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547 lines
19 KiB
C
547 lines
19 KiB
C
// cs8900a.c: device driver for the CS8900a chip in 8-bit mode.
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#include <LPC210x.h>
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#include "cs8900a.h"
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#include "uip.h"
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#include "uip_arp.h"
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#define IOR (1<<12) // CS8900's ISA-bus interface pins
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#define IOW (1<<13)
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// definitions for Crystal CS8900 ethernet-controller
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// based on linux-header by Russel Nelson
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#define PP_ChipID 0x0000 // offset 0h -> Corp-ID
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// offset 2h -> Model/Product Number
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#define LED_RED (1<<8)
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#define LED_GREEN (1<<10)
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#define LED_YELLOW (1<<11)
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#define PP_ISAIOB 0x0020 // IO base address
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#define PP_CS8900_ISAINT 0x0022 // ISA interrupt select
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#define PP_CS8900_ISADMA 0x0024 // ISA Rec DMA channel
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#define PP_ISASOF 0x0026 // ISA DMA offset
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#define PP_DmaFrameCnt 0x0028 // ISA DMA Frame count
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#define PP_DmaByteCnt 0x002A // ISA DMA Byte count
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#define PP_CS8900_ISAMemB 0x002C // Memory base
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#define PP_ISABootBase 0x0030 // Boot Prom base
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#define PP_ISABootMask 0x0034 // Boot Prom Mask
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// EEPROM data and command registers
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#define PP_EECMD 0x0040 // NVR Interface Command register
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#define PP_EEData 0x0042 // NVR Interface Data Register
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// Configuration and control registers
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#define PP_RxCFG 0x0102 // Rx Bus config
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#define PP_RxCTL 0x0104 // Receive Control Register
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#define PP_TxCFG 0x0106 // Transmit Config Register
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#define PP_TxCMD 0x0108 // Transmit Command Register
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#define PP_BufCFG 0x010A // Bus configuration Register
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#define PP_LineCTL 0x0112 // Line Config Register
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#define PP_SelfCTL 0x0114 // Self Command Register
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#define PP_BusCTL 0x0116 // ISA bus control Register
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#define PP_TestCTL 0x0118 // Test Register
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// Status and Event Registers
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#define PP_ISQ 0x0120 // Interrupt Status
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#define PP_RxEvent 0x0124 // Rx Event Register
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#define PP_TxEvent 0x0128 // Tx Event Register
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#define PP_BufEvent 0x012C // Bus Event Register
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#define PP_RxMiss 0x0130 // Receive Miss Count
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#define PP_TxCol 0x0132 // Transmit Collision Count
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#define PP_LineST 0x0134 // Line State Register
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#define PP_SelfST 0x0136 // Self State register
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#define PP_BusST 0x0138 // Bus Status
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#define PP_TDR 0x013C // Time Domain Reflectometry
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// Initiate Transmit Registers
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#define PP_TxCommand 0x0144 // Tx Command
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#define PP_TxLength 0x0146 // Tx Length
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// Adress Filter Registers
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#define PP_LAF 0x0150 // Hash Table
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#define PP_IA 0x0158 // Physical Address Register
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// Frame Location
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#define PP_RxStatus 0x0400 // Receive start of frame
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#define PP_RxLength 0x0402 // Receive Length of frame
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#define PP_RxFrame 0x0404 // Receive frame pointer
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#define PP_TxFrame 0x0A00 // Transmit frame pointer
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// Primary I/O Base Address. If no I/O base is supplied by the user, then this
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// can be used as the default I/O base to access the PacketPage Area.
