Chapter 2 Hardware Essentials

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Status Port

Status Port

The Status Port is a read-only port. It contains information regarding the condition of the board during power-up/reset and during normal board operation. It is used to report:

A sequence of self-test codes while a reset is occurring.

An error code if self-test fails or a catastr ophic error occurs during normal operation.

Readiness of the board for commands (RDY bit).

Readiness for a new Single Command (ENT bit).

Status Port: Reset Format

The Status Port is 16 bits wide. The bit meanings of the port will be different depending on whether the status is General information or Reset information; each has separate formats. Both types of format are described in this section.

The RF3880 adapter performs a series of self-tests on reset or power-up. The Status Port is used by the RF3880 adapter to indicate the progress of the self- test as it is occurring. At power-up or reset, the Status Port will have this format:

BIT

15

14

13

12

 

11

10

9

8

7

6

5

4

3

2

1

0

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

0

 

 

 

 

Self-test Code (STC)

 

RDY

STC

Table 9: Status Port: Reset

Upon power-up or reset the following sequence will occur:

1.Soon after reset, the Status Port is written with a value of FDH.

2.Next, self-test begins and as it progresses, the Self-test Code fields are updated with the code of the test currently executing.

3.The RDY bit is zero during self-test to indicate the board cannot accept any command. All other fields of the Port (except Self-test Code (STC) fields) also remain zero as long as self-test continues.

4.The RDY bit will change to one if the self-tests complete successfully. The self-tests takes five seconds. If, after this time, the RDY bit is still zero, a self-test has failed.

If a self-test fails, the RDY bit will remain zero and the code of the test that failed will remain in the Self-test Code fields of the Status Port.

5.After the RF3880 self-tests complete successfully, and the RDY bit is set to one, the Status Port format will change to the General format.

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User’s Guide

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Ciprico Rimfire 3880 manual Status Port Reset Format, Hardware Essentials Status Port