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Scsi timer zero (stime0), Register: 0x48 – Avago Technologies LSI53C1010R User Manual

Page 198

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4-80

Registers

Version 2.2

Copyright © 2000–2003 by LSI Logic Corporation. All rights reserved.

GPIO[4:2]

GPIO Enable

[4:2]

The general purpose control corresponds to bits [4:2] in
the

General Purpose (GPREG)

register and to the

GPIO4–GPIO2 pins. GPIO4 powers-up as a
general purpose output. GPIO[3:2] power-up as
general purpose inputs.

GPIO[1:0]

GPIO Enable

[1:0]

These bits are set at power-up causing the GPIO1 and
GPIO0 pins to become inputs. Clearing these bits cause
GPIO[1:0] to become outputs.

Register: 0x48

SCSI Timer Zero (STIME0)
Read/Write

HTH[3:0]

Handshake-to-Handshake Timer Period

[7:4]

These bits select the handshake-to-handshake time-out
period, which is the maximum time between SCSI
handshakes (SREQ/ to SREQ/ in target mode; or,
SACK/ to SACK/ in the initiator mode). When this timing
is exceeded, an interrupt is generated and the HTH bit in
the

SCSI Interrupt Status One (SIST1)

register is set.

The following table contains time-out periods for the
Handshake-to-Handshake Timer, the
Selection/Reselection Timer (bits [3:0]), and the
General Purpose Timer (

SCSI Timer One (STIME1)

bits

[3:0]). For a more detailed explanation of interrupts, refer
to

Chapter 2, “Functional Description.”

7

4

3

0

HTH[3:0]

SEL[3:0]

0

0

0

0

0

0

0

0