Zilog Z80230 Manual do Utilizador Página 128
- Página / 394
- Índice
- MARCADORES
Avaliado. / 5. Com base em avaliações de clientes
SCC/ESCC
User Manual
UM010903-0515 Data Communication Modes
121
The receiver automatically enters Hunt mode if an abort is received. Because the receiver always
searches the receive data stream for flags, and automatically enters Hunt Mode when an abort is
received, the receiver always handles frames correctly. The Enter Hunt Mode command should
never be needed. The SCC drives the /SYNC pin Low to signal that a flag has been recognized.
The timing for the /SYNC signal is displayed in Figure on page 121.
/SYNC as an Output
The SCC assumes the first byte in an SDLC frame is the address of the secondary station for which
the frame is intended. The SCC provides several options for handling this address.
If the Address Search Mode bit (D2) in WR3 is set to 0, the address recognition logic is disabled
and all received frames are transferred to the receive data FIFO. In this mode the software must
perform any address recognition.
If the Address Search Mode bit is set to 1, only those frames whose address matches the address
programmed in WR6 or the global address (all 1s) will be transferred to the receive data FIFO.
The address comparison is across all eight bits of WR6 if the Sync Character Load inhibit bit (D1)
in WR3 is set to 0. The comparison may be modified so that only the four most significant bits of
WR6 match the received address. This mode is selected by setting the Sync Character Load inhibit
bit to 1. In this mode, however, the address field is still eight bits wide. The address field is trans-
ferred to the receive data FIFO in the same manner as data. It is not treated differently than data.
The number of bits per character is controlled by bits D7 and D6 of WR3. Five, six, seven, or eight
bits per character may be selected via these two bits. The data is right-justified in the receive buf-
fer. The SCC merely takes a snapshot of the receive data stream at the appropriate times, so the
“unused” bits in the receive buffer are only the bits following the character.
State Changes in One
/RTxC Clock Cycle
/RTxC
PCLK
/SYNC
- SCC/ESCC 1
- UM010903-0515 2
- Revision History 3
- Table of Contents 4
- SCC’s Capabilities 9
- User Manual 13
- SCC Block Diagram 13
- Pin Descriptions 14
- Z85X30 DIP Pin Assignments 17
- Z85X30 PLCC Pin Assignments 18
- Z80X30 DIP Pin Assignments 19
- Interfacing the SCC/ESCC 24
- Z80X30 Write Cycle Timing 25
- Z80X30 Register Access 28
- Z80C30 Register Enhancement 31
- Z80230 Register Enhancements 32
- Z80X30 Reset 33
- Z85X30 Interface Timing 34
- Z85X30 Read Cycle Timing 35
- Z85X30 Write Cycle Timing 35
- D7-D0 Vector 36
- Z85X30 Register Access 37
- Z85C30 Register Enhancement 39
- Z85X30 Reset 41
- Interface Programming 42
- I/O Programming Introduction 43
- Interrupts 43
- External/Status Channel A 44
- Receive Channel B 44
- Transmit Channel B 44
- * Always 0 In B Channel 47
- Daisy-Chain Resolution 48
- Interrupt Acknowledge 51
- The Receiver Interrupt 52
- Receive Interrupts Disabled 53
- Conditio 56
- External/Status Interrupts 63
- Break/Abort 65
- Transmit Underrun/EOM 65
- CTS/DCD 66
- Zero Count 66
- Sync/Hunt 66
- Block/DMA Transfer 67
- SYNC Modes 68
- ASYNC Modes 68
- Wait On Receive 69
- DMA Requests 70
- DMA Request On Receive 74
- AD7-AD0 Receive DataWR8 75
- Test Functions 76
- Introduction 78
- Baud Rate Generator 78
- Data Encoding/Decoding 81
- Clock Selection 90
- Clock Multiplexer 92
- BRG Clock Source = /RTXC 93
- Crystal Oscillator 94
- Data Communication Modes 95
- Transmit Data Path 96
- Asynchronous Mode 99
- Asynchronous Transmit 100
- Asynchronous Receive 103
- Asynchronous Initialization 105
- Reg Bit No Description 107
- WR4 3 (=0) select sync mode 107
- State Changes in One 113
- /RTxC Clock Cycle 113
- SDLC Transmit 121
- SDLC Receive 127
- SDLC Frame Status FIFO 133
- Frame Status FIFO Circuitr 135
- Interface 135
- SDLC Loop Mode 137
- SDLC Loop Mode Receive 140
- SDLC Loop Mode Transmit 140
- Register Descriptions 143
- Write Registers 145
- Definition) 149
- Z85X30 Register Map 151
- Time Constant 175
- Clock Frequency 175
- Read Registers 181
- Read Register 1 185
- Read Register 2 187
- Read Register 3 188
- Read Register 8 191
- Read Register 10 192
- Read Register 12 193
- Read Register 13 194
- Read Register 15 194
- Application Notes 195
- Abstract 217
- Features 217
- Discussion 217
- Interfaces 218
- Z180 to Memory Interface 218
- EPROM Interface 220
- SRAM Interface 222
- SRAM Read Cycle 222
- SRAM Write Cycle 223
- Memory Interface Logic 223
- Physical Memory Address Map 225
- Z180 to I/O Interface 226
- Z180 I/O Write Cycle Timing 227
- Z180 to SCC Interface 230
- CPU Hardware Interfacing 230
- Data Bus Signals 230
- System Control Signals 230
- Interrupt Control 231
- SCC I/O Operation 231
- Read Cycle Timing 231
- Write Cycle Timing 232
- SCC Interrupt Operation 232
- Input/Output Cycles 234
- Z180 MPU to SCC Interface 234
- SCC I/O Read/Write Cycle 235
- I/O Read Cycle 235
- I/O Write Cycle 235
- Using EPLD 242
- System Checkout 243
- Software Considerations 244
- SCC Read Cycle Proof 244
- SCC Write Cycle Proof 244
- Interrupt Acknowledge Cycle 244
- (Continued) 246
- Summary 256
- General Description 257
- Processor 258
- Address Map 260
- (PBA)+511 269
- Serial Interfacing 270
- DMA channel 272
- Jumper Summary 276
- Control EPLD for 186 Board 278
- SCC EPLD for 186 Board 279
- DMA EPLD for 186 Board 280
- NMI Field for 186 Board 281
- Operation 295
- ESCC Controller 318
- Questions and Answers 382
- Customer Support 394
Manuais e produtos relacionados com Sensores Zilog Z80230
Sensores Zilog ZAURCT Manual do Utilizador
(59 páginas)
(59 páginas)
© 2020, manymanuals-pt.com. Todos os direitos reservados. | 0.058 s |
Manymanuals.com
Manymanuals.de
Manymanuals.fr
Manymanuals.it
Manymanuals.pl
Manymanuals.cz
Manymanuals.es
Manymanuals-pt.com
Comentários a estes Manuais