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#define DEFAULTIOBASE 0x0300
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// PP_RxCFG - Receive Configuration and Interrupt Mask bit definition - Read/write
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#define SKIP_1 0x0040
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#define RX_STREAM_ENBL 0x0080
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#define RX_OK_ENBL 0x0100
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#define RX_DMA_ONLY 0x0200
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#define AUTO_RX_DMA 0x0400
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#define BUFFER_CRC 0x0800
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#define RX_CRC_ERROR_ENBL 0x1000
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#define RX_RUNT_ENBL 0x2000
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#define RX_EXTRA_DATA_ENBL 0x4000
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// PP_RxCTL - Receive Control bit definition - Read/write
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#define RX_IA_HASH_ACCEPT 0x0040
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#define RX_PROM_ACCEPT 0x0080
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#define RX_OK_ACCEPT 0x0100
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#define RX_MULTCAST_ACCEPT 0x0200
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#define RX_IA_ACCEPT 0x0400
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#define RX_BROADCAST_ACCEPT 0x0800
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#define RX_BAD_CRC_ACCEPT 0x1000
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#define RX_RUNT_ACCEPT 0x2000
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#define RX_EXTRA_DATA_ACCEPT 0x4000
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// PP_TxCFG - Transmit Configuration Interrupt Mask bit definition - Read/write
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#define TX_LOST_CRS_ENBL 0x0040
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#define TX_SQE_ERROR_ENBL 0x0080
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#define TX_OK_ENBL 0x0100
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#define TX_LATE_COL_ENBL 0x0200
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#define TX_JBR_ENBL 0x0400
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#define TX_ANY_COL_ENBL 0x0800
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#define TX_16_COL_ENBL 0x8000
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// PP_TxCMD - Transmit Command bit definition - Read-only and
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// PP_TxCommand - Write-only
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#define TX_START_5_BYTES 0x0000
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#define TX_START_381_BYTES 0x0040
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#define TX_START_1021_BYTES 0x0080
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#define TX_START_ALL_BYTES 0x00C0
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#define TX_FORCE 0x0100
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#define TX_ONE_COL 0x0200
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#define TX_NO_CRC 0x1000
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#define TX_RUNT 0x2000
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// PP_BufCFG - Buffer Configuration Interrupt Mask bit definition - Read/write
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#define GENERATE_SW_INTERRUPT 0x0040
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#define RX_DMA_ENBL 0x0080
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#define READY_FOR_TX_ENBL 0x0100
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#define TX_UNDERRUN_ENBL 0x0200
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#define RX_MISS_ENBL 0x0400
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#define RX_128_BYTE_ENBL 0x0800
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#define TX_COL_COUNT_OVRFLOW_ENBL 0x1000
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#define RX_MISS_COUNT_OVRFLOW_ENBL 0x2000
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#define RX_DEST_MATCH_ENBL 0x8000
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// PP_LineCTL - Line Control bit definition - Read/write
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#define SERIAL_RX_ON 0x0040
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#define SERIAL_TX_ON 0x0080
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#define AUI_ONLY 0x0100
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#define AUTO_AUI_10BASET 0x0200
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#define MODIFIED_BACKOFF 0x0800
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#define NO_AUTO_POLARITY 0x1000
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#define TWO_PART_DEFDIS 0x2000
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#define LOW_RX_SQUELCH 0x4000
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// PP_SelfCTL - Software Self Control bit definition - Read/write
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#define POWER_ON_RESET 0x0040
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#define SW_STOP 0x0100
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#define SLEEP_ON 0x0200
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#define AUTO_WAKEUP 0x0400
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#define HCB0_ENBL 0x1000
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#define HCB1_ENBL 0x2000
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#define HCB0 0x4000
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#define HCB1 0x8000
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// PP_BusCTL - ISA Bus Control bit definition - Read/write
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#define RESET_RX_DMA 0x0040
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#define MEMORY_ON 0x0400
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#define DMA_BURST_MODE 0x0800
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#define IO_CHANNEL_READY_ON 0x1000
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#define RX_DMA_SIZE_64K 0x2000
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#define ENABLE_IRQ 0x8000
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// PP_TestCTL - Test Control bit definition - Read/write
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#define LINK_OFF 0x0080
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#define ENDEC_LOOPBACK 0x0200
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#define AUI_LOOPBACK 0x0400
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#define BACKOFF_OFF 0x0800
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#define FDX_8900 0x4000
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// PP_RxEvent - Receive Event Bit definition - Read-only
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#define RX_IA_HASHED 0x0040
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#define RX_DRIBBLE 0x0080
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#define RX_OK 0x0100
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#define RX_HASHED 0x0200
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#define RX_IA 0x0400
