TSC80C31/80C51
Rev. E (14 Jan.97)
1
MATRA MHS
Description
The TSC80C31/80C51 is high performance SCMOS
versions of the 8051 NMOS single chip 8 bit
C.
The fully static design of the TSC80C31/80C51 allows to
reduce system power consumption by bringing the clock
frequency down to any value, even DC, without loss of
data.
The TSC80C31/80C51 retains all the features of the 8051
: 4 K bytes of ROM ; 128 bytes of RAM ; 32 I/O lines ;
two 16 bit timers ; a 5-source, 2-level interrupt structure
; a full duplex serial port ; and on-chip oscillator and clock
circuits.
In addition, the TSC80C31/80C51 has two
software-selectable modes of reduced activity for further
reduction in power consumption. In the Idle Mode the
CPU is frozen while the RAM, the timers, the serial port,
and the interrupt system continue to function. In the
Power Down Mode the RAM is saved and all other
functions are inoperative.
The TSC80C31/80C51 is manufactured using SCMOS
process which allows them to run from 0 up to 44 MHz
with VCC = 5 V. The TSC80C31/80C51 is also available
at 20 MHz with 2.7 V < Vcc < 5.5 V.
D TSC80C31/80C51-L16 : Low power version
Vcc : 2.75.5 V
Freq : 016 MHz
D TSC80C31/80C51-L20 : Low power version
Vcc : 2.75.5 V
Freq : 020 MHz
D TSC80C31/80C51-12 : 0 to 12 MHz
D TSC80C31/80C51-20 : 0 to 20 MHz
D TSC80C31/80C51-25 : 0 to 25 MHz
D TSC80C31/80C51-30 : 0 to 30 MHz
D TSC80C31/80C51-36 : 0 to 36 MHz
D TSC80C31/80C51-40 : 0 to 40 MHz
D TSC80C31/80C51-44 : 0 to 44 MHz*
* Commercial and Industrial temperature range only. For other speed
and range please consult your sale office.
Features
D Power control modes
D 128 bytes of RAM
D 4 K bytes of ROM (TSC80C31/80C51)
D 32 programmable I/O lines
D Two 16 bit timer/counter
D 64 K program memory space
D 64 K data memory space
D Fully static design
D 0.8
m CMOS process
D Boolean processor
D 5 interrupt sources
D Programmable serial port
D Temperature range : commercial, industrial, automotive and
military
Optional
D Secret ROM : Encryption
D Secret TAG : Identification number
CMOS 0 to 44 MHz Single-Chip 8 Bit Microcontroller
TSC80C31/80C51
Rev. E (14 Jan.97)
2
MATRA MHS
Interface
Figure 1. Block Diagram
TSC80C31/80C51
Rev. E (14 Jan.97)
3
MATRA MHS
Figure 2. Pin Configuration
Diagrams are for reference only. Packages sizes are not to scale.
P1.4
P1.3
P1.2
P1.1
P1.0
NC
VCC
P0.0/A0
P0.1/A1
P0.2/A2
P0.3/A3
P0.4/A4
P1.5
P1.6
P1.7
RST
RxD/P3.0
NC
TxD/P3.1
INT0/P3.2
INT1/P3.3
T0/P3.4
T1/P3.5
P0.5/A5
P0.6/A6
P0.7/A7
EA
NC
ALE
PSEN
P2.7/A15
P2.6/A14
P2.5/A13
WR/P3.6
RD/P3.7
XT
AL2
XT
AL1
VSS
NC
P2.0/A8
P2.1/A9
P2.2/A10
P2.3/A1
1
P2.4/A12
15
P
16
P
17
P
30
RxD/P
31
TxD/P
32
INT0/P
33
INT1/P
34
T0/P
35
T1/P
36
WR/P
37
RD/P
XT
AL2
XT
AL1
SS
V
NC
20
P
21
P
22
P
23
P
24
P
RST
NC
14
P
13
P
12
P
11
P
10
P
NC
CC
V
00
P
/A8
/A9
/A10
/A1
1
/A12
04
P
/A4
05
P
/A5
06
P
/A6
07
P
/A7
EA
NC
ALE
PSEN
27
P /A15
26
P /A14
25
P /A13
/A0
01
P
/A1
02
P
/A2
03
P
/A3
DIL40
PLCC44
PQFP44
TSC80C31/80C51
Rev. E (14 Jan.97)
4
MATRA MHS
Pin Description
VSS
Circuit ground potential.
VCC
Supply voltage during normal, Idle, and Power Down
operation.
Port 0
Port 0 is an 8 bit open drain bi-directional I/O port. Port 0
pins that have 1's written to them float, and in that state
can be used as high-impedance inputs.
Port 0 is also the multiplexed low-order address and data
bus during accesses to external Program and Data
Memory. In this application it uses strong internal pullups
when emitting 1's. Port 0 also outputs the code bytes
during program verification in the TSC80C31/80C51.
External pullups are required during program
verification. Port 0 can sink eight LS TTL inputs.
Port 1
Port 1 is an 8 bit bi-directional I/O port with internal
pullups. Port 1 pins that have 1's written to them are
pulled high by the internal pullups, and in that state can
be used as inputs. As inputs, Port 1 pins that are externally
being pulled low will source current (IIL, on the data
sheet) because of the internal pullups.
Port 1 also receives the low-order address byte during
program verification. In the TSC80C31/80C51, Port 1
can sink or source three LS TTL inputs. It can drive
CMOS inputs without external pullups.
