Rainbow Electronics AT88SA100S - Manual (Page 8)

8
AT88SA100S [Preliminary]
8558A–SMEM–03/09
3.1. IO Flags
The host system is always the bus master, so before any IO transaction, the system must first send an 8 bit flag to the
chip to indicate the IO operation that is to be performed, as follows:
Value Name Meaning
0x77 Command
After this flag, the system starts sending a command block to the chip. The first bit of the
block can follow immediately after the last bit of the flag.
0x88 Transmit
After a turn-around delay, the chip will start transmitting the response for a previously
transmitted command block.
0xCC Sleep
Upon receipt of a sleep flag, the chip will enter a low power mode until the next wake token
is received.
All other values are reserved and will be ignored.
3.1.1. Command Timing
After a command flag is transmitted, a command block should be sent to the chip. During parsing of the parameters
and subsequent execution of a properly received command, the chip will be busy and not respond to transitions on the
signal pin. The delays for these operations are listed in the table below:
Table 5. Command Timing
Parameter Symbol
Mi
n
Max Unit Notes
ParsingDelay t
PARSE
0 50 μs
Delay to check CRC and parse opcode and parameters
before an error indication will be available
MemoryDelay t
EXEC_MEM
50 100
μs Delay to execute Read, Write and/or SramLock commands
FuseDelay t
EXEC_FUSE
150 300
μs Delay to execute BurnFuse commands
MacDelay t
EXEC_MAC
15 30 ms Delay to execute MAC command
PersonalizeDelay t
PERSON
7 15 ms Delay to execute GenPersonalizationKey or LoadSram
In this document, t
EXEC
is used as shorthand for the delay corresponding to whatever command has been sent to the
chip.