(原創) 如何在DE2執行Checksum Master範例? (IC Design) (DE2) (Quartus II) (Nios II) (SOPC Builder)

Abstract
Checksum Master為Quartus II 7.2 Handbook Vol:4中，示範使用Component Editor將user logic包成component後，並撰寫software driver的範例，但手冊中的程式和步驟都無法在DE2上順利執行，本文提出解決的方法。

使用環境 : Quartus II 7.2 SP1 + Nios II 7.2 SP1 + DE2 (Cyclone II EP2C35F627C6)
手冊版本：Quartus II Version 7.2 Handbook Volume4 : SOPC Builder

Introduction
Checksum Master是Altera在Quartus 7.1之後的範例程式，用以取代以前的PWM(pulse width modulator)，PWM只示範了Avalon-MM slave interface，但Checksum Master同時示範了master和slave，且搭配SOPC Builder 7.1之後大改的介面。

不過很不幸的，Altera所附的範例和手冊中的步驟，僅適用於Altera原廠的版子，並不適用於DE2，經過幾天的搏鬥，總算修改成適用於Quartus 7.2 SP1和DE2的範例。

下載Checksum Master
我將Altera原廠的Checksum Master上傳了，請按此下載altera_avalon_checksum.zip。

原廠Checksum Master範例的問題
1.範例僅適用於Altera原廠的版子，並不適用於DE2。
2.範例中使用onchip memory，不過由於DE2上EP2C35F627C6 FPGA的logic element限制，onchip memory最多只能設定49K左右，但這樣的memory size仍無法執行此範例。

Solution
本文並沒有打算重寫整個tutorial，所以建議先將Quartus II 7.2 Handbook Vol.4 Ch.9 Developing Components for SOPC Builder瀏覽一次，在此只將與手冊中不適用於DE2之處列出。

1.使用DE2的reference design
在手冊中的P.9-9頁，Altera建議我們使用<Nios EDS install path>/examples/<verilog or vhdl>/<board version>/standard 目錄下的硬體，由於DE2用的是EP2C35F627C6這顆晶片，直覺會選Cyclone II的niosII_cycloneII_2c35這塊版子，但可惜這是Altera原廠的版子，並非DE2，若選擇這塊版子，Quartus II連編譯都不會過。

請在此下載DE2的reference design
http://www.terasic.com/downloads/cd-rom/de2/
根據你DE2的型號和使用Quartus II的版本，下載適當的DE2_System版本。

若你使用的是Quartus II 7.2，則建議下載Quartus II 7.1的版本，畢竟Quartus II 7.1大改，7.2和7.1較接近，遇到的問題會較少。

以我的狀況，是使用DE2_System_1.4b.zip這個版本。

DE2的Nios II reference design在壓縮檔內的
\DE2_demonstrations\SOPC_Builder\Reference_Design\DE2_NIOS\

將這個目錄複製到任何位置，並更改目錄名稱為checksum_master_onchip，使用Quartus II開起DE2_NIOS.qpf。

2.使用on-chip memory
在Quartus II Vol.4 Ch.9 P.9-24，有一段話，特別強調須使用on-chip memory。

The test program uses an on-chip memory peripheral called onchip_ram. If your SOPC Builder system does not have an on-chip memory you should add an on-chip memory to the design. The test program requires that the name of the on-chip RAM and the component name used in the test program match. Connect the on-chip RAM to the Nios II data master.

當將on-chip memory加入DE2_NIOS後，儘管只是預設的4K，在Quartus II編譯也會有以下錯誤訊息：

Error : Cannot place all RAM cells in design

Error : Can't fit design in device

原因是on-chip memory相當浪費logic element count，FPGA已經塞不下了，或許你會說，『DE2的Nios II reference design放了很多我沒用到的component，將其刪除就可放on-chip memory了』，聽起來是個可行方案，我試著將component刪到只剩下最簡，Nios II CPU也改成最簡單的Nios II/e，如此可將on-chip memory擴大到49K，也依照了手冊的步驟加入了user logic component，最後SOPC Builder如下：

DE2 reference design完整code如下
DE2_NIOS.v

// --------------------------------------------------------------------

// Permission:

// Terasic grants permission to use and modify this code for use

// in synthesis for all Terasic Development Boards and Altera Development

// Kits made by Terasic. Other use of this code, including the selling

// ,duplication, or modification of any portion is strictly prohibited.