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#define RX_BROADCAST 0x0800
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#define RX_CRC_ERROR 0x1000
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#define RX_RUNT 0x2000
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#define RX_EXTRA_DATA 0x4000
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#define HASH_INDEX_MASK 0xFC00 // Hash-Table Index Mask (6 Bit)
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// PP_TxEvent - Transmit Event Bit definition - Read-only
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#define TX_LOST_CRS 0x0040
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#define TX_SQE_ERROR 0x0080
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#define TX_OK 0x0100
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#define TX_LATE_COL 0x0200
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#define TX_JBR 0x0400
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#define TX_16_COL 0x8000
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#define TX_COL_COUNT_MASK 0x7800
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// PP_BufEvent - Buffer Event Bit definition - Read-only
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#define SW_INTERRUPT 0x0040
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#define RX_DMA 0x0080
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#define READY_FOR_TX 0x0100
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#define TX_UNDERRUN 0x0200
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#define RX_MISS 0x0400
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#define RX_128_BYTE 0x0800
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#define TX_COL_OVRFLW 0x1000
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#define RX_MISS_OVRFLW 0x2000
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#define RX_DEST_MATCH 0x8000
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// PP_LineST - Ethernet Line Status bit definition - Read-only
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#define LINK_OK 0x0080
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#define AUI_ON 0x0100
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#define TENBASET_ON 0x0200
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#define POLARITY_OK 0x1000
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#define CRS_OK 0x4000
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// PP_SelfST - Chip Software Status bit definition
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#define ACTIVE_33V 0x0040
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#define INIT_DONE 0x0080
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#define SI_BUSY 0x0100
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#define EEPROM_PRESENT 0x0200
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#define EEPROM_OK 0x0400
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#define EL_PRESENT 0x0800
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#define EE_SIZE_64 0x1000
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// PP_BusST - ISA Bus Status bit definition
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#define TX_BID_ERROR 0x0080
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#define READY_FOR_TX_NOW 0x0100
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// The following block defines the ISQ event types
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#define ISQ_RX_EVENT 0x0004
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#define ISQ_TX_EVENT 0x0008
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#define ISQ_BUFFER_EVENT 0x000C
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#define ISQ_RX_MISS_EVENT 0x0010
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#define ISQ_TX_COL_EVENT 0x0012
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#define ISQ_EVENT_MASK 0x003F // ISQ mask to find out type of event
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// Ports for I/O-Mode
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#define RX_FRAME_PORT 0x0000
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#define TX_FRAME_PORT 0x0000
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#define TX_CMD_PORT 0x0004
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#define TX_LEN_PORT 0x0006
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#define ISQ_PORT 0x0008
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#define ADD_PORT 0x000A
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#define DATA_PORT 0x000C
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#define AUTOINCREMENT 0x8000 // Bit mask to set Bit-15 for autoincrement
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// EEProm Commands
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#define EEPROM_WRITE_EN 0x00F0
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#define EEPROM_WRITE_DIS 0x0000
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#define EEPROM_WRITE_CMD 0x0100
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#define EEPROM_READ_CMD 0x0200
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// Receive Header of each packet in receive area of memory for DMA-Mode
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#define RBUF_EVENT_LOW 0x0000 // Low byte of RxEvent
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#define RBUF_EVENT_HIGH 0x0001 // High byte of RxEvent
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#define RBUF_LEN_LOW 0x0002 // Length of received data - low byte
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#define RBUF_LEN_HI 0x0003 // Length of received data - high byte
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#define RBUF_HEAD_LEN 0x0004 // Length of this header
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// typedefs
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typedef struct { // struct to store CS8900's
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unsigned int Addr; // init-sequence
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unsigned int Data;
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} TInitSeq;
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unsigned short ticks;
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static void skip_frame(void);
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const TInitSeq InitSeq[] =
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{
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PP_IA, UIP_ETHADDR0 + (UIP_ETHADDR1 << 8), // set our MAC as Individual Address
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PP_IA + 2, UIP_ETHADDR2 + (UIP_ETHADDR3 << 8),
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PP_IA + 4, UIP_ETHADDR4 + (UIP_ETHADDR5 << 8),
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PP_LineCTL, SERIAL_RX_ON | SERIAL_TX_ON, // configure the Physical Interface
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PP_RxCTL, RX_OK_ACCEPT | RX_IA_ACCEPT | RX_BROADCAST_ACCEPT
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};
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// Writes a word in little-endian byte order to a specified port-address
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void
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cs8900a_write(unsigned addr, unsigned int data)
