notice. No liability is assumed as a result of the use of this procuts. No rights under any patent accompany the sales of th
TECHNOLOGY
GENERAL DESCRIPTION
MTU8B57E and 24 to 72 bytes of static RAM.
cycle instructions under 20MHz operating.
24 bytes for MTU8B55E,
PA3:PA0
512 X 14 TO
- XTAL : Standard crystal oscillator
EPROM-Based 8-Bit CMOS Microcontroller
FEATURES
• Total of 33 single word instructions .
• The fast execution time may be 200ns for all single
• Operating voltage range: 2.3V ~ 6.5V
• 8-bit data bus.
• 14-bit instruction word.
• Four-level stacks.
• On chip EPROM size : 512x14 bits for MTU8B54E/55E,
1Kx14 bits for MTU8B56E,
2Kx14 bits for MTU8B57E.
• Internal RAM size : 25 bytes for MTU8B54E/56E,
• 72 bytes for MTU8B57E.
• Direct and indirect addressing modes for data accessing
• 8-bit real time clock/counter with 8-bit programmable
prescaler.
• Internal power-on Reset.
• Device Reset Timer.
• Code protection.
• Sleep mode for power saving.
• On chip Watchdog Timer(WDT) based on internal RC
oscillator.
• Three I/O ports PA, PB nad PC with independent direc-
tion control.
MTU8B54E/55E/56E/57EMYSON
• 4 types of oscillator can be selected by code options:
- RC : Low-cost RC oscillator
- HFXTAL : High frequency crystal oscillator
- LFXTAL : Low frequency crystal oscillator
MTU8B5X series is an EPROM based 8-bit microcontroller which employs a full CMOS technology
enhanced with low-cost, high speed and high noise
immunity. W atchdog Timer, RAM, EPROM, tri-state
I/O port, power down mode, and real time programmable clock/counter are integrated into this chip.
MTU8B5X contains 33 instructions, all are single
cycle except for program branches which take two
cycles.
On chip memory is available with 512x14 bits of
EPROM for MTU8B54E/55E, 1Kx14 bits of EPROM
for MTU8B56E, 2Kx14 bits of EPROM for
BL OCK DIAGRAM
V
dd
V
ss
OSCI
OSCO
MCLR
T0CKI
Sleep
WDT/Timer0
Accumulator
Configuration
Word
Osc Mode
2
Select
Oscillator
Circuit
Prescaler
6
T0MODE
Register
6
Status
/Disable
Enable
WDT
Time Out
Four-level
Stack
WatchDog
Timer
Timer0
RAM
24, 25 or 27 Bytes
FSR
ALU
11
Data
8
8
Program
Counter
11
EPROM
2048 X 14
14
Instruction
Register
14
Instruction
Decoder
PortA
PortB
PortC
Only in MTU8B55E/57E
4
8
8
PB7:PB0
PC7:PC0
This datasheet contains new product information. Myson Technology reserves the rights to modify the product specification without
Revision 1.2 - 1 - 24 October 2000
e product.
Page 2
TECHNOLOGY
RC type: Input pin of RC oscillator
this pin is low, the device is reset.
In programmimg mode, this pin is connected to 12V. In normal operating
mode, this pin must not exceed Vdd to avoid entering unintended program-
PA0~PA3 as bi-directional I/O port
1.0 PIN CONNECTION
MTU8B54E/55E/56E/57EMYSON
PA2
PA3
T0CKI
MCLR/Vpp
Vss
PB0
PB1
PB2
PB3
1
2
3
4
MTU8B54E
5
MTU8B56E
6
7
8
9
2.0 PIN DESCRIPTIONS
NameI/ODescriptions
18
17
16
15
14
13
12
11
10
PA1
PA0
OSCI
OSCO
Vdd
PB7
PB6
PB5
PB4
T0CKI
Vdd
N/C
Vss
N/C
PA0
PA1
PA2
PA3
PB0
PB1
PB2
PB3
PB4
1
2
3
4
5
6
7
MTU8B55E
8
MTU8B57E
9
10
11
12
13
14
28
27
26
25
24
23
22
21
20
19
18
17
16
15
MCLR/Vpp
OSCI
OSCO
PC7
PC6
PC5
PC4
PC3
PC2
PC1
PC0
PB7
PB6
PB5
OSCII
OSCOO
T0CKI/SCLIInput pin of real time counter/clock. Must be tied to Vss or Vdd if not in use.
