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SpaceWire Router |
| UserManual | |
Issue: | 3.4 | ||
User Manual | |||
Date: | 11th July 2008 | ||
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9.4.4 External port control/status register bits.
The port control/status fields specific to the External port are described in Table
Table
Bits | Name | Reset | Description | Read/Write |
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0 | Error Active | ‘0’ | This bit is set to one when any of the error bits are set. | R |
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1 | Packet | ‘0’ | The packet address error bit is set when a packet is | R |
| Address |
| received with an incorrect address. A packet address |
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| Error |
| error is also generated when an empty packet is input |
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| to the external port. |
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2 | Output port | ‘0’ | The output timeout error bit is set when the output port | R |
| timeout |
| has become blocked for a period of time. |
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| error |
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3 | Input Buffer | ‘0’ | The external port input buffer is empty. | R |
| Empty |
| Note: The input buffer writes data to the SpaceWire |
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| router. |
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4 | Input Buffer | ‘0’ | The external port input buffer is full. | R |
| Full |
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5 | Output | ‘0’ | The external output port buffer is empty. | R |
| Buffer |
| Note: The output buffer writes data to the external |
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| Empty |
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| device connected to the external port. |
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6 | Output | ‘0’ | The external output port buffer is full. | R |
| Buffer Full |
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23:5 | Not used | - | - | - |
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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
Preliminary | 115 |