Section 1
Introduction
This document describes the AT89EVK-01 evaluation kit dedicated to the AT83C24
Smart Card Reader Interface IC. This board is designed to allow an easy evaluation of
the AT83C24 on an application using the TDA8004.
This board can be connected on the TDA8004 footprint.
1.1
Features
The AT89EVK-01 provides the following features:
Possibility to replace the TDA8004 (or TDA8024) with the AT89EVK-01 board . The
AT89EVK-01 board is soldered on the TDA8004 footprint.
The AT83C24 registers are programmed with the TWI link (SDA,SCL). The
T89C5121 microcontroller sends the TWI commands to configure the AT83C24
registers.
The configuration software is stored in T89C5121 Flash memory. The program can be
reloaded by using FLIP / BatchISP (In-System Programming tool) and an RS-232
adaptor board (CEIBO for example).
Hardware configuration allowed with switches and solder pads.
The program can be modified and reloaded with Batchisp (see 2.2.2)
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Section 2
Hardware Description
2.1
2.1.1
TDA8004 Mode
Overview
The AT89EVK-01 board is soldered on the customer application by using the SO plug. If
there is a problem to connect the AT89EVK-01 board on the SO plug, connectors can
be added to lift the board.
Figure 2-1.
General Description
AT89EVK01board
AT83C24
extra connectors
SO plug
TDA8004 footprint
Customer board
Input signals of the TDA8004 footprint are connected to AT83C24.
Output signals of the TDA8004 footprint are provided by AT83C24.
The program stored in the Flash memory configures the AT83C24 registers once after
the reset. The functionalities of the TDA8004 are provided by the AT83C24.
Remarks:
The AT89EVK-01 board power supply comes from the TDA8004 footprint.
The program stored in the Flash memory configures the AT83C24 registers once after
the reset.
2.1.2
Clock signal (CLK)
The AT89EVK-01 board needs a clock signal. The AT89EVK-01 board needs a clock
signal for T89C5121 (XTAL1 pin) and for AT83C24 (CLK pin).
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Two solutions are proposed for the clock generation: waveform generator or crystal.
Figure 2-2.
External Waveform Generator for Clock
VSS
ATMEL
AT83C24 2.0.0
SO plug
AT89C5121
waveform
generator
XTAL1
VCC
RESET
Rx
Tx
SCL
SDA
AT83C24
Figure 2-3.
Crystal for Clock
AT83C24
VSS
ATMEL
AT83C24 2.0.0
SO plug
AT89C5121
14.74MHz
XTAL1
VCC
RESET
Rx
Tx
SCL
SDA
A solder pad (SW4) is used to configure the source: crystal or external waveform
generator.
Table 2-1.
Clock Solder Pads Configuration
SW4
without solder
with solder
Configuration
Waveform generator
crystal
2.1.3
Smart Card Clock
Signal (CCLK)
The AT83C24 outputs the smart card clock signal (CCLK). Two modes are available to
generate this signal:
1. The source is CLK. The CKS prescaler is used to divide CLK signal or DCCLK
signal.
2. The source is A2. The CKS prescaler is used to divide A2 signal.
2.1.4
Power Supply
The power supply comes from the TDA8004 footprint. The signal VDDP of the TDA8004
is used (5V).
The EVCC pin of the AT83C24 is connected to the VDD (3.3V). EVCC is used to supply
the AT83C24 pads connected to the customer application.
2.1.5
PRES, PRES\
The TWI_SEL switch is connected on an I/O of the T89C5121. The TDA8004
(TDA8024) PRES pin and PRES\ pin are connected on T89C5121 I/Os. The position of
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Hardware Description
the TWI_SEL switch selects the polarity of the smart card presence: information on
PRES or on PRES\ (see §2.1.8). See Figure 4-1 on page 16 for TWI_SEL selection.
Figure 2-4.
Power Supply Configuration
VDD TDA8004 (3.3V or 5V)
VDDP TDA8004 (5V)
L1
EVCC VCC
LI
AT83C24
Remark:
VCC and L1 must be connected to the same voltage.
2.1.6
TWI Link
The TWI link is managed by T89C5121. The program stored in the Flash memory con-
figures the AT83C24 registers once after the reset.
The T89C5121 sends TWI commands. The AT83C24 TWI address depends on level on
A2,A1,A0 pins at reset. The T89C5121 sends TWI commands at all addresses to avoid
any problem of level on A2, A1, A0 at reset.
2.1.7
External TWI Link
If the user wants to use an external TWI source to configure the AT83C24, the 2 test
points SCL and SDA are used.
To avoid any conflict with T89C5121 signals, the T89C5121 software must check the
SW2 signal before to send data on SCL and SDA.
2.1.8
Board configuration
The table below describes the switches and solder pads configurations.
Table 2-2.
Configuration Description
Solder pad
or Switch
SW1
SW2
Default
Configuration
no solder
TWI_SEL = 0
Description
RFU (TDA8004AT)
Smart card presence detection:
TWI_SEL = 0: PRES indicates the smart card presence.
TWI_SEL = 1: PRES\ indicates the smart card presence.
Reset button
with solder
solder
no solder
Used for clock configuration (see §2.1.2)
Used to connect TDA8004 clock on A2 (transparent
mode). Use firmware from version 3 (at89evk01_V3.zip)
Used to connect a pull up resistor on RESET pin
SW5
SW4
SW9
SW11
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