beautypg.com

Spw-10x spacewire router – Atmel SpaceWire Router SpW-10X User Manual

Page 115

background image

Ref.: UoD_SpW-10X_

UserManual

Issue: 3.4

SpW-10X

SpaceWire Router

User Manual

Date: 11

th

July 2008

Preliminary

115

9.4.4 External port control/status register bits.

The port control/status fields specific to the External port are described in Table 9-7.

Table 9-7 External Port Control/Status Fields

Bits Name

Reset
Value

Description Read/Write

0

Error Active

‘0’

This bit is set to one when any of the error bits are set.

R

1 Packet

Address
Error

‘0’

The packet address error bit is set when a packet is
received with an incorrect address. A packet address
error is also generated when an empty packet is input
to the external port.

R

2 Output

port

timeout
error

‘0’

The output timeout error bit is set when the output port
has become blocked for a period of time.

R

3 Input

Buffer

Empty

‘0’

The external port input buffer is empty.

Note: The input buffer writes data to the SpaceWire
router.

R

4 Input

Buffer

Full

‘0’

The external port input buffer is full.

R

5 Output

Buffer
Empty

‘0’

The external output port buffer is empty.

Note: The output buffer writes data to the external
device connected to the external port.

R

6 Output

Buffer Full

‘0’

The external output port buffer is full.

R

23:5 Not

used

-

-

-

Note: The Error status bits are cleared by writing to the Error Active register, see section 9.5.4.

9.5 ROUTER CONTROL/STATUS REGISTERS

The router control/status registers are described below.

9.5.1 Network Discovery Register

The network discovery register address is 256 (0x0000 0100).

The network discovery register allows a network manager to determine the layout of the network by
reading the contents of the register. Its fields are shown in Figure 9-4 and described in Table 9-8.