO0 pin
Bit6
Bit7
tSODH = 3.5/fc [s] (min) (In NORMAL mode, IDLE mode)
Figure 2.10.22 Transmitted Data Hold Time at End of Transmit
b.
8-bit receive mode
Set a control register to a receive mode and the SIOS to “1” for switching to a
receive mode. Data is received from the SI0 pin to the shift register in
synchronous with the serial clock, starting from the least significant bit (LSB).
When the 8-bit data is received, the data is transferred from the shift register to
the SBIDBR. The INTSBI (buffer full) interrupt request is generated to request of
reading the received data. The data is then read from the SBIDBR by the
interrupt service program.
When the internal clock is used, the serial clock will stop and automatic-wait
function will be initiated until the received data is read from the SBIDBR.
When the external clock is used, since shift operation is synchronized with the
clock pulse provided externally, the received data should be read before new data
is transferred to the SBIDBR. If the received data is not read, further data to be
received is canceled. The maximum transfer speed when the external clock is used
is determined by the delay time between the time when an interrupt request is
generated and the time when received data is read.
Receiving data is ended by clearing the SIOS to “0” by the buffer full interrupt
service program or setting the SIOINH to “1”. When the SIOS is cleared, received
data is transferred to the SBIDBR in complete blocks. The received mode ends
when the transfer is complete. In order to confirm if data is surely received by the
program, set the SIOF (bit 3 in SBIDBR) to be sensed. The SIOF is cleared to “0”
when receiving is complete. After confirming that receiving has ended, the last
data is read. When the SIOINH is set, receiving data stops. The SIOF turns “0”
(the received data becomes invalid, therefore no need to read it).
Note:
When the transfer mode is switched, the SBIDBR contents are lost. In case
that the mode needs to be switched, conclude receiving data by clearing the
SIOS to “0”, read the last data, and then switch the mode.
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Clear SIOS
SIOS
SIOF
SEF
SCK 0 pin (output)
a0
SI0 pin
a1
a2
a3
a4
a5
a6
a7
b0
b1
b2
b3
b4
b5
b6
b7
INTSBI interrupt
request
SBIDBR
a
Read received data
b
Read received data
Figure 2.10.23 Receive Mode (Example: Internal Clock)
c.
8-bit transmit/receive mode
Set a control register to a transmit/receive mode and write data to the SBIDBR.
After the data is written, set the SIOS to “1” to start transmitting/receiving. When
transmitting, the data is output from the SO0 pin on the leading edges in
synchronous with the serial clock, starting from the least significant bit (LSB).
When receiving, the data is input to the SI0 pin on the trailing edges of the serial
clock. 8-bit data is transferred from the shift register to the SBIDBR, and the
INTSBI interrupt request occurs. The interrupt service program reads the
received data from the data buffer register and writes data to be transmitted. The
SBIDBR is used for both transmitting and receiving. Transmitted data should
always be written after received data is read.
When the internal clock is used, automatic-wait function is initiated until
received data is read and next data is written.
When the external clock is used, since the shift operation is synchronized with
the serial clock provided externally, received data is read and transmitted data is
written before new shift operation is executed. The maximum transfer speed
when the external clock is used is determined by the delay time between the time
when an interrupt request is generated and the time when received data is read
and transmitted data is written.
When the transmit is started, the same value as the final bit of the last data is
output until the falling edge of the SCK after the SIOF goes “1”.
Transmitting/receiving data is ended by cleaning the SIOS to “0” by the INTSBI
interrupt service program or setting the SIOINH to “1”. When the SIOS is cleared,
received data is transferred to the SBIDBR in complete blocks. The
transmit/receive mode ends when the transfer is complete. In order to confirm if
data is surely transmitted/received by the program, set the SIOF (bit 3 in SBISR)
to be sensed. The SIOF becomes “0” after transmitting/receiving is complete.
When the SIOINH is set, transmitting/receiving data stops. The SIOF turns “0”.
Note:
When the transfer mode is switched, the SBIDBR contents are lost. In case
that the mode needs to be switched, conclude transmitting/receiving data by
clearing the SIOS to “0”, read the last data, and then switch the transfer mode.
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Clear SIOS
SIOS
SIOF
SEF
SCK 0 pin
*
SO0 pin
SI0 pin
a0
a1
a2
a3
a4
a5
a6
a7
b0
b1
b2
b3
b4
b5
b6
b7
c0
c1
c2
c3
c4
c5
c6
c7
d0
d1
d2
d3
d4
d5
d6
d7
INTSBI interrupt
request
a
SBIDBR
c
Write transmitted
data (a)
Read received
data (c)
b
Write transmitted
data (b)
d
Read received
data (d)
Figure 2.10.24 Transmit/Receive Mode (Example: Internal Clock)
SCK 0 pin
SIOF
SO0 pin
Bit 6
Bit 7 in last transmitted word
tSODH = Min 4/fc [s] (In NORMAL mode, IDLE mode)
Figure 2.10.25 Transmitted Data Hold Time at End of Transmit/Receive
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2.11 Serial Interface (SIO1)
The TMP88CU74 has clocked-synchronous 8-bit serial interfaces (SIO1). The serial interface
has an 8-byte transmit and receive data buffer that can automatically and continuously
transfer up to 64 bits of data.
The serial interface is connected to external devices via pins P02 (SO1), P01 (SI1), P00
( SCK1 ) for SIO1. The serial interface pins are also used as port P0. When used as serial
interface pins, the output latches of these pins should be set to “1” and set to input mode by
P0CR. In the transmit mode, pins P01 can be used as normal I/O ports, and in the receive mode,
the pins P02 can be used as normal I/O ports.
2.11.1
Configuration
SIO control/status registers
SIO1CR1/SIO1SR
CPU
SIO1CR2
Transmit and receive data
buffer
8 byte in DBR
Buffer control
circuit
Control Circuit
Shift register
Shift clock
7
6
5
4
3
8-bit transfer
INTSIO1 interrupt request
Serial clock
2
1
0
4-bit transfer
SO1
Serial data output
SI1
Serial data input
SCK1
Serial clock
input/output
Figure 2.11.1 Serial Interface
2.11.2
Control
The serial interface is controlled by SIO1 control registers (SIO1CR1/SIO1CR2). The
serial interface status can be determined by reading SIO1 status register (SIO1SR).
The transmit and receive data buffer is controlled by the BUF (bits 2 to 0 in SIO1CR2).
The data buffer is assigned to addresses 0FF8H to 0FFFH for SIO1 in the DBR area, and
can continuously transfer up to 8 words (bytes or nibbles) at one time. When the specified
number of words has been transferred, a buffer empty (in the transmit mode) or a buffer
full (in the receive mode or transmit/receive mode) interrupt (INTSIO1) is generated.
