BCM2835手册

Table of Contents 1 Introduction 4 1.1 Overview 4 1.2 Address map 4 1.2.1 Diagrammatic overview 4 1.2.2 ARM virtual addresses (standard Linux kernel only) 6 1.2.3 ARM physical addresses 6 1.2.4 Bus addresses 6 1.3 Peripheral access precautions for correct memory ordering 7 2 Auxiliaries: UART1 & SPI1, SPI2 8 2.1 Overview 8 2.1.1 AUX registers 9 2.2 Mini UART 10 2.2.1 Mini UART implementation details. 11 2.2.2 Mini UART register details. 11 2.3 Universal SPI Master (2x) 20 2.3.1 SPI implementation details 20 2.3.2 Interrupts 21 2.3.3 Long bit streams 21 2.3.4 SPI register details. 22 3 BSC 28 3.1 Introduction 28 3.2 Register View 28 3.3 10 Bit Addressing 36 4 DMA Controller 38 4.1 Overview 38 4.2 DMA Controller Registers 39 4.2.1 DMA Channel Register Address Map 40 4.3 AXI Bursts 63 4.4 Error Handling 63 4.5 DMA LITE Engines 63 5 External Mass Media Controller 65 o Introduction 65 o Registers 66 6 General Purpose I/O (GPIO) 89 6.1 Register View 90 6.2 Alternative Function Assignments 102 6.3 General Purpose GPIO Clocks 105 7 Interrupts 109 7.1 Introduction 109 7.2 Interrupt pending. 110 7.3 Fast Interrupt (FIQ). 110 7.4 Interrupt priority. 110 7.5 Registers 112 8 PCM / I2S Audio 119 8.1 Block Diagram 120 8.2 Typical Timing 120 8.3 Operation 121 8.4 Software Operation 122 8.4.1 Operating in Polled mode 122 8.4.2 Operating in Interrupt mode 123 8.4.3 DMA 123 8.5 Error Handling. 123 8.6 PDM Input Mode Operation 124 8.7 GRAY Code Input Mode Operation 124 8.8 PCM Register Map 125 9 Pulse Width Modulator 138 9.1 Overview 138 9.2 Block Diagram 138 9.3 PWM Implementation 139 9.4 Modes of Operation 139 9.5 Quick Reference 140 9.6 Control and Status Registers 141 10 SPI 148 10.1 Introduction 148 10.2 SPI Master Mode 148 10.2.1 Standard mode 148 10.2.2 Bidirectional mode 149 10.3 LoSSI mode 150 10.3.1 Command write 150 10.3.2 Parameter write 150 10.3.3 Byte read commands 151 10.3.4 24bit read command 151 10.3.5 32bit read command 151 10.4 Block Diagram 152 10.5 SPI Register Map 152 10.6 Software Operation 158 10.6.1 Polled 158 10.6.2 Interrupt 158 10.6.3 DMA 158 10.6.4 Notes 159 11 SPI/BSC SLAVE 160 11.1 Introduction 160 11.2 Registers 160 12 System Timer 172 12.1 System Timer Registers 172 13 UART 175 13.1 Variations from the 16C650 UART 175 13.2 Primary UART Inputs and Outputs 176 13.3 UART Interrupts 176 13.4 Register View 177 14 Timer (ARM side) 196 14.1 Introduction 196 14.2 Timer Registers: 196 15 USB 200 15.1 Configuration 200 15.2 Extra / Adapted registers. 202