Rainbow Electronics AT88SA100S - Manual (Page 18)

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AT88SA100S [Preliminary]
8558A–SMEM–03/09
4.6. PauseLong
Forces the chip into a busy mode until the watchdog timer expires, after which it will automatically enter the sleep state.
During execution of this command the chip will ignore all activity on the IO signal. This command is used to prevent bus
conflicts in a system that also includes a CryptoAuthentication host chip sharing the same signal wire.
Table 19. Input Parameters
Name Size Notes
Opode PAUSELONG 1 0x01
Param1 Selector 1 Which chip to put into the pause state, 0x00 for all chips
Param2 Zero 2 Must be 0x00 00
Data Ignored 0
Table 20. Output Parameter
Name Size Notes
Success 1 If the command indicates that some other chip should go into the pause state, a
value of 0 will be returned by this AT88SA100S chip. If this chip goes into the
pause state no value will be returned.
The Selector parameter provides a mechanism to select which device will pause if there are multiple devices on the
bus:
• If the Selector parameter is 0x00, then every chip receiving this command will go into the pause state and no chip will
return a success code.
• If any of the bits of the Selector parameter are set, then the chip will read the values of Fuse[84-87] and go to sleep
only if those fuse values match the least significant 4 bits of the Selector parameter. If the chip does NOT go into the
pause state, it returns an error code of 0x0F. Otherwise it goes into the pause state and never returns any code.
5. Pinout
There are three pins on the chip.
Pin # Name Description
1 Signal IO channel to the system, open drain output. It is expected that an external pull-up resistor
will be provided to pull this signal up to V
CC
for proper communications. When the chip is not
in use this pin can be pulled to either V
CC
or V
SS
.
2 V
CC
Power supply, 2.5 – 5.5V. This pin should be bypassed with a high quality 0.1
μF capacitor
close to this pin with a short trace to V
SS
.
3 V
SS
Connect to system ground.