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CY7C0430BV
CY7C0430CV
Document #: 38-06027 Rev. *B
Page 21 of 37
Counter Interrupt [37, 38, 39]
Mailbox Interrupt Timing[40, 41, 42, 43, 44]
Notes:
37. CE0 = OE = LB = UB = VIL; CE1 = R/W = CNTRST = MRST = CNTRD = MKRD = VIH.
38. CNTINT is always driven.
39. CNTINC goes LOW as the counter address masked portion is incremented from xx7Fh to xx00h. The “x” is “Don’t Care.”
40. CE0 = OE = LB = UB = CNTLD =VIL; CE1 = CNTRST = MRST = CNTRD = CNTINC = MKRD = MKLD =VIH.
41. Address “FFFE” is the mailbox location for Port 2.
42. Port 1 is configured for Write operation, and Port 2 is configured for Read operation.
43. Port 1 and Port 2 are used for simplicity. All four ports can write to or read from any mailbox.
44. Interrupt flag is set with respect to the rising edge of the write clock, and is reset with respect to the rising edge of the read clock.
Switching Waveforms (continued)
tSMLD
tHMLD
tSCLD
tHCLD
tCH2
tCL2
tCYC2
CLK
MKLD
CNTLD
An
xx7Eh
INTERNAL
ADDRESS
xx7Fh
xx00h
xx7Dh
EXTERNAL
ADDRESS
tSCINC
tHCINC
CNTINC
COUNTER
007Fh
xx7Dh
xx00h
CNTINT
tSCINT
tRCINT
tCH2
tCL2
tCYC2
CLKP1
tCH2
tCL2
tCYC2
CLKP2
FFFE
tSA
tHA
An+3
An
An+1
An+2
PORT-1
ADDRESS
Am
Am+4
Am+1
FFFE
Am+3
PORT-2
ADDRESS
INTP2
tSA
tHA
tSINT
tRINT