When the internal clock is used as the serial clock in the 8-bit receive mode and the 8-bit
transmit/receive mode, a fixed interval wait can be applied to the serial clock for each word
transferred. Four different wait times can be selected with WAIT (bits 4 and 3 in
SIO1CR2).
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SIO Interface 1 Control Register 1
7
6
SIO1CR1
(00027H)
SIOS
SIOS
SIOINH
SIOM
5
SIO
INH
4
3
2
1
SIOM
0
SCK
(Initial value: 0000 0000)
Indicate transfer start/stop
0: Stop
1: Start
Continue/Abort transfer
0: Continue transfer
1: Abort transfer (automatically cleared after abort)
Transfer mode select
000: 8-bit transmit mode
010: 4-bit transmit mode
100: 8-bit transmit/receive mode
101: 8-bit receive mode
110: 4-bit receive mode
NORMAL1/2, IDLE1/2 mode
DV7CK = 0
DV7CK = 1
DV1CK = 0 DV1CK = 1 DV1CK = 0 DV1CK = 1
SCK
Serial clock select
Output on SCK 1 pin
000
001
010
fc/213
fc/28
fc/26
011
fc/25
fc/214
fc/29
fc/27
fs/25
fc/28
fc/26
fs/25
fc/29
fc/27
fc/26
fc/25
fc/26
External clock (input from SCK pin)
111
SLOW,
SLEEP
mode
Write
only
fs/25
−
−
−
Note 1: Set SIOS to “0” and SIOINH to “1” when setting the transfer mode or serial clock.
Note 2: SIO1CR1 is write-only registers, which cannot access any of in read-modify-write instruction such as bit operate,
etc.
SIO Interface 1 Control Register 2
SIO1CR2
7
6
(00028H)
5
4
3
2
WAIT
1
BUF
0
(Initial value: ***0 0000)
Always “0” (Except 8 bit transmit/receive modes)
00: Tf = TD (Non-wait)
WAIT
Wait control
01: Tf = 2TD
10: Tf = 4TD
(Wait)
11: Tf = 8TD
Buffer address used
SIO1
000: 1 word transfer
BUF
Number of transfer words
00FF8H
001: 2 words transfer
00FF8 - 00FF9H
010: 3 words transfer
00FF8 - 00FFAH
011: 4 words transfer
00FF8 - 00FFBH
100: 5 words transfer
00FF8 - 00FFCH
101: 6 words transfer
00FF8 - 00FFDH
110: 7 words transfer
00FF8 - 00FFEH
111: 8 words transfer
00FF8 - 00FFFH
Write
only
Figure 2.11.2 SIO Interface 1 Control Registers (1/2)
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Note 1: Tf: frame time, TD: data transfer time
SCK1 pin
TD
Tf
Note 2: The lower 4 bits of each buffer are used during 4-bit transfers. Zeros (0) are stored to the upper 4 bits when
receiving.
Note 3: Transmitting starts at the lowest address. Received data are also stored starting from the lowest address to the
highest address. For example, in the case of SIO, the first buffer address transmitted is 00FF8H.
Note 4: The value to be loaded to BUF is held after transfer is completed.
Note 5: Set the SIOS to “0” when setting the transfer mode or serial clock.
Note 6: *: Don’t care
Note 7: SIO1CR2 is write-only register, which cannot access any of in read-modify-write instruction such as bit operate,
etc.
Figure 2.11.3 SIO Interface 1 Control Registers (2/2)
SIO1SR
(00027H)
7
6
5
4
3
2
1
0
SIOF
SEF
“1”
“1”
“1”
“1”
“1”
“1”
SIOF
SEF
Serial transfer operating
status monitor
0: Transfer terminated
1: Transfer in process
Shift operating status monitor
0: Shift operation terminated
1: Shift operation in process
Read
only
Figure 2.11.4 SIO Interface 1 Status Register
(1) Serial clock
a.
Clock source
SCK (bits 2 to 0 in SIO1CR1) is able to select the following:
1.
Internal clock
Any of four frequencies can be selected. The serial clock is output to the outside
on the SCK1 pin. The SCK1 pin goes high when transfer starts.
When data writing (in the transmit mode) or reading (in the receive mode or the
transmit/receive mode) cannot keep up with the serial clock rate, there is a wait
function that automatically stops the serial clock and holds the next shift
operation until the read/write processing is completed.
Table 2.11.1 Serial Clock Rate
Serial clock
DV7CK = 0
DV1CK = 0
13
fc/2 [Hz]
fc/28
fc/26
fc/25
DV7CK = 1
DV1CK = 1
14
fc/2 [Hz]
fc/29
fc/27
fc/26
DV1CK = 0
5
fs/2 [Hz]
fc/28
fc/26
fc/25
DV1CK = 1
5
fs/2 [Hz]
fc/29
fc/27
fc/26
SLOW,
SLEEP
mode
5
fs/2 [Hz]
―
―
―
Maximum transfer rate
fc = 12.5 MHz
fs = 32.768 KHz
1.50 Kbit/s
48.8
185
390
1 Kbit/s
―
―
―
Note: 1 Kbit = 1024 bits
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Automatically
wait function
SCK1 pin output
a0
SO1 pin output
Written transmit
data to the DBR
a1
a2
a3
b0
a
b1
b
b2
b3
c0
c1
c
Figure 2.11.5 Clock Source (Internal Clock)
2.
External clock
An external clock connected to the SCK1 pin is used as the serial clock. In this
case, the P00 ( SCK1 ) output latch must be set to “1”. To ensure shifting, a pulse
width of at least 4 machine cycles is required. Thus, the maximum transfer speed
is 390 Kbit/s. (at fc = 12.5 MHz).
SCK1 pin input
tSCKL tSCKH
tSCKL, tSCKH > 4tcyc
b.
Note: tcyc = 4/fc (In NORAML1/2, IDLE1/2 modes)
4/fs (In SLOW, SLEEP modes)
Shift edge
The leading edge is used to transmit, and the trailing edge is used to receive.
1.
Leading edge
Transmitted data are shifted on the leading edge of the serial clock (falling edge
of the SCK1 pin input/output).
2.
Trailing edge
Received data are shifted on the trailing edge of the serial clock (rising edge of
the SCK1 pin input/output).
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SCK1 pin
SO1 pin
Bit 0
Bit 1
Bit 2
Bit 3
Shift register
3210
*321
**32
***3
(a) Leading Edge
SCK1 pin
SI1 pin
Bit 0
Shift register
****
Bit 1
0***
Bit 2
10**
Bit 3
210*
(b) Trailing Edge
3210
*: Don’t care
Figure 2.11.6 Shift Edge
(2) Number of bits to transfer
Either 4-bit or 8-bit serial transfer can be selected. When 4-bit serial transfer is
selected, only the lower 4 bits of the transmit/receive data buffer register are used. The
upper 4 bits are cleared to “0” when receiving.
