DRIVER SEND

 

ALLOCATE

 

 

 

 

Choose Bank Select

 

 

Register 2

Issue "Allocate Memory"

 

 

Command to MMU

 

 

 

 

Call ALLOCATE

Read Interrupt Status Register

 

Exit Driver Send

Yes

Allocation

No

 

 

Passed?

 

 

Read Allocation Result

 

 

 

Register

 

 

 

Write Allocated Packet into

 

Store Data Buffer Pointer

 

Packet # Register

 

 

 

 

 

Write Address Pointer Register

 

Clear "Ready for Packet" Flag

 

 

 

 

Copy Part of TX Data Packet

 

Enable Allocation Interrupt

 

into RAM

 

 

 

 

 

Write Source Address into

 

 

 

Proper Location

 

 

 

Copy Remaining TX Data

 

 

 

Packet into RAM

 

 

 

Enqueue Packet

 

 

 

Set "Ready for Packet" Flag

 

 

 

Return Buffers to Upper Layer

 

 

 

 

Return

 

FIGURE 15 - DRIVER SEND AND ALLOCATE ROUTINES

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SMC Networks SMC91C95 manual Driver Send and Allocate Routines