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Zilog Z16C35 User Manual

Page 160

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Application Note

Interfacing Z80

®

CPUs to the Z8500 Peripheral Family

6-6

INPUT/OUTPUT CYCLES

(Continued)

.

Table 2. Z8500 Timing Parameters I/O Cycles

Worst Case

Min

Max

Units

6.

TsA(WR)

Address to /WR to Low Setup

80

ns

1.

TsA(RD)

Address to /RD Low Setup

80

ns

2.

TdA(DR)

Address to Read Data Valid

590

TsCEI(WR)

/CE Low to /WR Low Setup

ns

TsCEI(RD)

/CE Low to /RD Low Setup

ns

4.

TwRDI

/RD Low Width

390

ns

8.

TwWRI

/WR Low Width

390

ns

3.

TdRDf(DR)

/RD Low to Read Data Valid

255

ns

7.

TsDW(WR)

Write Data to /WR Low Setup

0

ns

Table 3. Z80A Timing Parameters I/O Cycles

Worst Case

Min

Max

Units

TcC

Clock Cycle Period

250

ns

TwCh

Clock Cycle High Width

110

ns

TfC

Clock Cycle Fall Time

30

ns

TdCr(A)

Clock High to Address Valid

110

ns

TdCr(RDf)

Clock High to /RD Low

85

ns

TdCr(IORQf)

Clock High to /IORQ Low

75

ns

TdCr(WRf)

Clock High to /WR Low

65

ns

5.

TsD(Cf)

Data to Clock Low Setup

50

ns

Table 4. Parameter Equations

Z8500
Parameter

Z80A
Equation

Value

Units

TsA(RD)

TcC-TdCr(A)

140 min

ns

TdA(DR)

3TcC+TwCh-TdCr(A)-TsD(Cf)

800 min

ns

TdRDf(DR)

2TcC+TwCh-TsD(Cf)

460 min

ns

TwRD1

2TcC+TwCh+TfC-TdCr(RDf)

525 min

ns

TsA(WR)

TcC-TdCr (A)

140 min

ns

TsDW(WR)

>0 min

ns

TwWR1

2TcC+TwCh+TfC-TdCr(WRf)

560 min

ns

Table 5. Parameter Equations

Z80A
Parameter

Z8500
Equation

Value

Units

TsD(Cf)

3TcC+TwCh-TdCr(A)-TdA(DR)

160 min

ns

/RD
2TcC+TwCh-TdCr(RDf)-TdRD(DR)

135 min

ns

Page 154 of 316

UM011002-0808