Rainbow Electronics DS26519 - Manual (Page 88)

DS26519 16-Port T1/E1/J1 Transceiver
88 of 310
Figure 9-19. HDLC Message Transmit Example
Reset Transmit
HDLC Controller
(THC.5)
Configure Transmit
HDLC Controller
(THC1,THC2,THBSE,THFC)
TLWM
Interrupt?
Enable TMEND
Interrupt
No Action Required
Work Another Process
Enable TLWM
Interrupt and
Verify TLWM Clear
Read TFBA
N = TFBA[6..0]
Push Message Byte
into Tx HDLC FIFO
(THF)
Last Byte of
Message?
YES
NO
Set TEOM
(THC1.2)
Push Last Byte
into Tx FIFO
Loop N
TMEND
Interrupt?
YES
Read TUDR
Status Bit
TUDR = 1
YES
Disable TMEND Interrupt
Resend Message
Disable TMEND Interrupt
Prepare New
Message
YES
NO
NO
NO
A
A
A