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DS21Q55

Register Name:

 

 

INFO5, INFO6

 

 

 

 

 

 

Register Description:

 

HDLC #1 Information Register

 

 

 

 

 

 

 

 

HDLC #2 Information Register

 

 

 

 

Register Address:

 

2Eh, 2Fh

 

 

 

 

 

 

Bit #

7

6

5

4

3

2

1

0

 

Name

 

-

-

 

TEMPTY

TFULL

REMPTY

PS2

PS1

PS0

 

Default

 

0

0

 

0

0

0

0

0

0

 

Bits 0 to 2/Receive Packet Status (PS0 to PS2). These are real-time bits indicating the status as of the last read of the receive FIFO.

PS2

PS1

PS0

PACKET STATUS

0

0

0

In Progress: End of message has not yet been reached

0

0

1

Packet OK: Packet ended with correct CRC code word

0

1

0

CRC Error: A closing flag was detected, preceded by a corrupt CRC code word

0

1

1

Abort: Packet ended because an abort signal was detected (seven or more ones in

a row)

 

 

 

1

0

0

Overrun: HDLC controller terminated reception of packet because receive FIFO

is full

 

 

 

1

0

1

Message Too Short: Three or fewer bytes including CRC

Bit 3/Receive FIFO Empty (REMPTY). A real-time bit that is set high when the receive FIFO is empty.

Bit 4/Transmit FIFO Full (TFULL). A real-time bit that is set high when the FIFO is full.

Bit 5/Transmit FIFO Empty (TEMPTY). A real-time bit that is set high when the FIFO is empty.

Register Name:

INFO4

Register Description:

HDLC Event Information Register #4

Register Address:

2Dh

Bit #

Name

Default

7

6

5

4

3

2

1

0

 

 

 

 

H2UDR

H2OBT

H1UDR

H1OBT

0

0

0

0

0

0

0

0

Bit 0/HDLC #1 Opening Byte Event (H1OBT). Set when the next byte available in the receive FIFO is the first byte of a message.

Bit 1/HDLC #1 Transmit FIFO Underrun Event (H1UDR). Set when the transmit FIFO empties out without having seen the TMEND bit set. An abort is automatically sent. This bit is latched and will be cleared when read.

Bit 2/HDLC #2 Opening Byte Event (H2OBT). Set when the next byte available in the receive FIFO is the first byte of a message.

Bit 3/HDLC #2 Transmit FIFO Underrun Event (H2UDR). Set when the transmit FIFO empties out without having seen the TMEND bit set. An abort is automatically sent. This bit is latched and will be cleared when read.

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Please contact telecom.support@dalsemi.com or search http://www.maxim-ic.com for updated

information.

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Image 143
Maxim DS21Q55 specifications INFO5, INFO6, PS2 PS1 PS0 Packet Status, INFO4