The data is transferred in sequence starting at the least significant bit (LSB).
(3) Number of words to transfer
Up to 8 words consisting of 4 bits of data (4-bit serial transfer) or 8 bits (8-bit serial
transfer) of data can be transferred continuously. The number of words to be
transferred is loaded to BUF in SIOBCR.
An INTSIO interrupt is generated when the specified number of words has been
transferred. If the number of words is to be changed during transfer, the serial
interface must be stopped before making the change.
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SCK1 pin
a0
SO1 pin
a1
a2
a3
INTSIO interrupt
(a) 1 word transmit
SCK1 pin
a0
SO1 pin
a1
a2
a3
b0
b1
b2
b3
c0
c1
c2
c3
c0
c1
c2
c3
INTSIO interrupt
(b) 3 words transmit
SCK1 pin
a0
SI1 pin
a1
a2
a3
b0
b1
b2
b3
INTSIO interrupt
(c) 3 words receive
Figure 2.11.7 Number of Bits to Transfer (Example: 4-Bit Serial Transfer)
(4) Transfer mode
SIOM (bits 5 to 3 in SIO1CR) is used to select the transmit, receive, or
transmit/receive mode.
a.
4-bit and 8-bit transmit modes
In these modes, the SIO1CR1 is set to the transmit mode and then the data to
be transmitted first are written to the data buffer registers (DBR). After the data
are written, the transmission is started by setting SIOS to “1”. The data are then
output sequentially to the SO1 pin in synchronous with the serial clock, starting
with the least significant bit (LSB). As soon as the LSB has been output, the data
are transferred from the data buffer register to the shift register. When the final
data bit has been transferred and the data buffer register is empty, an INTSIO
(buffer empty) interrupt is generated to request the next transmitted data.
When the internal clock is used, the serial clock will stop and an automatic-wait
will be initiated if the next transmitted data are not loaded to the data buffer
register by the time the number of data words specified with the BUF has been
transmitted. Writing even one word of data cancels the automatic-wait; therefore,
when transmitting two or more words, always write the next word before
transmission of the previous word is completed.
Note:
Waits are also canceled by writing to a DBR not being used as a transmit data
buffer register; therefore, during SIO do not use such DBR for other
applications.
When an external clock is used, the data must be written to the data buffer
register before shifting next data. Thus, the transfer speed is determined by the
maximum delay time from the generation of the interrupt request to writing of the
data to the data buffer register by the interrupt service program.
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The transmission is ended by clearing SIOS to “0” at the time that the final bit
of the data being shifted out has been transferred. That the transmission has
ended can be determined from the status of SIOF (bit 7 in SIO1SR) because SIOF
is cleared to “0” when a transfer is completed.
When an external clock is used, it is also necessary to clear SIOS to “0” before
shifting the next data; otherwise, dummy data will be transmitted and the
operation will end.
Clear SIOS
SIOS
SIOF
SEF
SCK1 pin (output)
a0
SO1 pin
a1
a2
a3
a4
a5
a6
a7
b0
b1
b2
b3
b4
b5
b6
b7
b5
b6
b7
INTSIO interrupt
DBR
a
b
(a) Internal clock
Write Write
(b)
(a)
Clear SIOS
SIOS
SIOF
SEF
SCK1 pin (output)
a0
SO1 pin
a1
a2
a3
a4
a5
a6
a7
b0
b1
b2
b3
b4
INTSIO interrupt
DBR
a
Write Write
(a)
(b)
b
(b) External clock
Figure 2.11.8 Transfer Mode (Example: 8-Bit, 1 Word Transfer)
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SCK1 pin
SIOF
SO1 pin
Bit7
tSODH = 3.5/fc [s] (min) (In the NORMAL1/2, IDLE1/2 modes)
= 3.5/fs [s] (min) (In the SLOW, SLEEP modes)
Figure 2.11.9 Transmitted Data Hold Time at End of Transmit
b.
4-bit and 8-bit receive modes
After setting the control registers to the receive mode, set SIOS to “1” to enable
receiving. The data are then transferred to the shift register via the SI pin in
synchronous with the serial clock. When one word of data has been received, it is
transferred from the shift register to the data buffer register (DBR). When the
number of words specified with the BUF has been received, an INTSIO (buffer
full) interrupt is generated to request that these data be read out. The data are
then read from the data buffer registers by the interrupt service program.
When the internal clock is used, and the previous data are not read from the
data buffer register before the next data are received, the serial clock will stop and
an automatic-wait will be initiated until the data are read. A wait will not be
initiated if even one data word has been read.
Note:
Waits are also canceled by reading a DBR not being used as a received data
buffer register is read; therefore, during SIO do not use such DBR for other
applications.
When an external clock is used, the shift operation is synchronized with the
external clock; therefore, the previous data are read before the next data are
transferred to the data buffer register. If the previous data have not been read, the
next data will not be transferred to the data buffer register and the receiving of
any more data will be canceled. When an external clock is used, the maximum
transfer speed is determined by the delay between the time when the interrupt
request is generated and when the data received have been read.
Clear SIOS to “0” to end receiving. When SIOS is cleared, the current data are
transferred to the buffer in 4-bit or 8-bit blocks. The receiving mode ends when the
transfer is completed. SIOF is cleared to “0” when receiving is ended and thus can
be sensed by program to confirm that receiving has ended.
Note:
The buffer contents are lost when the transfer mode is switched. If it should
become necessary to switch the transfer mode, end receiving by clearing
SIOS to “0”, read the last data and then switch the transfer mode.
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Clear SIOS
SIOS
SIOF
SEF
SCK1 pin (output)
a0
SI1 pin input
a1
a2
a3
a4
a5
a6
a7
b0
b1
b2
b3
b4
b5
b6
b7
INTSIO interrupt
DBR
a
b
Read out
Read out
Figure 2.11.10 Receive Mode (Example: 8-Bit, 1 Word, Internal Clock)
c.
8-bit transmit/receive mode
After setting the control registers to the 8-bit transmit/receive mode, write the
data to be transmitted first to the data buffer registers (DBR). After that, enable
transceiving by setting SIOS to “1”. When transmitting, the data are output from
the SO1 pin at leading edges of the serial clock. When receiving, the data are
input to the SI1 pin at the trailing edges of the serial clock. 8-bit data are
transferred from the shift register to the data buffer register. An INTSIO
interrupt is generated when the number of data words specified with the BUF has
been transferred. The interrupt service program reads the received data from the
data buffer register and then writes the data to be transmitted. The data buffer
register is used for both transmitting and receiving; therefore, always write the
data to be transmitted after reading the received data.