MCLR/VppI
PA0~PA3I/O
PB0~PB7I/OPB0~PB7 as bi-directional I/O port
PC0~PC7I/OPC0~PC7 as bi-directional I/O port
Vdd-Power supply
Vss-Ground
XTAL type: Input terminal of crystal oscillator
RC type: OSCO outputs with 1/4 frequency of OSCI to denotes the cycle
rate for instruction.
XTAL type: Output terminal of crystal oscillator
Input pin for device reset or high voltage programming input for EPROM. If
ming mode.
Revision 1.2 - 2 - 24 October 2000
Page 3
TECHNOLOGY
3.0 FUNCTIONAL DESCRIPTIONS
The Regis ter Map of MTU8B54E/56E
The Regist er Map of MTU8B55E
The Regi ster Map of MTU8B57E
Map back to address in Bank 0
3.1 REGISTER MAP
The register map of MTU8B5X is depicted as below:.
MTU8B54E/55E/56E/57EMYSON
AddressDescription
00hIndirect Addressing Register
01hTimer0
02hPC
03hSTA TUS
04hFSR
05hPORTA
06hPORTB
If d is “0”, the result is stored in the Acc register.
If d is “1”, the result is stored back in register R.
Affected
Decrement R, Skip if 0
Note : 1. The IOST registers are “write-only” and set upon RESET.
if the IOST latch is “1”, the corresponding I/O pin is in input mode.
MTU8B54E/55E/56E/57EMYSON
Mnem oni c
Descr ipti onCycl es
Operands
DECR R, dDecrement R101 0110 drrr rrrr Z
DECRSZ R, d
SUBAR R, dSubtract Acc from R101 1010 drrr rrrr C, DC, Z
XORAR R, dExclusive OR Acc with R101 1011 drrr rrrr Z
ANDAR R, dAND Acc with R101 0100 drrr rrrr Z
ADDAR R, dAdd Acc and R101 0101 drrr rrrr C, DC, Z
IORAR R, dInclusive OR Acc with R101 1111 drrr rrrr Z
Note:b : Bit position
Acc : Accumulator
PD : Power down flagTO
Z : Zero flagC : Carry flag
I : (i7i6i5i4i3i2i1i0)R : (r6r5r4r3r2r1r0)
d 01,[ ]∈
:Destination
1 or
2(skip)
Instruction
Status
Code
01 0111 drrr rrrr None
R : Register address
Acc Data
IOST R
Data Bus
WR Port
2. If the IOST latch is “0”, the corresponding I/O pin is in output mode;
D
IOST
Latch
CK
D
Data
Latch
CK
QB
QB
Q
Q
RD Port
VDD
VSS
I/O Pin
Revision 1.2 - 8 - 24 October 2000
Page 9
MTU8B54E/55E/56E/57EMYSON
reset (normal operation).
(3) WDT reset (normal operation).
wake-up (from sleep mode).
(5) WDT wake-up (from sleep mode) : Executing the SLEEP instruction can force this device entering into
sleep mode (power saving mode). While in sleep mode, the WDT is cleared but keeps running. This
Note: x = unknown, u = unchanged, - = unimplemented, read as “0”,
Power-On Reset
/MCLR or WDT Reset
111 1 1111
111 1 11 11
111 1 1111
111 1 11 11
--1 1 11 1 1
WDT Reset (not during SLEEP)
WDT Reset during SLEEP
TECHNOLOGY
3.4 RESET
This device may be reset by one of the following ways:
(1) Power-on Reset : At power-up, this device will be kept in a RESET condition for a period of 18ms after
the voltage on MCLR/Vpp pin has reached a logic high level.
(2) MCLR
(4) MCLR
device can be awakened by WDT time-out or reset input on MCLR pin.
The contents of registers after reset are listed below:
ConditionStatus:bit 4Status:bit 3
/MCLR Reset (not during SLEEP)uu
/MCLR Reset during SLEEP10
01
00
Revision 1.2 - 9 - 24 October 2000
Page 10
MTU8B54E/55E/56E/57EMYSON
Timer0 is an 8-bit timer/counter. The clock source of T imer0 can come from the internal clock or by an external
To select the internal clock source, bit 5 of the T0MODE register should be reset. In this mode, Timer0 will
To select the external clock source, bit 5 of the T0MODE register should be set. In this mode, Timer0 will
Wat c h dog Timer (WDT)
The Watchdog Timer is a free running on-chip RC oscillator. This RC oscillator is separated from the RC oscil-
as in sleep mode. During normal operation or in sleep mode, a WDT time-out will cause the device reset and
Without prescaler, the WDT time-out period is 18ms. This period can be increased by using the prescaler . The
the Timer0. The PS2:PS0 bits determine the prescale ratio. When assigned to Timer0, the prescaler will be
cleared by instructions which write to Timer0 Register. A CLRWDT instruction will clear the WDT and pres-
caler when assigned to WDT. The prescaler can not be assigned to both the Timer0 and WDT simultaneously.
