STC STC12C5A Series User manual

STC TECHNOLOGY Co.,Ltd.
STC12C5A08/16/32/60
8-bit micro-controller
This document contains information on a new product under development by STC.STC reserves the right to change or discontinue this
product without notice. 2007/12 version A1
Features.............................................................................................................................3
General Description..........................................................................................................4
Order Information:............................................................................................................4 
Pin Description..................................................................................................................5
Pin Definition............................................................................................................5
Pin Configuration......................................................................................................7
Block Diagram..................................................................................................................9
Address Map...........................................................................................................10
Bits Description ......................................................................................................11
Memory...........................................................................................................................13
Organization............................................................................................................13
RAM .......................................................................................................................13
Embedded Flash......................................................................................................14
ALE OUTPUT................................................................................................................15
Functional Description....................................................................................................17
I/O Port Configuration............................................................................................17
Timer/Counter.........................................................................................................21
BAUD-RATE GENERATOR(BRT).......................................................................25
Interrupt...................................................................................................................27
Watch Dog Timer....................................................................................................34
Universal Asynchronous Serial Port (UART).........................................................36
Secondary Universal Asynchronous Serial Port (S2) .............................................40
Programmable Counter Array (PCA)......................................................................45
Serial Peripheral Interface(SPI)..............................................................................55
Analog to Digital Converter....................................................................................63
Power Management ................................................................................................66
In System Programming and InApplication Programming....................................69
In System Programming (ISP)................................................................................69
In-Application Program (IAP)................................................................................72
Instructions Set................................................................................................................72
Absolute Maximum Rating (STC12C5Axx)..................................................................75
DC Characteristics (STC12C5Axx)................................................................................75
Absolute Maximum Rating (STC12LE5Axx)................................................................76
DC Characteristics (STC12LE5Axx) .............................................................................76
Package Dimension.........................................................................................................77
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2 STC12C5Axx Technical Summary
Version History ...............................................................................................................78
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STC12C5Axx Technical Summary 3
Features
zEnhanced 80C51 Central Processing Unit
z3.3V/5V operation voltage, built-in Low-Voltage Detector and Reset circuit
zOperation frequency range up to 25MHz
zMax 64K bytes on-chip flash memory with ISP/IAP capability
z256 byte scratch-pad RAM and 1024 bytes of auxiliary RAM
zTwo-level code protection for flash memory access
zTwo 16-bit timer/counter
z10 sources, 4-level-priority interrupt capability
zSecondary UART2 with self baud-rate generator
zOne enhanced UART with automatic address recognition and frame error detection
zSPI Master/Slave communication interface
z15 bits Watch-Dog-Timer with 8-bit pre-scalar, one-time enabled
zTwo Channel Programmable Counter Array (PCA)
z10-bit Analog-to-Digital Converter (ADC)
zPower control: idle mode and power-down mode, Power-down can be woken-up through
INT0 and INT1
z44(max) programmable I/O ports
zAlternative built-in 6MHz oscillator
zFully static operation
zExcellent noise immunity
zVery low power consumption
zPackage type:
-PDIP-40:
-LQFP-44
-PQFP-44
-PLCC-44
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4 STC12C5Axx Technical Summary
General Description
STC12C5Axx is a single-chip 8-bit micro-controller with instruction sets fully compatible with
industrial-standard 80C51 series micro controller.
There is very excellent MCU kernel built in this device compared to general 80C51 MCUs
those take twelve oscillating cycles to finish an instruction, the device could take only one
oscillating cycle to finish one instruction.
There is 8K(max) bytes flash memory embedded which could be used as program or data.
Also the In-System Programming and In-Application Programming mechanisms are
supported. The data endurance of the embedded flash gets over 20,000 times, and 21 years
data retention is guaranteed.
The operation frequency reaches at 25MHz. An user can apply a crystal oscillator for the
oscillating source, or alternatively uses the built in 6MHz RC oscillator to save system cost.
The built in 10Bits Analog-To-Digital Converter make it easy to sensing the environment or
implement a set of scan keys in low cost.
The UART interfaces make the device convenient to communicate with the peripheral
component, say talking to a personal computer via RS-232 port, or communicating with a
serial memory.
The Pulse-Width-Modulator (PWM) and Programmable Counter Array (PCA) make the device
to drive the peripheral step motor or LED in least cost.
The STC12xx is really the most efficient MCU adapted for simple control, say electronic
scales, remote controller, security encoder/decoder, and user interface controller.