When the internal clock is used, a wait is initiated until the received data are
read and the next data are written.
Note:
Waits are also canceled by reading a DBR not being used as a received data
buffer register is read; therefore, during SIO do not use such DBR for other
applications.
When an external clock is used, the shift operation is synchronized with the
external clock; therefore, it is necessary to read the received data and write the
data to be transmitted next before starting the next shift operation. When an
external clock is used, the transfer speed is determined by the maximum delay
between generation of an interrupt request and the received data are read and the
data to be transmitted next are written.
Clear SIOS to “0” to enable the transmit mode. When SIOS is cleared, the
current data are transferred to the data buffer register in 8-bit blocks. The
transmit mode ends when the transfer is completed. SIOF is cleared to “0” when
receiving is ended and thus can be sensed by program to confirm that receiving
has ended.
Note:
The buffer contents are lost when the transfer mode is switched. If it should
become necessary to switch the transfer mode, end receiving by clearing
SIOS to “0”, read the last data and then switch the transfer mode.
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Clear SIOS
SIOS
SIOF
SEF
SCK1 pin output
SO1 pin
a0
a1
a2
a3
a4
a5
a6
a7
b0
b1
b2
b3
b4
b5
b6
b7
SI1 pin
c0
c1
c2
c3
c4
c5
c6
c7
d0
d1
d2
d3
d4
d5
d6
d7
INTSIO interrupt
DBR
c
a
Write (a)
b
Read out (c) Write (b)
d
Read out (d)
Figure 2.11.11 Transmit/Receive Mode (Example: 8-Bit, 1 Word, Internal Clock)
SCK1 pin
SIOF
SO1 pin
Bit6
Bit7
tSODH
tSODH = 4/fc [s] (min) (In the NORMAL1/2, IDLE1/2 modes)
= 4/fs [s] (min) (In the SLOW, SLEEPmodes)
Figure 2.11.12 Transmitted Data Hold Time at End of Transmit/Receive
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2.12 8-Bit AD Converter (ADC)
The TMP88CU74 each have an 8-channel multiplexed-input 12-bit successive approximate
type AD converter with sample and hold.
2.12.1
Configuration
Ladder resistors
R/2
R
R
R/2
VAREF
VASS
STOP
AINDS
Tap decoder
Analog input
multiplexer
AIN0
A
AIN1
to
AIN10
B
to
K
to
Sample and hold
Reference
voltage
Y
8
Analog
comparator
L
AIN11
Sampling
clock
Successive approximate circuit
EN
Shift clock
EN S
AINDS
12
Control circuit
8
SAIN
ADS
EOCF
4
P4CR, P5CR
ADCCR
ADCDR
P4, P5 input/output control register
AD converter control register
AD conversion result register
Figure 2.12.1 AD Converter
2.12.2
Control
The AD converter is controlled by the AD converter control register (ADCCR).
The operating state of the AD converter is confirmed by reading EOCF in ADCCR. The
AD conversion value is confirmed by reading the contents of AD conversion value registers.
AD Conversion Result Register
7
6
ADCDR
5
4
3
2
(0000FH)
1
0
Read only
Figure 2.12.2 AD Conversion Result Register
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AD Converter Control Register
7
6
ADCCR
(0000EH) EOCF
SAIN
ADS
5
4
ACK
AINDS
Analog input selection
3
2
1
SAIN
0000: AIN0 select
0001: AIN1 select
0010: AIN2 select
0011: AIN3 select
0100: AIN4 select
0101: AIN5 select
0110: AIN6 select
0111: AIN7 select
0
(Initial value: 0000 0000)
1000: AIN8 select
1001: AIN9 select
1010: AIN10 select
1011: AIN11 select
1100: Reserved
1101: Reserved
1110: Reserved
1111: Reserved
Analog input control
0: Enable
1: Disable
ACK
Conversion time selection
0: 184/fc [s]: 23 μs (fc = 8 MHz)
1: 736/fc [s]: 59 μs (fc = 12.5 MHz)
ADS
AD conversion start
0: ⎯
1: AD conversion start
End of AD conversion flag
0: Under conversion or Before conversion
1: End of conversion
AINDS
EOCF
R/W
Read
only
Note 1: Select analog input when AD converter stops.
Note 2: The ADS is automatically cleared to “0” after starting conversion.
Note 3: The EOCF is cleared to “0” when reading the ADCDR.
Note 4: The EOCF is read-only.
Note 5: (ACK = “0” at fc ≤ 8 MHz)
Note 6: When STOP or SLOW mode is activated, the AD control registers are initialized. After NORMAL mode is
resumed, set both the AD control registers again if necessary.
Figure 2.12.3 AD Converter Control Register and AD Conversion Result Register
2.12.3
Operation
Analog reference voltage on high side is applied to the VAREF pin ; on the low side, to the
VASS pin. The reference voltage between VAREF and VASS is divided a ladder resistor
and compared with the analog voltage input for AD conversion.
(1) Start of AD conversion
First, set the corressponding P4CR and P5CR bit to “0” for analog input. Clear the
AINDS (bit 4 in ADCCR) to “0” and select one of twelve analog input AIN11-AIN0 with
the SAIN (bits 3 to 0 in ADCCR).
Note:
The pin that is not used as an analog input can be used as regular input/output pins.
During conversion, do not perform output instruction to maintain a precision for all of
the pins.
AD conversion is started by setting the ADS (bit 6 in ADCCR) to “1”.
Conversion is accomplished in 59 machine cycles (184/fc [s]).
The EOCF (bit 7 in ADCCR) is set to “1” at end of conversion.
When setting the ADS to “1” under AD conversion, the AD converter circuit is
initialized and the AD conversion try again from start.
The sampling of the analog input voltage is excuted at 4 machine cycles after setting
the ADS to “1”.
Note:
The circuit of sample and hold is included in a capacitor of (12 pF (typ.)) through a
register (5 kΩ (typ.)).
Therefore, until 4 machine cycles is over, this capacitor must be charged.
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(2) Reading of AD conversion result
After the end of conversion, read the conversion result from the ADCDR.
The EOCF is automatically cleared to “0” when reading the ADCDR.
(3) AD conversion in STOP mode
When the MCU places in the STOP mode during the AD conversion, the conversion
is terminated and the ADCDR contents become indefinite.
However, if the STOP mode is started after the end of conversion (EOCF = 1), the
ADCDR contents are held.
ADS
ADCDR
Invalid
Result
Invalid
Invalid
Conversion time
736/fc [s]
Result
Conversion time
736/fc [s]
Start
Start
Read
Read
Start
EOCF
Figure 2.12.4 AD Conversion Timing Chart (ACK = 1)
Example:
SLOOP:
; AIN SELECT
LD
(ADCCR), 00100100B
; AD CONVERT START
SET
(ADCCR). 6
TEST
(ADCCR). 7
JRS
T, SLOOP
; RESULT DATA READ
LD
(9EH), (ADCDR)
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;
Selects AIN4, ACK = 1
;
;
ADS = 1
EOCF = 1 ?
