TSSIO16E ATMEL Corporation, TSSIO16E Datasheet - Page 10

• Manufacturer Part Number: TSSIO16E
• Description: Tssio16e Van Peripheral Circuit 16 Inputs-outputs
• Manufacturer: ATMEL Corporation

4.5
4.5.1
4.5.2
10
Example: Case of a LCD display with a TSSIO16E shared simul-
taneously by car radio and vehicle computer. In this case, the car
radio (B7 = 1) inhibits access to the display line until the full mes-
sage is displayed.
This access control strategy is only meaningful if the computer
(car radio or on-board computer) wants access to the peripheral
(display) and reads the control register to ensure that the periph-
eral is available. Writing to the port is never inhibited.
• After reset:
• During operation:
State on power on and safety mode
TSSIO16E
Condition for enter in safety mode (see Figure )
Condition for exit from safety mode
This table indicates the state of ports A and B and the INT pin on power on and changeover to
the safety mode. In power on mode the command register is initialized to 0.
Writing of port A is a way of exiting from the safety mode. Pin INT returns to 0.
• selection of RDX0 acces in automatic mode,
• line diagnosis activated,
• access free peripheral.
in the absence of writing or reading in the circuit for a SLTO
in the presence of coherent frames but the absence of reading or writing in the circuit for a LTO
INT pin
Port A
Port B
power-on
high Z
high Z
0
vehicle computer
car radio
VAN lines
VAN lines
LCD display with TSSIO16E
safety mode
unchanged
high Z
1
4421B–ASSP–10/05