Order Information:
Part Number Temperature
Range
Package Packing Operation
Voltage
12x5Aaa-bbb-cc-d-eee-ff -40℃~+85℃PDIP-40 Tray LE3.3V/ C:5V
12x5Aaa-bbb-cc-d-eee-ff -40℃~+85℃PLCC-44 Tray LE3.3V/ C:5V
12x5Aaa-bbb-cc-d-eee-ff -40℃~+85℃LQFP-48 Tray LE3.3V/ C:5V
12x5Aaa-bbb-cc-d-eee-ff -40℃~+85℃LQFP-44 Tray LE3.3V/ C:5V
.x: voltage aa: rom size bbb:ADC,PWM .or. none cc:active frequency
.d: temperature “I” for industrial eeee: package type ff: pin count
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STC12C5Axx Technical Summary 5
Pin Description
Pin Definition
MNEMONIC Package Type DESCRIPTION
PDIP40 PLCC44 PQFP44 LQFP48
P0.0 ~ P0.7 32-39 43-34 37-30 40-33 Port0: Port0 is an open-drain,
bi-directional IO port. When 1s are
written to Port0, they become
high-impedance inputs. Port0 is also
the multiplexed low-order address
and data bus during accesses to
external program and data memory.
P1.0 /ADC0/
CLKOUT2
P1.1/ADC1
P1.2/ADC2/ECI/
RXD2
P1.3/ADC3/CCPO/
TXD2
P1.4/ADC4/CCP1/SS
P1.5/ADC5/MOSI
P1.6/ADC6/MISO
P1.7/ADC7/SCLK
1
2
3
4
5
6
7
8
2
3
4
5
6
7
8
9
40
41
42
43
44
1
2
3
43
44
45
46
47
2
3
4
Port1: General-purposed I/O with
weak pull-up resistance inside. When
1s are written into Port1, the strong
output driving PMOS only turn-on two
period and then the weak pull-up
resistance keep the port high.
ADCn: Analog to Digital Converter
Input.
P2.0 ~ P2.7 21-28 24-31 18-25 19-23
26-28
Port2: Port2 is an 8-bit bi-directional
I/O port with pull-up resistance.
Except being as GPIO, Port2 emits
the high-order address byte during
accessing to external program and
data memory.
P3.0/RXD
P3.1/TXD
P3.2/INT0
P3.3/INT1
P3.4/T0/CLKOUT0
P3.5/T1/CLKOUT1
P3.6/WR
P3.7/RD
10-17 11
13
14
15
16
17
18
19
5
7
8
9
10
11
12
13
6
8
9
10
11
12
13
14
Port3: General-purposed I/O with
weak pull-up resistance inside. When
1s are written into Port1, the strong
output driving PMOS only turn-on two
period and then the weak pull-up
resistance keep the port high. Port3
also serves the special function of
STC12C5Axx.
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6 STC12C5Axx Technical Summary
P4.0/SS
P4.1/ECI/MOSI
P4.2/CCP0/MISO
P4.3/CCP1/SCLK
P4.4/NA
P4.5/ALE
P4.6/EX_LVD/RST2
P4.7/RST
29
30
31
9
23
34
1
12
32
33
35
10
17
28
39
6
26
27
29
4
18
31
42
7
29
30
32
5
Port4: Port4 are extended I/O ports
such like Port1. It can be available
only on 44L-PLCC, 44L-PQFP and
48L-LQFP.
ALE: Address Latch
EX_LVD: External Low Voltage Reset
Detector.
RESET 9 10 4 5
RESET: A high on this pin for at least
two machine cycles will reset the
device.
P5.0
P5.1
P5.2
P5.3
24
25
48
1
Port5: Port4 are extended I/O ports
such like Port1. It can be available
only on 48L-LQFP.
XTAL1 19 21 15 16
Crystal1: Input to the inverting
oscillator amplifier.
XTAL2 18 20 14 15
Crystal2: Output from the inverting
amplifier.