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FFH
Conversion result
FEH
FDH
03H
02H
01H
0
1
2
3
253
254
255
256
×
VAREF − VASS
256
Analog input voltage
Figure 2.12.5 Analog Input Voltage vs AD Conversion Result (typ.)
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2.13 Vacuum Fluorescent Tube (VFT) Driver Circuit
The TMP88CU74 features built-in high-breakdown voltage output buffers for directly driving
fluorescent tubes, and a display control circuit used to automatically transfer display data to
the output port.
The segment and the digit, as it is the VFT drive circuit which included in the usual products,
are not allocated. The segment and the digit can be freely allocated in the timing (T0 to T15)
which is specified according to the display tube types and the layout.
2.13.1
Functions
(1) 37 high-breakdown voltage output buffers built-in.
•
Large current output pin (typ. 20 mA) 37 (V0 to V36)
There is also the VKK pin used for the VFT drive power supply.
(2) The dynamic lighting system makes it possible to select 1 to 16 digits (T0 to T15) by
program.
(3) Pins not used for VFT driver can be used as general-purpose ports.
•
Pins can be selected using the VSEL (bits 4 to 0) in VFT control register1 bit by bit.
(4) Display data (112 bytes in DBR) are automatically transferred to the VFT output pin.
(5) Brightness level can be adjusted in 8 steps using the dimmer function.
(6) Table 2.13.1 shown in setting of display time.
Table 2.13.1 Setting of Display Time
DV1CK = 0 [s] DV1CK = 1 [s]
210/fc
211/fc
212/fc
213/fc
210/fc
211/fc
212/fc
213/fc
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2.13.2
Configuration
Internal data bus
Display control register 1
Display control register 2
Display data memory
(112 bytes in DBR)
fc
VFT timing generator
T0 to T15
Output data latch
High-breakdown voltage output
V0
V1
V2
V3
V4
V5
V34 V35 V36
Figure 2.13.1 Vacuum Fluorescent Tube (VFT) Driver Circuit
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2.13.3
Control
The VFT driver circuit is controlled by the VFT control registers (VFTCR1, VFTCR2).
Reading VFTSR determines the VFT operating status.
Switching the mode from NORMAL1/2 to SLOW or STOP puts the VFT driver circuit
into blanking state, and sets segment outputs and digit outputs are cleared to “0”. Thus,
ports P6 to P9, and PD function as general-purpose output ports with pull-down.
VFT control register 1
VFTCR1
7
BLK
(00029H)
BLK
6
5
4
3
2
VSEL
SDT
VFT display control
SDT
Display time select (tdisp)
(Display time of 1 digit)
VSEL
Automatic display select
(When using VFT driver
(automatic display), V31 to V0
are only used to output VFT.)
Pins which are not selected by
the output pins other than the
above-mentioned pins can be
used as general-purpose
input/output pins.
(When using as a
general-purpose input/output
pin, the display data which
corresponds to the pin must
be set to “0”)
1
0
(Initial value: 0000 0000)
0: Display enable
1: Disable
DV1CK = 0 [s]
DV1CK = 1 [s]
210/fc
211/fc
212/fc
213/fc
210/fc
211/fc
212/fc
213/fc
00
01
10
11
00000: 32 (V31 to V0)
00001: 33 (V32 to V0)
00010: 34 (V33 to V0)
00011: 35 (V34 to V0)
00100: 36 (V35 to V0)
00101: 37 (V36 to V0)
Write
only
Note 1: fc: High frequency clock
Note 2: VFTCR1 is write-only register, which cannot use any of in read-modify-write instruction such as bit operate, etc.
Figure 2.13.2 VFT Control Register 1
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VFT control register 2
7
VFTCR2
6
(0002AH)
5
4
3
2
DIM
DIM
STA
1
0
(Initial value: 000* 0000)
STA
Dimmer time select
000: (15/16) × tdisp (s)
001: (14/16) × tdisp (s)
010: (12/16) × tdisp (s)
011: (10/16) × tdisp (s)
100: (8/16) × tdisp (s)
101: (6/16) × tdisp (s)
110: (4/16) × tdisp (s)
111: (2/16) × tdisp (s)
Number of state (display)
0000: 1 display mode (T0)
0001: 2 display mode (T1 to T0)
0010: 3 display mode (T2 to T0)
0011: 4 display mode (T3 to T0)
0100: 5 display mode (T4 to T0)
0101: 6 display mode (T5 to T0)
0110: 7 display mode (T6 to T0)
0111: 8 display mode (T7 to T0)
1000: 9 display mode (T8 to T0)
1001: 10 display mode (T9 to T0)
1010: 11 display mode (T10 to T0)
1011: 12 display mode (T11 to T0)
1100: 13 display mode (T12 to T0)
1101: 14 display mode (T13 to T0)
1110: 15 display mode (T14 to T0)
1111: 16 display mode (T15 to T0)
Write
only
Note 1: VFTCR2 is write-only register, which cannot use any of in read-modify-write instruction such as bit operate, etc.
Note 2: Even if a number of the display digit is set a pin which is equal to the digit dose not output.
It is necessary to write data to the data buffer which corresponds to the digit according to the display timing (T0
to T15).
Note 3: *: Don’t care
VFTSR
(00029H)
7
6
5
4
3
2
1
0
WAIT
WAIT
VFT operational status
monitor
0: VFT display in operation
1: VFT display operation disabled
Read
only
Figure 2.13.3 VFT Control Register 2, VFT Status Register
(1) Setting of display mode
VFT display mode is set by VFT control register 1 (VFTCR1) and VFT control
register 2 (VFTCR2). VFT control register 1 (VFTCR1) sets 1 display time (tdisp) and
the number of display lines (VSEL), and VFT control register 2 (VFTCR2) sets dimmer
timer (DIM) and state (STA). (BLK of VFTCR1 must be set to “1”.) The segments and
the digits are not fixed, so that they can be freely allocated. However the number of
states must be specified according to the number of digits of VFT which you use.
(See Display operation in section 2.13.4 for display timing and data setting
procedures.)
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(2) Display data setting
Data are converted into VFT display data by instructions. The converted data stored
in the display data buffer (addresses 00F80 to 00FCF in DBR) are automatically
transferred to the VFT driver circuit, then transferred to the high-breakdown voltage
output buffer. Thus, to change the display pattern, just change the data in the display
data buffer.
