Cpu runs other application code – Maxim Integrated High-Speed Microcontroller Users Guide: Network Microcontroller Supplement User Manual
Page 185
High-Speed Microcontroller User’s
Guide: Network Microcontroller
Supplement
185
Figure 22-12. Transmit Flow Diagram
CPU
Load transmit data buffer memory (MOVXs)
Write BCUD SFR
(Data buffer size/location)
1) msbyte of 11-bit transmit buffer byte count [00–06h]
2) lsbyte of 11-bit transmit buffer byte count [00–FFh]
3) Starting page of transmit buffer [00–1Fh]
Write BCUC SFR
With transmit request command:
BCUC.3-0
Command
0100
Transmit — Normal
0101
Transmit—No zero-padding of data
0110
Transmit—No FCS appended
ETHERNET CONTROLLER
BCU
CPU RUNS OTHER
APPLICATION CODE
BCU services transmit request
1) Transmit attempt by MAC completes or aborts
2) Transmit status word written to the data buffer
3) Transmit interrupt flag (TIF) set to 1
Ethernet activity interrupt request (if enabled)
1) Read BCUC to find TIF = 1
2) Read transmit status word for packet handling
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