VDD 40 44 38 41
Power
VSS 20 22 16 17
Ground
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STC12C5Axx Technical Summary 7
Pin Configuration
CLKOUT2/P1.0
ECI/P1.2
CCP0/P1.3
SS/CCP1/P1.4
MOSI/P1.5
MISO/P1.6
SCLK/P1.7
RST/P4.7
RXD/P3.0
TXD/P3.1
INT0/P3.2
INT1/P3.3
CLKOUT0/T0/P3.4
CLKOUT1/T1/P3.5
WR/P3.6
RD/P3.7
P0.2/AD2
P0.3/AD3
P0.4/AD4
P0.5/AD5
P0.6/AD6
P0.7/AD7
EX_LVD/P4.6/RST2
ALE/P4.5
NA/P4.4
P2.7/A15
P2.6/A14
P2.5/A13
P2.4/A12
P2.3/A11
P2.2/A10
P2.1/A9
P2.0/A8
XTAL2
XTAL1
GND
P0.1/AD1
P0.0/AD0
VDD
1
20 21
40
PDIP-40
P1.1
STC12C5Axx
MOSI/P1.5
MISO/P1.6
SCLK/P1.7
RXD/P3.0
RST/P4.7
TXD/P3.1
INT0/P3.2
INT1/P3.3
CLKOUT0/T0/P3.4
CLKOUT1/T1/P3.5
P3.6/WR P3.7/RD XTAL2 XTAL1 GND P4.0/SS P2.0/A8 P2.1/A9 P2.2/A10 P2.3/A11 P2.4/A12
P0.4/AD4
P2.5/A13
SS/CCP1/P1.4
CCP0/P1.3
ECI/P1.2
CLKOUT2/P1.0
MISO/CCP0/P4.2
VDD
AD0/P0.0 AD1/P0.1 AD2/P0.2 AD3/P0.3
1
SCLK/CCP1/P4.3 STC12C5Axx
LQFP-48
P0.5/AD5
P0.6/AD6
P4.6/E_LVD/RST2
P0.7/AD7
P4.5/ALE
NA/P4.4
P2.7/A15
P2.6/A14
P4.1/ECI/MOSI
P5.0
P5.1
P5.3
P1.1 P5.2
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STC TECHNOLOGY Co.,Ltd.
STC12C5A08/16/32/60
8-bit micro-controller
This document contains information on a new product under development by STC.STC reserves the right to change or discontinue this
product without notice. 2007/12 version A1
MOSI.P1.5
MISO/P1.6
SCLK/P1.7
RXD/P3.0
RST/P4.7
TXD/P3.1
INT0/P3.2
INT1/P3.3
CLKOUT0/T0/P3.4
CLKOUT1/T1/P3.5
P3.6/WR P3.7/RD XTAL2 XTAL1 GND P4.0/SS P2.0/A8 P2.1/A9 P2.2/A10 P2.3/A11 P2.4/A12
P0.4/AD4
P0.5/AD5
P0.6/AD6
EX_LVD/P4.6/RST2
P0.7/AD7
P4.5/ALE
NA/P4.4
P2.7/A15
P2.6/A14
P2.5/A13
SS/CCP1/P1.4
CCP0/P1.3
ECI/P1.2
P1.1
CLKOUT2/P1.0
MISO/CCP0/P4.2
VDD
AD0/P0.0 AD1/P0.1 AD2/P0.2 AD3/P0.3
1
7
40
SCLK/CCP1/P4.3 P4.1/ECI/MOSI
18 29
STC12C5Axx
PLCC-44
MOSI/P1.5
MISO/P1.6
SCLK/P1.7
RXD/P3.0
RST/P4.7
TXD/P3.1
INT0/P3.2
INT1/P3.3
CLKOUT0/T0/P3.4
CLKOUT1/T1/P3.5
P3.6/WR P3.7/RD XTAL2 XTAL1 GND P4.0/SS P.0/A8 P2.1/A9 P2.2/A10 P2.3/A11 P2.4/A12
P0.4/AD4
P2.5/A13
SS/CCP1/P1.4
CCP0/P1.3
ECI/P1.2
CLKOUT2/P1.0
MISO/CCP0/P4.2
VDD
AD0/P0.0 AD1/P0.1 AD2/P0.2 AD3/P0.3
1
SCLK/CCP1/P4.3 STC12C5Axx
PQFP/LQFP-44
P0.5/AD5
P0.6/AD6
P4.6/EX_LVD/RST2
P0.7/AD7
P4.5/ALE
P4.4/NA
P2.7/A15
P2.6/A14
P4.1/ECI/MOSI
P1.1
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STC12C5Axx Technical Summary 9
Block Diagram
ALU
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10 STC12C5Axx Technical Summary
Special Function Register
Address Map
9 A B C D E F
F8 CH CCAP0H CCAP1H
F0 B PCAPWM0*PCAPWM1*
E8 CL CCAP0L CCAP1L
E0 ACC
D8 CCON CMOD CCAPM0 CCAPM1
D0 PSW
C8 P5 P5M1 P5M0 SPSTAT SPCTL SPDAT
C0 P4 WDT_CONTR IAP_DATA IAP_ADDRH IAP_ADDRL IAP_CMD IAP_TRIG IAP_CONTR
B8 IP SADEN P4SW ADC_CONTR ADC_RES ADC_RESL
B0 P3 P3M1 P3M0 P4M1 P4M0 IP2 IP2H IPHIPH
A8 IE SADDR
A0 P2 BUS_SPEED AUXR1 TEST_WDT
98 SCON SBUF S2CON S2SBUF BRT P1ASF
90 P1 P1M1 P1M0 P0M1 P0M0 P2M1 P2M0 CLK_DIV
88 TCON TMOD TL0 TL1 TH0 TH1 AUXR WAKE_CLK0
80 P0 SP DPL DPH PCON
* Write Only
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