Bits in the VFT segment (dot) and display data area correspond one to one. When
data are set to 1, the segments corresponding to the bits light. The display data buffer
is assigned to the DBR area shown in Figure 2.13.4. (The display data buffer can not be
used as data memory)
Bit
Segment
0 to 7
0 to 7
0 to 7
0 to 7
0 to 4
00F80H
00F90H
00FA0H
00FB0H
00FC0H
Timing
T0
00F81H
00F91H
00FA1H
00FB1H
00FC1H
T1
00F82H
00F92H
00FA2H
00FB2H
00FC2H
T2
00F83H
00F93H
00FA3H
00FB3H
00FC3H
T3
00F84H
00F94H
00FA4H
00FB4H
00FC4H
T4
00F85H
00F95H
00FA5H
00FB5H
00FC5H
T5
00F86H
00F96H
00FA6H
00FB6H
00FC6H
T6
00F87H
00F97H
00FA7H
00FB7H
00FC7H
T7
00F88H
00F98H
00FA8H
00FB8H
00FC8H
T8
00F89H
00F99H
00FA9H
00FB9H
00FC9H
T9
00F8AH
00F9AH
00FAAH
00FBAH
00FCAH
T10
00F8BH
00F9BH
00FABH
00FBBH
00FCBH
T11
00F8CH
00F9CH
00FACH
00FBCH
00FCCH
T12
00F8DH
00F9DH
00FADH
00FBDH
00FCDH
T13
00F8EH
00F9EH
00FAEH
00FBEH
00FCEH
T14
00F8FH
00F9FH
00FAFH
00FBFH
00FCFH
T15
V0 to V7
V8 to V15
V16 to V23
V24 to V31
V32 to V36
Note: Writing “0” in 7 to 5 bit of address 00FC0H to 00FCFH in DBR.
Figure 2.13.4 VFT Display Data Buffer Memory (DBR)
2.13.4
Display Operation
As the above-mentioned, the segment and the digit are not allocated. After setting of the
display timing for the number of digits according to the using VFT and storing the segment
and digit data according to the respective timings, clearing BLK in VFTCR1 to 0 starts VFT
display.
Figure 2.13.5 shows the VFT drive pulse and Figure 2.13.6, Figure 2.13.7 show the
display operation.
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Dimmer time (DIM)
T15
T14
T13
T0
SEG/DEG
One display time (tdisp)
Figure 2.13.5 VFT Drive Waveform and Display Timing
2.13.5
Example of Display Operation
(1) For Conventional type VFT
V0
V1
V2
V3
V4
V5
V6
V7
V8
V9
SEG
SEG
SEG
SEG
SEG
SEG
T
9 8 7 6 5 4 3 2 1 0
Address
When using the conventional type VFT, the output timing of the digits is specified to
output 1 digit for 1 timing. Data must be set to output the pins which are specified to
the digit in sequence. The following figure shows a data allocation of the display data
buffer (DBR) and the output timing when VFT of 10 digits is used and V0 to V9 pins
are allocated as the digit outputs. (When data is first written by the data buffer which
corresponds to the digit pin, it is unnecessary to rewrite the data later.)
0
F
9
9
0
F
9
8
LSB
MSB
LSB
MSB
0
F
8
7
0
F
8
6
0
F
8
5
0
F
8
4
0
F
8
3
0
F
8
2
0
F
8
1
0
F
8
0
0
0
0
0
0
0
0
1
0
0
0
0
0
0
1
0
0
0
0
0
0
1
0
0
0
0
0
0
1
0
0
0
0
0
0
1
0
0
0
0
0
0
1
0
0
0
0
0
0
1
0
0
0
0
0
0
1
0
0
0
0
0
0
0
0 1
1 0
*
*
*
*
*
*
T9
T8
T7
T6
T5
T4
T3
T2
T1
T0
G0
G1
G2
G3
G4
G5
G6
G7
G8
G9
*
*
*
*
*
*
SEG (Write change by display data)
Figure 2.13.6 Example of Conventional Type VFT Driver Pulse
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(2) For Grid scan type VFT
When using the grid scan type VFT, two or more grids must be simultaneously
selected to turn the display pattern which contains two or more grids on. Additionally,
the timing and the data must be determined to set the grid scan mode as follows.
When the display pattern which is fully set in the respective grids is turned on,
only the grids which correspond as ever must be scanned in sequence to turn on
the display pattern. (timing of T8 to T3 in the following figure)
•
When the display pattern which contains two or more grids is turned on, two or
more corresponding grids are simultaneously selected to turn on the display
pattern. (timing of T2 to T0 in the following figure)
T
8 7 6 5 4 3 2 1 0
Address
V0
V1
V2
V3
V4
V5
−
−
•
0
F
8
8
0
F
8
7
0
F
8
6
0
F
8
5
0
F
8
4
0
F
8
3
0
F
8
2
0
F
8
1
0
F
8
0
1
0
0
0
0
0
0
1
0
0
0
0
0
0
1
0
0
0
0
0
0
1
0
0
0
0
0
0
1
0
0
0
0
0
0
1
1
1
0
0
0
0
0
0
0
1
1
1
1
1
1
1
1
1
LSB
T8
T7
T6
T5
T4
T3
T2
T1
T0
G0
G1
G2
G3
G4
G5
MSB
SEG (a to g (Dig 1 to 6))
S1
S2
S3
S4
Figure 2.13.7 Grid Scan Type Display Vacuum Fluorescent Tube Ware
2.13.6
Port Function
(1) High-breakdown voltage buffer
To drive fluorescent display tube, clears the port output latch to “0”. The port output
latch is initialized to 0 at reset.
It is recommended that ports P5, P6, P7, P8 and P9 should be used as VFT driver
output. Precaution for using as general-purpose I/O pins are follows.
When not using a pin which is pulled down to pin VKK (RK = typ. 80 kΩ), it must be
set to open. It is necessary to clear the port output latch and the data buffer memory
(DBR) to “0”.
Ports P6 to P9
Note:
1.
When a part of P6 to P9 is used as the input/output pin (VFT driver in
operation), the data buffer memory (DBR) of the segment which is also used as the
input/output pin must be cleared to “0”.
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2.
Port PD
VFT output and usual input/output are controlled by VSEL of VFT control
register in bits. When a pin which is pulled down to pin VKK is used as usual
output or input, the following cautions are required.
(a) When outputting
When level “L” is output, a port which is pulled down to pin VKK is pin VKK
voltage. Such processes as clamping with the diode as shown in figure 2.13.8. (a)
are necessary to prevent pin VKK voltage applying to the external circuit.
(b) When inputting
When the external data is input, the port output latch is cleared to “0”.
The input threshold is the same as that of the other usual input/output port.
However it is necessary to drive RK (typ. 80 kΩ) sufficiently because of pulled
down to pin VKK.
