Cypress CYDC064B16, CYDC064B08, CYDC256B16 manual Semaphore Read After Write Timing, Either Side49

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CYDC256B16, CYDC128B16,

CYDC064B16, CYDC128B08,

CYDC064B08

Switching Waveforms (continued)

Semaphore Read After Write Timing, Either Side[49, 50]

		tSAA	tOHA
A0–A2	VALID ADRESS	VALID ADRESS
	tAW	tACE
	tHA	tACE
SEM	tHA
SEM	tSCE	tSOP
	tSCE	tSOP
	tSD
I/O0	DATAIN VALID		DATAOUT VALID
	DATAIN VALID		DATAOUT VALID
tSA	tHD
tSA	tPWE
R/W
	tSWRD	tDOE
OE		tSOP
	WRITE CYCLE	READ CYCLE

Timing Diagram of Semaphore Contention[51, 52]

A0L–A2L

R/WL

SEML

A0R–A2R

R/WR

SEMR

MATCH

tSPS

MATCH

Notes:

49.If the CE or SEM LOW transition occurs simultaneously with or after the R/W LOW transition, the outputs remain in the high-impedance state.

50.CE = HIGH for the duration of the above timing (both write and read cycle).

51.I/O0R = I/O0L = LOW (request semaphore); CER = CEL = HIGH.

52.If tSPS is violated, the semaphore will definitely be obtained by one side or the other, but which side will get the semaphore is unpredictable.

Document #: 001-01638 Rev. *E

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Contents Features Selection Guide for VCC =CYDC256B16, CYDC128B16 CYDC064B16, CYDC128B08 CYDC064B08 UnitCYDC256B16, CYDC128B16 Pin Configurations 3, 4, 5, 6 Pin Tqfp Top ViewPin Configurations 7, 8, 9 CYDC064B08Pin Definitions Functional DescriptionInterrupts BusyMaster/Slave Input Read RegisterArchitecture 0 -I/O 2 -I/O Mode 0 -I/O 5 -I/O ModeInput Read Register Operation16 Semaphore Operation Example FunctionElectrical Characteristics for V CC = Range Ambient TemperatureMaximum Ratings23 Operating RangeInput Leakage Current Standb y Cur rent One Port Cmos IndOutput LOW Voltage I OL = 2 mA 5V any port 0V any port ODR Output LOW Voltage I OL = 8 mA 5V any port 0V any portInput High Voltage 5V any port Input LOW Voltage 5V any port 0V any portCapacitance Parameter Description Test Conditions Max UnitAC7Test Loads and Waveforms Write CycleSemaphore Timing Busy TimingInterrupt Timing High after Slave Data Hold From Write End Document # 001-01638 Rev. *E SEM Address Access Time Document # 001-01638 Rev. *E Switching Waveforms Read Cycle No.1 Either Port Address Access36, 37Read Cycle No.2 Either Port CE/OE Access36, 39 Read Cycle No Either Port36, 38, 41Write Cycle No CE Controlled Timing 41, 42, 43 Timing Diagram of Semaphore Contention51 Semaphore Read After Write Timing, Either Side49Timing Diagram of Read with Busy M/S=HIGH53 Write Timing with Busy Input M/S = LOWRight Address Valid First Busy Timing Diagram No.1 CE Arbitration CEL Valid First54CER Valid First Interrupt Timing Diagrams Left Side Sets INT R Right Side Clears INT RRight Side Sets Intl Left Side Clears INT LOrdering Information Package Diagram Pin Thin Plastic Quad Flat Pack Tqfp A100Issue Date Orig. Description of Change Document History