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{
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GPIO_IODIR |= 0xff << 16; // Data port to output
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GPIO_IOCLR = 0xf << 4; // Put address on bus
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GPIO_IOSET = addr << 4;
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GPIO_IOCLR = 0xff << 16; // Write low order byte to data bus
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GPIO_IOSET = data << 16;
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__asm volatile ( "NOP" );
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GPIO_IOCLR = IOW; // Toggle IOW-signal
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__asm volatile ( "NOP" );
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GPIO_IOSET = IOW;
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__asm volatile ( "NOP" );
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GPIO_IOCLR = 0xf << 4;
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GPIO_IOSET = ((addr | 1) << 4); // And put next address on bus
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GPIO_IOCLR = 0xff << 16; // Write high order byte to data bus
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GPIO_IOSET = data >> 8 << 16;
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__asm volatile ( "NOP" );
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GPIO_IOCLR = IOW; // Toggle IOW-signal
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__asm volatile ( "NOP" );
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GPIO_IOSET = IOW;
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__asm volatile ( "NOP" );
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}
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// Reads a word in little-endian byte order from a specified port-address
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unsigned
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cs8900a_read(unsigned addr)
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{
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unsigned int value;
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GPIO_IODIR &= ~(0xff << 16); // Data port to input
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GPIO_IOCLR = 0xf << 4; // Put address on bus
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GPIO_IOSET = addr << 4;
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__asm volatile ( "NOP" );
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GPIO_IOCLR = IOR; // IOR-signal low
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__asm volatile ( "NOP" );
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value = (GPIO_IOPIN >> 16) & 0xff; // get low order byte from data bus
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GPIO_IOSET = IOR;
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GPIO_IOSET = 1 << 4; // IOR high and put next address on bus
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__asm volatile ( "NOP" );
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GPIO_IOCLR = IOR; // IOR-signal low
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__asm volatile ( "NOP" );
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value |= ((GPIO_IOPIN >> 8) & 0xff00); // get high order byte from data bus
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GPIO_IOSET = IOR; // IOR-signal low
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return value;
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}
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// Reads a word in little-endian byte order from a specified port-address
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unsigned
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cs8900a_read_addr_high_first(unsigned addr)
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{
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unsigned int value;
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GPIO_IODIR &= ~(0xff << 16); // Data port to input
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GPIO_IOCLR = 0xf << 4; // Put address on bus
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GPIO_IOSET = (addr+1) << 4;
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__asm volatile ( "NOP" );
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GPIO_IOCLR = IOR; // IOR-signal low
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__asm volatile ( "NOP" );
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value = ((GPIO_IOPIN >> 8) & 0xff00); // get high order byte from data bus
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GPIO_IOSET = IOR; // IOR-signal high
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GPIO_IOCLR = 1 << 4; // Put low address on bus
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__asm volatile ( "NOP" );
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GPIO_IOCLR = IOR; // IOR-signal low
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__asm volatile ( "NOP" );
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value |= (GPIO_IOPIN >> 16) & 0xff; // get low order byte from data bus
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GPIO_IOSET = IOR;
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return value;
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}
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void
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cs8900a_init(void)
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{
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int i;
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// Reset outputs, control lines high
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GPIO_IOSET = IOR | IOW;
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// No LEDs on.
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GPIO_IOSET = LED_RED | LED_YELLOW | LED_GREEN;
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// Port 3 as output (all pins but RS232)
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GPIO_IODIR = ~0U; // everything to output.
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// Reset outputs
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GPIO_IOCLR = 0xff << 16; // clear data outputs
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// Reset the CS8900A
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cs8900a_write(ADD_PORT, PP_SelfCTL);
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cs8900a_write(DATA_PORT, POWER_ON_RESET);
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// Wait until chip-reset is done
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cs8900a_write(ADD_PORT, PP_SelfST);
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while ((cs8900a_read(DATA_PORT) & INIT_DONE) == 0)
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;
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// Configure the CS8900A
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for (i = 0; i < sizeof InitSeq / sizeof (TInitSeq); ++i)
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{
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cs8900a_write(ADD_PORT, InitSeq[i].Addr);
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cs8900a_write(DATA_PORT, InitSeq[i].Data);
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}