Port 2
Port 2 is an 8 bit bi-directional I/O port with internal
pullups. Port 2 pins that have 1's written to them are
pulled high by the internal pullups, and in that state can
be used as inputs. As inputs, Port 2 pins that are externally
being pulled low will source current (ILL, on the data
sheet) because of the internal pullups. Port 2 emits the
high-order address byte during fetches from external
Program Memory and during accesses to external Data
Memory that use 16 bit addresses (MOVX @DPTR). In
this application, it uses strong internal pullups when
emitting 1's. During accesses to external Data Memory
that use 8 bit addresses (MOVX @Ri), Port 2 emits the
contents of the P2 Special Function Register.
It also receives the high-order address bits and control
signals during program verification in the
TSC80C31/80C51. Port 2 can sink or source three LS
TTL inputs. It can drive CMOS inputs without external
pullups.
Port 3
Port 3 is an 8 bit bi-directional I/O port with internal
pullups. Port 3 pins that have 1's written to them are
pulled high by the internal pullups, and in that state can
be used as inputs. As inputs, Port 3 pins that are externally
being pulled low will source current (ILL, on the data
sheet) because of the pullups. It also serves the functions
of various special features of the TEMIC C51 Family, as
listed below.
Port Pin
Alternate Function
P3.0
P3.1
P3.2
P3.3
P3.4
P3.5
P3.6
P3.7
RXD (serial input port)
TXD (serial output port)
INT0 (external interrupt 0)
INT1 (external interrupt 1)
TD (Timer 0 external input)
T1 (Timer 1 external input)
WR (external Data Memory write strobe)
RD (external Data Memory read strobe)
Port 3 can sink or source three LS TTL inputs. It can drive
CMOS inputs without external pullups.
RST
A high level on this for two machine cycles while the
oscillator is running resets the device. An internal
pull-down resistor permits Power-On reset using only a
capacitor connected to V
CC
. As soon as the Reset is
applied (Vin), PORT 1, 2 and 3 are tied to one. This
operation is achieved asynchronously even if the
oscillator does not start-up.
ALE
Address Latch Enable output for latching the low byte of
the address during accesses to external memory. ALE is
activated as though for this purpose at a constant rate of
1/6 the oscillator frequency except during an external
data memory access at which time one ALE pulse is
skipped. ALE can sink/source 8 LS TTL inputs. It can
drive CMOS inputs without an external pullup.
If desired, ALE operation can be disabled by setting bit
0 of SFR location AFh (MSCON). With the bit set, ALE
is active only during MOVX instruction and external
fetches. Otherwise the pin is pulled low. MSCON SFR is
set to XXXXXXX0 by reset.
TSC80C31/80C51
Rev. E (14 Jan.97)
5
MATRA MHS
PSEN
Program Store Enable output is the read strobe to external
Program Memory. PSEN is activated twice each machine
cycle during fetches from external Program Memory.
(However, when executing out of external Program
Memory, two activations of PSEN are skipped during
each access to external Data Memory). PSEN is not
activated during fetches from internal Program Memory.
PSEN can sink or source 8 LS TTL inputs. It can drive
CMOS inputs without an external pullup.
EA
When EA is held high, the CPU executes out of internal
Program Memory (unless the Program Counter exceeds
3 FFFH). When EA is held low, the CPU executes only out
of external Program Memory. EA must not be floated.
XTAL1
Input to the inverting amplifier that forms the oscillator.
Receives the external oscillator signal when an external
oscillator is used.
XTAL2
Output of the inverting amplifier that forms the oscillator.
This pin should be floated when an external oscillator is
used.
Idle And Power Down Operation
Figure 3. shows the internal Idle and Power Down clock
configuration. As illustrated, Power Down operation
stops the oscillator. Idle mode operation allows the
interrupt, serial port, and timer blocks to continue to
function, while the clock to the CPU is gated off.
These special modes are activated by software via the
Special Function Register, PCON. Its hardware address is
87H. PCON is not bit addressable.
Figure 3. Idle and Power Down Hardware.
PCON : Power Control Register
(MSB)
(LSB)
SMOD
GF1
GF0
PD
IDL
Symbol
Position
Name and Function
SMOD
PCON.7
Double Baud rate bit. When set to
a 1, the baud rate is doubled when
the serial port is being used in
either modes 1, 2 or 3.
PCON.6
(Reserved)
PCON.5
(Reserved)
PCON.4
(Reserved)
GF1
PCON.3
General-purpose flag bit.
GF0
PCON.2
General-purpose flag bit.
PD
PCON.1
Power Down bit. Setting this bit
activates power down operation.
IDL
PCON.0
Idle mode bit. Setting this bit
activates idle mode operation.
If 1's are written to PD and IDL at the same time. PD
takes, precedence. The reset value of PCON is
(000X0000).
Idle Mode
The instruction that sets PCON.0 is the last instruction
executed before the Idle mode is activated. Once in the
Idle mode the CPU status is preserved in its entirety : the
Stack Pointer, Program Counter, Program Status Word,
Accumulator, RAM and all other registers maintain their
data during idle. Table 1 describes the status of the
external pins during Idle mode.
There are three ways to terminate the Idle mode.
Activation of any enabled interrupt will cause PCON.0 to
be cleared by hardware, terminating Idle mode. The
interrupt is serviced, and following RETI, the next
instruction to be executed will be the one following the
instruction that wrote 1 to PCON.0.
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