Datasheet

DS26514 4-Port T1/E1/J1 Transceiver
19-5856; Rev 4; 5/11 76 of 305
9.10.1.4 Receive HDLC-64 Example
The HDLC status registers in the DS26514 allow for flexible software interface to meet the user’s preferences.
When receiving HDLC messages, the host can choose to be interrupt driven, to poll to desired status registers, or a
combination of polling and interrupt processes can be used. An example routine for using the DS26514 HDLC
receiver is given in
Figure 9-17.
Figure 9-17. HDLC Message Receive Example
Reset Receive
HDLC Controller
(RHC.6)
Configure Receive
HDLC Controller
(RHC, RHBSE, RHFC)
Start New
Message Buffer
Enable Interrupts
RPE and RHWM
Start New
Message Buffer
Interrupt?
Read Register
RHPBA
Read N Bytes From
Rx HDLC FIFO (RHF)
N = RHPBA[5..0]
MS = 1?
(MS = RHPBA[7])
NO
YES
NO
YES
Read RRTS5 for
Packet Status (PS2..0)
Take appropriate action
No Action Required
Work Another Process.
Read N Bytes From
Rx HDLC FIFO (RHF)
N = RHPBA[5..0]
Start New
Message Buffer
Start New
Message Buffer