VDD
VDD
R
R
RK
RK
VKK
VKK
R1
R1
(b) At input
(a) At output
Figure 2.13.8 External Circuit Interface
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Input/Output Circuitry
(1) Control pins
The input/output circuitries of the TMP88CU74 control pins are shown below.
Control Pin
I/O
Circuitry
Remarks
Osc. enable
XIN
XOUT
Input
Output
fc
VDD
VDD
Rf
RO
XIN
XOUT
Osc. enable
XTIN
XTOUT
Input
Output
fs
VDD
VDD
Rf
RO
XTIN
I/O
Resonator connecting pins
(low-frequency)
Rf = 6 MΩ (typ.)
RO = 220 kΩ (typ.)
XTOUT
R
RESET
Resonator connecting pins
(high-frequency)
Rf = 1.2 MΩ (typ.)
VDD
RIN
Hysteresis input
RIN = 220 kΩ (typ.)
R = 1 kΩ (typ.)
Address-trap-reset
Watchdog-timer-reset
System-clock-reset
R
STOP / INT5
Input
Hysteresis input
R = 1 kΩ (typ.)
P20
STOP / INT5
VDD
R
TEST
Input
RIN
Note:
Pull-down resistor
RIN = 70 kΩ (typ.)
R = 1 kΩ (typ.)
The TEST pin of the TMP88PU74 does not have a pull-down resistor. Fix the test pin at
low-level.
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(2) – 1.
Port
Input/Output ports
I/O
Input/Output Circuitry
Initial “High-Z”
P00
P01
P1
I/O
VDD
Disable
I/O
Tri-state I/O
Hysteresis input
R = 1 kΩ (typ.)
R
VDD
Initial “High-Z”
P02
to
P07
Remarks
Disable
Tri-state I/O
R = 1 kΩ (typ.)
R
Initial “High-Z”
P2
I/O
R
VDD
Initial “High-Z”
Open-drain
P3
I/O
Disable
R
I/O
Disable
R
Tri-state I/O
R = 1 kΩ (typ.)
VDD
Initial “High-Z”
RK
P6
P7
P8
P9
Tri-state I/O
Hysteresis input
Programmable･Open-drain
R = 1 kΩ (typ.)
VDD
Initial “High-Z”
P4
P5
Sink open drain output
Hysteresis input
R = 1 kΩ
R
VKK
I/O
Source open drain I/O
High-breakdown voltage
RK = 80 kΩ (typ.)
R = 1 kΩ (typ.)
R1 = 200 kΩ (typ.)
R1
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(2) – 2. Input/Output ports
Port
I/O
Input/Output Circuitry
Initial “High-Z”
VDD
RK
PD
I/O
Remarks
R
VKK
Source open drain I/O
High-breakdown voltage
RK = 80 kΩ (typ.)
R = 1 kΩ (typ.)
R1 = 200 kΩ (typ.)
R1
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Electrical Characteristics
Absolute Maximum Ratings
Parameter
(VSS = 0 V)
Symbol
Pins
Ratings
Supply Voltage
VDD
−0.3 to 6.5
Input Voltage
VIN
−0.3 to VDD + 0.3
Output Voltage
Output Current
(Per 1 pin)
Output Current (Total)
Power Dissipation
[Topr = 25°C]
Unit
V
VOUT1
P2, P3 (at open-drain)
−0.3 to VDD + 0.3
VOUT2
P6, P7, P8, P9, PD
VDD − 40 to VDD + 0.3
IOUT1
P0, P1, P2, P3, P4, P5 Ports
3.2
IOUT2
P6, P7, P8, P9, PD Ports
−25
ΣIOUT1
P0, P1, P3, P4, P5 Ports
−40
ΣIOUT2
P0, P1, P2, P3, P4, P5 Ports
120
ΣIOUT3
P6, P7, P8, P9, PD Ports
−160
PD
(Note 2)
1200
Soldering Temperature
(time)
Tsld
260 (10 s)
Storage Temperature
Tstg
−55 to + 125
Operating Temperature
Topr
−30 to + 70
mA
mW
°C
Note 1: The absolute maximum ratings are rated values which must not be exceeded during operation, even
for an instant. Any one of the ratings must not be exceeded. If any absolute maximum rating is
exceeded, a device may break down or its performance may be degraded, causing it to catch fire or
explode resulting in injury to the user. Thus, when designing products which include this device, ensure
that no absolute maximum rating value will ever be exceeded.
Note 2: Power Dissipation (PD); For PD, it is necessary to decrease 14.3 mw/°C.
Recommended Operating Conditions
Parameter
Supply Voltage
Symbol
(VSS = 0 V, Topr = −30 to 70°C)
Pins
VDD
Conditions
fc =
NORMAL1, 2 modes
12.5 MHz
IDLE1, 2
modes
fs =
SLOW
modes
32.768 KHz SLEEP
STOP
Input High Voltage
VIH1
Except hysteresis input
VIH2
Hysteresis input
VIL1
Except hysteresis input
VIL2
Hysteresis input
fc
modes
VDD ≥ 4.5 V
VDD ≥ 4.5 V
XIN, XOUT
XTIN, XTOUT
Max
Unit
4.5
2.7
5.5
2.0
VDD × 0.70
VDD × 0.75
V
VDD
VDD × 0.90
VDD × 0.30
0
VDD < 4.5 V
VIL3
Clock Frequency
modes
VDD < 4.5 V
VIH3
Input Low Voltage
Min
VDD × 0.25
VDD × 0.10
VDD = 4.5 to 5.5 V (Note 2)
8
12.5
MHz
VDD = 2.7 to 5.5 V
30.0
34.0
kHz
Note 1: The recommended operating conditions for a device are operating conditions under which it can be
guaranteed that the device will operate as specified. If the device is used under operating conditions
other than the recommended operating conditions (Supply voltage, Operating temperature range,
Specified AC/DC values etc.), malfunction may occur. Thus, when designing products which include
this device, ensure that the recommended operating conditions for the device are always adhered to.
Note 2: Clock frequency fc: Supply voltage range is specified in NORMAL 1/2 mode and IDLE 1/2 mode.
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How to Calculate Power Consumption.
With the TMP88CU74, a pull-down resistor (RK = 80 kΩ typ.) can be built into a VFT driver
using mask option (port by port). The share of VFT driver loss (VFT driver output loss + pull-down
resistor (RK) loss) in power consumption Pmax is high. When using a fluorescent display tube with
a large number of segments, the maximum power consumption PD must not be exceeded.
Power consumption Pmax = operating power consumption + normal output port loss + VFT
driver loss
Where,
1.
Operating power consumption: VDD × IDD
2.
Normal power consumption: ΣIOUT2 × 0.4
3.
