CN8478 Datasheet, PDF (92/221 Pages) Conexant Systems, Inc – Multichannel Synchronous Communications Controller (MUSYCC)

5.0 Memory Organization
5.1 Memory Architecture
CN8478/CN8474A/CN8472A/CN8471A
Multichannel Synchronous Communications Controller (MUSYCC™)
The first four sets of pointers for each channel group, listed in Table 5-2,
Group Structure Memory Map, are pointer locations exclusive to shared memory.
MUSYCC does not keep these values internally although they are accessed
regularly during channel processing. The remaining locations have a
corresponding register within MUSYCC.
Table 5-2. Group Structure Memory Map
Channel Group Memory Map
Transmit Head Pointers
Transmit Message Pointers
Receive Head Pointers
Receive Message Pointers
Transmit Time Slot Map
Transmit Sub Channel Map
Transmit Channel Configuration Table
Receive Time Slot Map
Receive Sub Channel Map
Receive Channel Configuration Table
Global Configuration Descriptor
Interrupt Queue Descriptor
Group Configuration Descriptor
Memory Protection Descriptor
Message Length Descriptor
Port Configuration Descriptor
Byte Offset from Respective
Group Base Pointer
00000h
00080h
00100h
00180h
00200h
00280h
00380h
00400h
00480h
00580h
00600h
00604h
0060Ch
00610h
00614h
00618h
Total Space Required
Length (Bytes)
128
128
128
128
128
256
128
128
256
128
4
8
4
4
4
4
1564
5.1.2 Memory Access Illustration
Assume the system memory controller (or the host) allocates addresses for
MUSYCC’s PCI functions as listed in Table 5-3.
Table 5-3. MUSYCC PCI Function Memory Allocation
System Allocated MUSYCC Memory Ranges
MUSYCC - Function 0- Base Address Register
EBUS - Function 1- Base Address Register
Start Address
0240 0000h
0340 0000h
End Address
024F FFFFh
034F FFFFh
Length
1 MB
1 MB
5-6
Conexant
100660E