bt8375kpf Conexant Systems, Inc., bt8375kpf Datasheet - Page 86

• Manufacturer Part Number: bt8375kpf
• Description: Single Chip Transceivers For T1/e1 And Integrated Service Digital Network Isdn Primary Rate Interfaces Systems
• Manufacturer: Conexant Systems, Inc.

2.0 Circuit Description
2.8 Transmitter
Figure 2-31. Interrupt Driven Transmit Data Link Processing
2-58
0x00
0x20
0x40
0x60
Message
Block 1
Block 2
Block 3
Block 4
Interrupt Request register [IRR; addr 003] directing software to the lower levels.
Of all the interrupt sources, the 2 most significant bandwidth requirements are
signaling and data link interrupts. Each data link controller has a top-level
interrupt status register that reports data link operations (see Data Link 1 and 2
Interrupt Status registers [ISR2; addr 009, and ISR1; 00A]). The processor uses a
2-step interrupt scheme for the data link: it reads the Interrupt Request register,
then uses that register value to read the corresponding Data Link Interrupt Status
register.
Bt8370/8375/8376 uses a hierarchical interrupt structure, with 1 top-level
Write End of Message Register
Interrupt Service Routine
Write Block/Byte to FIFO
Write Block/Byte to FIFO
Read Interrupt Status
Transmit Message
Interrupt Occurred
Main Line Code
Link Near Empty
Transmit Data
Yes
Yes
Message
Interrupt
Return
Return
End of
Conexant
If
If
No
No
Fully Integrated T1/E1 Framer and Line Interface
Process Other Interrupt
Return
Return
Bt8370/8375/8376
N8370DSE