TDA8029 Philips Semiconductors, TDA8029 Datasheet - Page 11

• Manufacturer Part Number: TDA8029
• Description: Low power single card reader
• Manufacturer: Philips Semiconductors

Philips Semiconductors
8.1.1
Port 0 (P0.7 to P0.0): Port 0 is an open-drain,
bidirectional, I/O timer 2 generated commonly used baud
rates port. Port 0 pins that have logic 1s written to them
float and can be used as high-impedance inputs. Port 0 is
also the multiplexed low-order address and data bus
during access to external program and data memory.
In this application, it uses strong internal pull-ups when
emitting logic 1s. Port 0 also outputs the code bytes during
program verification and received code bytes during
EPROM programming. External pull-ups are required
during program verification.
Port 1 (P1.7 to P1.0): Port 1 is an 8-bit bidirectional
I/O-port with internal pull-ups. Port 1 pins that have
logic 1s written to them are pulled to HIGH level by the
internal pull-ups and can be used as inputs. As inputs,
port 1 pins that are externally pulled LOW will source
current because of the internal pull-ups. Port 1 also
receives the low-order address byte during program
memory verification. Alternate functions for port 1 include:
Port 2 (P2.7 to P2.0): Port 2 is an 8-bit bidirectional I/O
port with internal pull-ups. Port 2 pins that have logic 1s
written to them are pulled to HIGH level by the internal
pull-ups and can be used as inputs. As inputs, port 2 pins
that are externally being pulled to LOW will source current
because of the internal pull-ups. Port 2 emits the
high-order address byte during fetches from external
program memory and during access to external data
memory that use 16-bit addresses (MOVX @DPTR). In
this application, it uses strong internal pull-ups when
emitting logic 1s. During access to external data memory
that use 8-bit addresses (MOV @Ri), port 2 emits the
contents of the P2 special function register. Some port 2
pins receive the high order address bits during EPROM
programming and verification.
Port 3 (P3.7 to P3.3, P3.1 and P3.0): Port 3 is a 7-bit
bidirectional I/O port with internal pull-ups. Port 3 pins that
have logic 1s written to them are pulled to HIGH level by
the internal pull-ups and can be used as inputs. As inputs,
port 3 pins that are externally being pulled LOW will source
current because of the pull-ups.
2003 Oct 30
T2 (P1.0): Timer/counter 2 external count input / clock
out (see programmable clock out)
T2EX (P1.1): Timer/counter 2 reload/capture/direction
control.
Low power single card reader
P
ORT CHARACTERISTICS
11
Port 3 also serves the special features of the 80C51 family:
8.1.2
XTAL1 and XTAL2 are the input and output, respectively,
of an inverting amplifier. The pins can be configured for
use as an on-chip oscillator. To drive the device from an
external clock source, XTAL1 should be driven while
XTAL2 is left unconnected. There are no requirements on
the duty cycle of the external clock signal, because the
input to the internal clock circuitry is through a
divide-by-two flip-flop. However, minimum and maximum
HIGH and LOW times specified must be observed.
8.1.3
The microcontroller is reset when the TDA8029 is reset, as
described in Section 8.11.
8.1.4
This section describes the low power modes of the
microcontroller. Please refer to Section 8.15 for additional
information of the TDA8029 power reduction modes.
Stop clock mode: The static design enables the clock
speed to be reduced down to 0 MHz (stopped). When the
oscillator is stopped, the RAM and special function
registers retain their values. This mode allows
step-by-step utilization and permits reduced system power
consumption by lowering the clock frequency down to any
value. For lowest power consumption the Power-down
mode is suggested.
Idle mode: In the Idle mode, the CPU puts itself to sleep
while all of the on-chip peripherals stay active. The
instruction to invoke the Idle mode is the last instruction
executed in the normal operating mode before the Idle
mode is activated. The CPU contents, the on-chip RAM,
and all of the special function registers remain intact during
RxD (P3.0): Serial input port
TxD (P3.1): Serial output port
INT0 (P3.2): External interrupt 0 (pin INT0_N)
INT1 (P3.3): External interrupt 1 (pin INT1_N
T0 (P3.4): Timer 0 external input
T1 (P3.5): Timer 1 external input
WR (P3.6): External data memory write strobe
RD (P3.7): External data memory read strobe.
O
R
L
OW POWER MODES
ESET
SCILLATOR CHARACTERISTICS
Product specification
TDA8029