28478G-18 Mindspeed Technologies, 28478G-18 Datasheet - Page 130

• Manufacturer Part Number: 28478G-18
• Description: Multichannel Synchronous Communications Controller 208-Pin BGA
• Manufacturer: Mindspeed Technologies

Specifications of 28478G-18

• Package: 208BGA
• Maximum Data Rate: 32768 Kbps
• Transmission Media Type: Wire
• Power Supply Type: Analog
• Typical Supply Current: 250 mA
• Typical Operating Supply Voltage: 3.3 V
• Minimum Operating Supply Voltage: 3 V
• Maximum Operating Supply Voltage: 3.6 V

6.3.1
A group structure (one per supported group) must be allocated in shared memory. A data structure is instrumental
in keeping the memory spaces for the various descriptors required for a channel group configuration in a sequential
order and at exact offsets from the beginning of the group structure.
Once a group structure is allocated in shared memory, all descriptor spaces are allocated within the group
structure.
Service request handling within MUSYCC requires the group structure and descriptor contents be at an exact
offsets within the structure.
For this example, the following group structure declaration is used:
28478-DSH-002-E
/* Reference: Chapter “Memory Organization” */
#define SIZE_OF_GROUP_STRUCTURE 1564
#define NUM_GROUPS 1
#define BOUNDARY 2048
#define MUSYCC_FUNC_0_BAR 0x00900000 /* system usually assigns this */
/* declare variable */
typedef struct tGROUP_STRUCTURE
{
unsigned long *pGroupBase;
unsigned long *pDualAddressCycleBase;
unsigned long ServiceRequestDescr;
unsigned long InterruptStatusDescr;
unsigned char Txtime slotMap[128];
unsigned char TxSubchannelMap[256];
unsigned char TxChannelConfigDescr[128];
unsigned char Rxtime slotMap[128];
unsigned char RxSubchannelMap[256];
unsigned char RxChannelConfigDescr[128];
unsigned long GlobalConfigDescr;
unsigned long InterruptDescr[2];
unsigned long GroupConfigDescr;
unsigned long MemoryProtectDescr;
unsigned long MessageLengthDescr;
unsigned long PortConfigDescr;
} tGROUP_STRUCTURE;
/* IMPORTANT NOTE: Byte padding within the structure would cause descriptor */
/* offsets from the beginning of the structure to move. MUSYCC requires every */
/* offset to be fixed at all times. Byte padding is an automatic function of */
/* many compilers. */
/* allocate space */
tGROUP_STRUCTURE GroupStr0; /* one per supported group */
/* fixed descriptor offsets into the group structure */
#define GROUP_BASE_OFFSET...............0x00000000
#define DUAL_ADDRESS_CYCLE_BASE_OFFSET..0x00000004
#define SERVICE_REQUEST_OFFSET..........0x00000008
#define INTERRUPT_STATUS_OFFSET.........0x0000000C
#define TX_time slot_MAP_OFFSET..........0x00000200
#define TX_SUBCHANNEL_MAP_OFFSET........0x00000280
Group Structure
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