11. Signals and Pinout
195
PowerSpan II User Manual
80A1010_MA001_09
Integrated Device Technology
www.idt.com
PB_RST_
Bidirectional open
drain
(Schmitt trigger)
Low
(if PB_RST_DIR=1,
otherwise the signal
is an input)
Pull-up resistor
Reset:
Asynchronous active low
reset.
PB_RST_DIR
Input
-
Power-up option
Processor Bus Reset Direction
PB_TA_
Tristate bidirectional
Hi-Z
Pull-up resistor
Transfer Acknowledge:
Indicates that a data beat is valid
on the data bus. For single beat
transfers, it indicates the
termination of the transfer. For
burst transfers, it will be asserted
four times to indicate the transfer
of four data beats with the last
assertion indicating the
termination of the burst transfer.
PB_TBST_
Tristate bidirectional
Hi-Z
Pull-up resistor
Transfer Burst:
The bus master
asserts this pin to indicate that
the current transaction is a burst
transaction
PB_TEA_
Tristate bidirectional
Hi-Z
Pull-up resistor
Transfer Error Acknowledge:
Indicates a bus error.
PB_TSIZ[0:3]
Tristate bidirectional
Hi-Z
Pull-down resistor
on TSIZ[0]
b
Transfer Size:
Indicates the
number of bytes to be transferred
during a bus cycle.
PB_TS_
Tristate bidirectional
Hi-Z
Pull-up resistor
Transfer Start:
Indicates the
beginning of a new address bus
tenure.
PB_TT[0:4]
Tristate bidirectional
Hi-Z
No requirement
Transfer Type:
The bus master
drives these pins to specify the
type of the transaction.
PB_VDDA
Supply
-
-
PB Analog VDD:
Voltage supply
pin to the analog circuits in the PB
Phase Locked Loop (nominally
2.5V).
PB_DVDD
Supply
-
-
PB Digital VDD:
Voltage supply
pin to the digital circuits in the PB
Phase Locked Loop (nominally
2.5V).
Table 55: Processor Bus Signals
Pin Name
Pin Type
Reset State
Recommended
Termination
Description