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}
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void
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cs8900a_send(void)
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{
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unsigned u;
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GPIO_IOCLR = LED_RED; // Light RED LED when frame starting
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// Transmit command
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cs8900a_write(TX_CMD_PORT, TX_START_ALL_BYTES);
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cs8900a_write(TX_LEN_PORT, uip_len);
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// Maximum number of retries
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u = 8;
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for (;;)
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{
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// Check for avaliable buffer space
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cs8900a_write(ADD_PORT, PP_BusST);
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if (cs8900a_read(DATA_PORT) & READY_FOR_TX_NOW)
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break;
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if (u -- == 0)
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{
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GPIO_IOSET = LED_RED; // Extinguish RED LED on end of frame
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return;
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}
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// No space avaliable, skip a received frame and try again
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skip_frame();
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}
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GPIO_IODIR |= 0xff << 16; // Data port to output
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// Send 40+14=54 bytes of header
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for (u = 0; u < 54; u += 2)
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{
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GPIO_IOCLR = 0xf << 4; // Put address on bus
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GPIO_IOSET = TX_FRAME_PORT << 4;
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GPIO_IOCLR = 0xff << 16; // Write low order byte to data bus
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GPIO_IOSET = uip_buf[u] << 16; // write low order byte to data bus
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__asm volatile ( "NOP" );
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GPIO_IOCLR = IOW; // Toggle IOW-signal
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__asm volatile ( "NOP" );
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GPIO_IOSET = IOW;
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GPIO_IOCLR = 0xf << 4; // Put address on bus
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GPIO_IOSET = (TX_FRAME_PORT | 1) << 4; // and put next address on bus
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GPIO_IOCLR = 0xff << 16; // Write low order byte to data bus
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GPIO_IOSET = uip_buf[u+1] << 16; // write low order byte to data bus
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__asm volatile ( "NOP" );
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GPIO_IOCLR = IOW; // Toggle IOW-signal
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__asm volatile ( "NOP" );
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GPIO_IOSET = IOW;
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}
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if (uip_len <= 54)
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{
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GPIO_IOSET = LED_RED; // Extinguish RED LED on end of frame
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return;
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}
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// Send remainder of packet, the application data
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uip_len -= 54;
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for (u = 0; u < uip_len; u += 2)
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{
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GPIO_IOCLR = 0xf << 4; // Put address on bus
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GPIO_IOSET = TX_FRAME_PORT << 4;
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GPIO_IOCLR = 0xff << 16; // Write low order byte to data bus
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GPIO_IOSET = uip_appdata[u] << 16; // write low order byte to data bus
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__asm volatile ( "NOP" );
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GPIO_IOCLR = IOW; // Toggle IOW-signal
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__asm volatile ( "NOP" );
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GPIO_IOSET = IOW;
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GPIO_IOCLR = 0xf << 4; // Put address on bus
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GPIO_IOSET = (TX_FRAME_PORT | 1) << 4; // and put next address on bus
|
|
|
|
GPIO_IOCLR = 0xff << 16; // Write low order byte to data bus
|
|
GPIO_IOSET = uip_appdata[u+1] << 16; // write low order byte to data bus
|
|
|
|
__asm volatile ( "NOP" );
|
|
GPIO_IOCLR = IOW; // Toggle IOW-signal
|
|
__asm volatile ( "NOP" );
|
|
GPIO_IOSET = IOW;
|
|
}
|
|
|
|
GPIO_IOSET = LED_RED; // Extinguish RED LED on end of frame
|
|
}
|
|
|
|
static void
|
|
skip_frame(void)
|
|
{
|
|
// No space avaliable, skip a received frame and try again
|
|
cs8900a_write(ADD_PORT, PP_RxCFG);
|
|
cs8900a_write(DATA_PORT, cs8900a_read(DATA_PORT) | SKIP_1);
|
|
}
|
|
|
|
u8_t
|
|
cs8900a_poll(void)
|
|
{
|
|
u16_t len, u;
|
|
|
|
// Check receiver event register to see if there are any valid frames avaliable
|
|
cs8900a_write(ADD_PORT, PP_RxEvent);
|
|
if ((cs8900a_read(DATA_PORT) & 0xd00) == 0)
|
|
return 0;
|
|
|
|
GPIO_IOCLR = LED_GREEN; // Light GREED LED when frame coming in.
|
|
|
|
// Read receiver status and discard it.
|
|
cs8900a_read_addr_high_first(RX_FRAME_PORT);
|
|
|
|
// Read frame length
|
|
len = cs8900a_read_addr_high_first(RX_FRAME_PORT);
|
|
|
|
// If the frame is too big to handle, throw it away
|
|
if (len > UIP_BUFSIZE)
|
|
{
|
|
skip_frame();
|
|
return 0;
|
|
}
|
|
|
|
// Data port to input
|
|
GPIO_IODIR &= ~(0xff << 16);
|
|
|
|
GPIO_IOCLR = 0xf << 4; // put address on bus
|
|
GPIO_IOSET = RX_FRAME_PORT << 4;
|
|
|
|
// Read bytes into uip_buf
|
|
u = 0;
|
|
while (u < len)
|
|
{
|
|
GPIO_IOCLR = 1 << 4; // put address on bus
|
|
|
|
GPIO_IOCLR = IOR; // IOR-signal low
|
|
uip_buf[u] = GPIO_IOPIN >> 16; // get high order byte from data bus
|
|
__asm volatile ( "NOP" );
|
|
GPIO_IOSET = IOR; // IOR-signal high
|
|
|
|
GPIO_IOSET = 1 << 4; // put address on bus
|
|
|
|
GPIO_IOCLR = IOR; // IOR-signal low
|
|
__asm volatile ( "NOP" );
|
|
uip_buf[u+1] = GPIO_IOPIN >> 16; // get high order byte from data bus
|
|
GPIO_IOSET = IOR; // IOR-signal high
|
|
u += 2;
|
|
}
|
|
|
|
GPIO_IOSET = LED_GREEN; // Extinguish GREED LED when frame finished.
|
|
return len;
|
|
}
|
|
|