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4.0 Electrical Specifications (Continued)
Fast Buffered Write of IMEM
Symbol 10# Parameter Formula Min Max Units
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ISU-RW-CO 1 RAE, REM-WR Falling before ClK-OUT Rising 14 ns
tH-RW-X 2 RAE, REM-WR Rising after XACK Rising 0 ns
tSU-CMD-CO 3 CMD Valid before ClK-OUT Falling 0 ns
tH-CMD-CO 4 CMD Invalid after ClK-OUT Falling 35 ns
tpD-RW-X 5 RAE, REM-WR Falling to XACK Falling 40 ns
tZA-LCL-AAD 6 A, AD Disabled before lCl Rising 2 ns
tAZ-LCL-AAD 7 A, AD Enabled before lCl Falling 17 ns
tPD-LCL-IA 8 lCl Falling to Next IA Valid T+ -30 0 ns
tPD-IWR-X 9 IWR Falling before XACK Rising (nIW+1)T+ -28 ns
tPD-X-IWR 10 XACK Rising to IWR Rising 0 ns
tZA-IWR-1 11 IWR Falling 10 I Enabled 0 ns
tAZ-IWR-1 12 IWR Rising to I Disabled 28 52 ns
tpD-I-IWR 13 I Valid before IWR Rising (nIW+1)T+ -26 ns
tW-IWR 14 IWRlowTime (nIW+1)T+ -12 ns
Note 1: All parameters are individually tested and guaranteed. Interpreting this data by numerically adding two or more parameters to create a new timing
specification may lead to invalid results.
Note 2: Two remote writes to instruction memory are necessary to store a 16~bit instruction word to IMEM-Iow byte followed by high byte. The timing of the 2nd
write is shown in this diagram. The timing of the first write is the same as a write of the PC or RIC.
Fast Buffered Write of IMEM
I~ ______________________________-JI
XACK ~
~ ------------------~
WRITE ------------------~--~--------------+_----------+_~~----
-I --CD - --0
AD,A :::::::::j--=-----~c::t:::::>----i:t::::=
~0-- --. CD.t.
~X
------------------------------------r----------r-----------------JII~--
@- --:;
I---------------------------~~~----------­
@_ ~@-o '~@
IWR -----------------------~~I
I,-~------------------
i+--@_
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