Parameters, Parameters –2 – Altera Avalon Verification IP Suite User Manual
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Chapter 2: Nios II Custom Instruction Slave BFM
Parameters
Avalon Verification IP Suite User Guide
May 2011
Altera Corporation
The Nios II Custom Instruction Slave BFM does not use queues to manage the
instructions or results. Without queues, the BFM uses events to retrieve the
instructions and to drive results. This method allows greater flexibility in controlling
the output result (for example, driving a result when the interface is unknown). If
there is an instruction and you do not provide the result, the BFM drives the old result
onto the interface. If there is no instruction at all, the BFM drives unknown (X) on the
interface.
Parameters
lists the parameter settings for the custom instruction master BFM interface.
Table 2–1. Custom Instruction Master BFM Parameter Settings
Option
Default
Value
Legal
Values
Description
General
Number of Operands to Use
2
0,1,2
Specifies the number of operands to use.
0: no operands are used.
1: use dataa port only.
2: use dataa and datab ports.
Fixed Length for Multi-cycle
Mode
2
—
Specifies the fixed length for multi-cycle mode.
Port Enables
Use Result Port
On
On/Off
When On, the interface includes a
result
pin.
Use Multi-cycle Mode
Off
On/Off
When On, the interface can include a
start
pin, a
done
pin,
both pins, or neither pins. The result returns in any of the
following conditions:
■
With a
start
signal—Result returns together with an
instruction.
■
Without a
start
signal—Result returns with instruction on
the bus at every clock cycle.
■
With a
done
signal—Result returns at any time.
■
Without a
done
signal—Result returns at a fixed cycle.
Using start port
On
On/Off
When On, the interface includes a
start
pin.
Using done port
On
On/Off
When On, the interface includes a
done
pin.
Use Extended Port
Off
On/Off
When On, the interface includes a
n
pin.
Extended Port Width
1
—
Specifies the width of the extended
n
port.
Use Internal Register a
Off
On/Off
When On, the interface includes the
readra
and
a
pins.
Use Internal Register b
Off
On/Off
When On, the interface includes the
readrb
and
b
pins.
Use Internal Register c
Off
On/Off
When On, the interface includes the
readrc
and
c
pins.