Motorola MC68824 User Manual page 7

Paragraph
Number
4.1.1.2
4.1.1.3
4.1.1.4
4.1.1.5
4.1.1.6
4.1.1.7
4.1.1.8
4.1.1.9
4.1.1.10
4.1.2
4.1.2.1
4.1.2.2
4.1.2.3
4.1.2.4
4.1.2.5
4.1.3
4.2
4.2.1
4.2.2
4.2.3
4.2.4
4.2.5
4.3
4.3.1
4.3.2
4.3.3
4.4
4.5
TABLE OF CONTENTS (Continued)
Page
Title Number
Receive Status Word ..... ................................. ...................... 4-5
Control for Next Frame Descriptor Pointer............. .................... 4-5
Next Frame Descriptor Pointer ..... ............ ..... ........... ............... 4-6
First Buffer Descriptor Pointer.............. ........ ................. ....... ... 4-6
Frame Data Length............................................................... 4-6
Immediate Response Frame Descriptor Pointer.......................... 4-6
Frame Control..................................................................... 4-6
MAC Destination Address...................................................... 4-6
MAC Source Address............................................................ 4-6
Buffer Descriptors....... ..... .... ....................................... ............... 4-6
Data Buffer Pointer............................................................... 4-7
Buffer Descriptor Control and Offset ......................... ............... 4-7
Buffer Length...................................................................... 4-8
Receive Indication Word........................................................ 4-8
Next Buffer Descriptor Pointer....... ..... .... ........... ..................... 4-8
Data Buffers.. .......... ............. .................... ................................ 4-8
Transmission of a Frame.... ......... .... ................... .................... .......... 4-8
Initialization Performed by Host.................................................... 4-9
Management of Transmission Queues........................................... 4-9
Examples of TBC Transmission Queues......................................... 4-10
Adding a Frame to a Transmission Queue...................................... 4-11
TBC's Actions Upon Transmission ................................. ............... 4-11
Reception of Frames............................................. ..................... ...... 4-12
Initialization Performed by Host............................... .... ................. 4-12
Reception Queues and Free Pools ............................ ... ............ ...... 4-13
TBC's Action Upon Reception ...................................................... 4-14
Request with Response (RWR) Transmission ........................................ 4-15
Reception of RWR Frames and Transmission of Response ...... ............ ..... 4-16
Section 5
Signals
5.1 Address Bus (A1-A31) ...................................................................... 5-1
5.2 Data Bus (00-015)........................................................................... 5-1
5.3 Bus Control ................................................................................... 5-1
5.3.1 Function Codes (FCO-FC3) ........................................................... 5-1
5.3.2 Bus Exception Conditions (BECO-BEC2) ............................... ..... ...... 5-2
5.3.3 Data Transfer Acknowledge (DTACK) ............................................. 5-3
5.3.4 ReadIWrite (RIW)....................................................................... 5-3
5.3.5 Upper Data Strobe (UDS/AO), Lower Data Strobe (LOS/OS).... ....... ...... 5-3
5.3.6 Address Strobe (AS) .................................................................. 5-3
5.3.7 Chip Select (CS) ....... ........................... ................................ ...... 5-4
5.4 Bus Arbitration............................................................................... 5-4
5.4.1 Bus Request (BR) ...................................................................... 5-4
5.4.2 Bus Grant (BG) ... ..... ............. .......... ..... ............. ... ........... .......... 5-4
5.4.3 Bus Grant Acknowledge (BGACK) ................................................. 5-4
MOTOROLA
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MC68824 USER'S MANUAL