WDT enable
WDT Time-Out
TECHNOLOGY
3.5 REAL TIME CLOCK (TIMER0) AND WATCHDOG TIMER
T0CKI
F
TE
OSC
/4
1
M
U
0
X
TS
PSC
1
MUX
0
PSC
0
WDT
1
MUX
Sync
2 cycles
Timer0
8 bits
Data Bus
3.5.1 Timer0
clock source presented at the T0CKI pin.
increase by 1 in every instruction cycle (without prescaler).
increase by 1 on every falling or rising edge of T0CKI pin is controlled by bit 4 of T0MODE register.
PS2:PS0
8-bit prescaler
PSC
8 bits
8-to-1 MUX
1
0
MUX
3.5.2
lator of the OSCI pin. That means the WDT will keep running even when the oscillator driver is turned off, such
the TO bit (bit 4 of STATUS register) will be cleared.
division ratio of prescaler is up to 1:128. Thus, the longest time-out period is approximately 2.3s.
3.5.3 Pr esc aler
The 8-bit prescaler may be assigned to either the Timer0 or the WDT through the PSC bit (bit 3 of the
T0MODE register). Setting this bit assigns the prescaler to the WDT. Resetting this bit assigns the prescaler to
Revision 1.2 - 10 - 24 October 2000
Page 11
MTU8B54E/55E/56E/57EMYSON
3.6 OSCILLATOR CONFIGURATION
mode. These oscillator modes offered as:
• RC: Low-cost crystal
• XTAL: Standard crystal oscillator
XTAL, HFXTA L or LFXTAL m odes
3.7 CONFIGURATION WORD
external system
Watchdog Timer enable
Watchdog Timer disable
TECHNOLOGY
This device supports four oscillator modes. Users can program two configuration bits to select the appropriate
• HFXTAL: High frequency crystal oscillator
• LFXTAL: Low frequency crystal oscillator
3.6.1
MTU8B54E/55E/56E/57E
Internal
Circuit
SLEEP
MTU8B54E/55E/56E/57E
OSCI
C
1
(a) Crys t al Operatio n (or Ceramic Resonato r )
3.6.2 RC Osc il l ator Mode
R
C
Bit 3
Code Protect
1
0
x
x
x
x
x
x
Bit2
WDT Enable
x
x
1
0
x
x
x
x
OSCO
RF
XTAL
OSCO
Oscillator Type
OSCI
RS
C
Bit1
x
x
x
x
1
1
0
0
2
(b) Ext ernal Clock Input Operation
MTU8B54E/55E/56E/57E
internal
clock
0 4÷
Bit0
Oscillator Type
x
x
x
x
1
0
1
0
EPROM unprotected
EPROM protected
RC
HFXTAL
XTAL
LFXTAL
OSCI
Clock from
FunctionRemark
OSCO
Open
Default
Default
Default
Revision 1.2 - 11 - 24 October 2000
Page 12
MTU8B54E/55E/56E/57EMYSON
4.0 ABSOLUTE MAXIMUM RATINGS
Ambient Operating Temperature
Store T emperature
DC Supply Voltage(V
Voltage with respect to Ground(V
5.0 OPERATING CONDITIONS
DC Supply Voltage
Operaing Temprature
6.0 ELECTRICAL CHA RACTERISTICS
=-5.4mA,
=8.7mA in RC mode
WDT Enable, V
WDT Disable, V
HFXTAL: 24MHz, WDT Disable
LFXTAL: 32kHz, WDT Disable
XTAL: 12MHz, WDT Disable
TECHNOLOGY
-55oC to +125oC
-65oC to +150oC
)0V to +7.5V
dd
)0.6V to (Vdd + 0.6)V
ss
Voltage on MCLR(Vpp) with respect to Ground(Vss)0V to +12V