SPRS292 − OCTOBER 2005

HOST-PORT INTERFACE TIMING (CONTINUED)

switching characteristics over recommended operating conditions during host-port interface cycles†‡ (see Figure 42, Figure 43, Figure 44, and Figure 45)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

GDPA−167

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

ZDPA−167

 

NO.

 

 

 

 

 

 

 

 

PARAMETER

−200

 

UNIT

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

−250

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

MIN

MAX

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

5

td(HCS-HRDY)

Delay time,

 

to

 

 

 

 

§

 

 

 

 

 

 

 

1

12

ns

HCS

HRDY

6

td(HSTBL-HRDYH)

Delay time,

 

 

 

 

low to

 

 

 

high

3

12

ns

HSTROBE

HRDY

7

td(HSTBL-HDLZ)

Delay time,

 

 

 

 

low to HD low impedance for an HPI read

2

 

ns

HSTROBE

 

8

td(HDV-HRDYL)

Delay time, HD valid to

 

 

low

2P − 4

 

ns

HRDY

 

9

toh(HSTBH-HDV)

Output hold time, HD valid after

 

 

 

high

3

12

ns

HSTROBE

15

td(HSTBH-HDHZ)

Delay time,

 

 

 

high to HD high impedance

3

12

ns

HSTROBE

16

td(HSTBL-HDV)

Delay time,

 

 

 

 

low to HD valid

3

12.5

ns

HSTROBE

17

td(HSTBH-HRDYH)

Delay time,

 

 

 

 

high to

 

 

 

high#

3

12

ns

HSTROBE

HRDY

HSTROBE refers to the following logical operation on HCS, HDS1, and HDS2: [NOT(HDS1 XOR HDS2)] OR HCS.

P = 1/CPU clock frequency in ns. For example, when running parts at 250 MHz, use P = 4 ns.

§HCS enables HRDY, and HRDY is always low when HCS is high. The case where HRDY goes high when HCS falls indicates that HPI is busy completing a previous HPID write or READ with autoincrement.

This parameter is used during an HPID read. At the beginning of the first half-word transfer on the falling edge of HSTROBE, the HPI sends the request to the EDMA internal address generation hardware, and HRDY remains high until the EDMA internal address generation hardware loads the requested data into HPID.

#This parameter is used after the second half-word of an HPID write or autoincrement read. HRDY remains low if the access is not an HPID write or autoincrement read. Reading or writing to HPIC or HPIA does not affect the HRDY signal.

88

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Motorola TMS320C6711D warranty Parameter, HCS Hrdy