VFT driver loss: VFT driver output loss + pull-down resistor (RK) loss
Example:
When Ta = 10 to 50°C and a fluorescent display tube with segment output = 3 mA, digit
output = 15 mA, Vxx = −25 V is used.
Operating conditions: VDD = 5 V±10%, fc = 12.5 MHz, VFT dimmer time (DIM) = (14/16) ×
tseg:
Power consumption Pmax = (1) + (2) + (3)
Where, segments pin = X grid pin = Y, Y = 2
1.
Operating power consumption: VDD × IDD = 5.5 V × 20 mA = 110 mW
2.
Normal output port loss:
3.
VFT driver loss: segment pin = 3 mA × 2 V × number of segmentsX = 6 mW × X × number of
gridsY
ΣIOUT2 × 0.4 V = 120 mA × 0.4 V = 48 mW
digit pin =
15 mA × 2 V × 14/16 (DIM) = 52.5 mW
RK loss =
(5.5 + 25 V)2/50 kΩ × (number of segments X + number of
digits Y) = 18.605 mW × (X + 2)
Therefore, Pmax = 110 mW + 48 mW + 6 mW × X + 52.5 mW + 18.605 mW × (X + 2)
= 253.71 mW + 24.605 X
Maximum power consumption PD when Ta = 50°C is determined by the following equation:
> Pmax
PD
842.5 mW
> 253.71 + 24.605 X
23.9
>X
Thus, a fluorescent display tube with less than 23 segments can be used. If a fluorescent
display tube with 23 segments or more is used, either a pull-down resistor must be attached
externally , or the number of segments to be lit must be kept to less than 23 by software.
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DC Characteristics
Parameter
Hysteresis Voltage
Input Current
(VSS = 0 V, Topr = −30 to 70°C)
Symbol
Pins
VHS
Hysteresis input
IIN1
TEST
IIN2
IIN3
Conditions
Min
VDD = 5.5 V
Open drain ports,
Tri-state ports
RESET , STOP
VIN = 5.5 V/0 V
Typ.
Max
Unit
0.9
⎯
V
⎯
⎯
±2
μA
100
220
450
50
80
110
Input Resistance
RIN3
RESET
Pull-down Resistance
RK
Source open drain ports
VDD = 5.5 V, VKK = −30 V
ILO1
Sink open drain ports
VDD = 5.5 V, VOUT = 5.5 V
⎯
⎯
2
ILO2
Source open drain ports
VDD = 5.5 V, VOUT = −32 V
⎯
⎯
−2
ILO3
Tri-state ports
⎯
⎯
2
Output High Voltage
VOH2
Tri-state ports
VDD = 4.5 V, IOH = −0.7 mA
4.1
⎯
⎯
Output Low Voltage
VOL
Except XOUT
VDD = 4.5 V, IOL = 1.6 mA
⎯
⎯
0.4
Output High current
IOH
P6, P7, P8, P9, PD Port
VDD = 4.5 V, VOH = 2.4 V
⎯
−20
⎯
⎯
18
26
Output Leakage
Current
VDD = 5.5 V,
VOUT = 5.5 V/0 V
Supply Current in
NORMAL 1, 2 modes
VDD = 5.5 V
Supply Current in
IDLE 1, 2 modes
fc = 12.5 MHz
fs = 32.768 kHz
⎯
5.5
8.5
VDD = 3.0 V
⎯
30
60
⎯
15
30
⎯
0.5
10
Supply Current in
SLOW mode
VIN = 5.3 V/0.2 V
IDD
kΩ
μA
V
mA
VIN = 2.8 V/0.2 V
Supply Current in
SLEEP mode
fs = 32.768 kHz
VDD = 5.5 V
Supply Current in
STOP mode
VIN = 5.3 V/0.2 V
μA
Note 1: Typical values show those at Topr = 25°C, VDD = 5 V.
Note 2: Input Current IIN1,IIN3; The current through resistor is not included, when the input resistor
(pull-up/pull-down) is contained.
AD Conversion Characteristics
Parameter
Analog Reference Voltage
Symbol
VAREF
VAIN
Analog Supply Current
IREF
Zero Point Error
Full Scale Error
Total Error
Note:
Conditions
Min
Typ.
Max
⎯
VDD
VASS
⎯
VAREF
4.5
VAREF = 5.5 V, VASS = 0.0 V
VDD = 5.0 V, VSS = 0.0 V
VAREF = 5.000 V
VASS = 0.000 V
Unit
V
VSS
VASS
Analog Input Voltage
Nonlinearity Error
(VSS = 0 V, VDD = 4.5 to 5.5 V, Topr = −30 to 70°C)
⎯
0.5
1.0
⎯
⎯
±1
⎯
⎯
±1
⎯
⎯
±1
⎯
⎯
±2
mA
LSB
Total errors includes all errors, except quantization error.
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AC Characteristics
(VSS = 0 V, VDD = 4.5 to 5.5 V, Topr = −30 to 70°C)
Parameter
Symbol
Conditions
Min
In NORMAL1, 2 modes
Machine Cycle Time
tcy
0.32
In IDLE 1, 2 modes
tWCH
Low Level Clock Pulse Width
tWCL
High Level Clock Pulse Width
tWSH
Low Level Clock Pulse Width
tWSL
⎯
10
⎯
133.3
117.6
33.75
⎯
⎯
ns
For external clock operation
(XTIN input), fs = 32.768 kHz
14.7
⎯
⎯
μs
(VSS = 0 V, VDD = 4.5 to 5.5 V, Topr = −30 to 70°C)
Oscillation
Frequency
Oscillator
Recommended
Constant
Recommended Oscillator
C1
High-frequency
Oscillation
Low-frequency
Oscillation
Unit
For external clock operation
(XIN input), fc = 12.5 MHz
Recommended Oscillating Conditions
Parameter
Max
μs
In SLOW mode
In SLEEP mode
High Level Clock Pulse Width
Typ.
Ceramic Resonator
C2
12.5 MHz
Murata
CSA12.5MTZ
30 pF
30 pF
8 MHz
Murata
CSA8.00MTZ
30 pF
30 pF
Crystal Oscillator
12.5 MHz
NDK
AT-51
10 pF
10 pF
Crystal Oscillator
32.768 kHz
NDK
MX-38T
15 pF
15 pF
XIN
C1
XOUT
XTIN
C1
C2
(1) High-frequency Oscillation
XTOUT
C2
(2) Low-frequency Oscillation
Note 1: An electrical shield by metal shield plate on the surface of IC package should be recommendable in
order to prevent the device from the high electric fieldstress applied from CRT (Cathode Ray Tube)
for continuous reliable operation.
Note 2: The product numbers and specifications of the resonators
by Murata Manufacturing Co., Ltd. are subject to change.
For up-to-date information, please refer to the following URL;
http://www.murata.co.jp/search/index.html
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