// Disclaimer:

// This VHDL/Verilog or C/C++ source code is intended as a design reference

// which illustrates how these types of functions can be implemented.

// It is the user's responsibility to verify their design for

// consistency and functionality through the use of formal

// verification methods. Terasic provides no warranty regarding the use

// or functionality of this code.

// --------------------------------------------------------------------

// Terasic Technologies Inc

// 356 Fu-Shin E. Rd Sec. 1. JhuBei City,

// HsinChu County, Taiwan

// 302

// web: http://www.terasic.com/

// email: support@terasic.com

// --------------------------------------------------------------------

// Major Functions: DE2 NIOS Reference Design

// --------------------------------------------------------------------

// Revision History :

// --------------------------------------------------------------------

// Ver :| Author :| Mod. Date :| Changes Made:

// V2.0 :| Johnny Chen :| 06/07/19 :| Initial Revision

// --------------------------------------------------------------------

module DE2_NIOS

(

//////////////////// Clock Input ////////////////////

CLOCK_27, // On Board 27 MHz

CLOCK_50, // On Board 50 MHz

EXT_CLOCK, // External Clock

//////////////////// Push Button ////////////////////

KEY, // Pushbutton[3:0]

//////////////////// DPDT Switch ////////////////////

SW, // Toggle Switch[17:0]

//////////////////// 7-SEG Dispaly ////////////////////

HEX0, // Seven Segment Digit 0

HEX1, // Seven Segment Digit 1

HEX2, // Seven Segment Digit 2

HEX3, // Seven Segment Digit 3

HEX4, // Seven Segment Digit 4

HEX5, // Seven Segment Digit 5

HEX6, // Seven Segment Digit 6

HEX7, // Seven Segment Digit 7

//////////////////////// LED ////////////////////////

LEDG, // LED Green[8:0]

LEDR, // LED Red[17:0]

//////////////////////// UART ////////////////////////

UART_TXD, // UART Transmitter

UART_RXD, // UART Receiver

//////////////////////// IRDA ////////////////////////

IRDA_TXD, // IRDA Transmitter

IRDA_RXD, // IRDA Receiver

///////////////////// SDRAM Interface ////////////////

DRAM_DQ, // SDRAM Data bus 16 Bits

DRAM_ADDR, // SDRAM Address bus 12 Bits

DRAM_LDQM, // SDRAM Low-byte Data Mask

DRAM_UDQM, // SDRAM High-byte Data Mask

DRAM_WE_N, // SDRAM Write Enable

DRAM_CAS_N, // SDRAM Column Address Strobe

DRAM_RAS_N, // SDRAM Row Address Strobe

DRAM_CS_N, // SDRAM Chip Select

DRAM_BA_0, // SDRAM Bank Address 0

DRAM_BA_1, // SDRAM Bank Address 1

DRAM_CLK, // SDRAM Clock

DRAM_CKE, // SDRAM Clock Enable

//////////////////// Flash Interface ////////////////

FL_DQ, // FLASH Data bus 8 Bits

FL_ADDR, // FLASH Address bus 20 Bits

FL_WE_N, // FLASH Write Enable

FL_RST_N, // FLASH Reset

FL_OE_N, // FLASH Output Enable

FL_CE_N, // FLASH Chip Enable

//////////////////// SRAM Interface ////////////////

SRAM_DQ, // SRAM Data bus 16 Bits

SRAM_ADDR, // SRAM Address bus 18 Bits

SRAM_UB_N, // SRAM High-byte Data Mask

SRAM_LB_N, // SRAM Low-byte Data Mask

SRAM_WE_N, // SRAM Write Enable

SRAM_CE_N, // SRAM Chip Enable

SRAM_OE_N, // SRAM Output Enable

//////////////////// ISP1362 Interface ////////////////

OTG_DATA, // ISP1362 Data bus 16 Bits

OTG_ADDR, // ISP1362 Address 2 Bits

OTG_CS_N, // ISP1362 Chip Select

OTG_RD_N, // ISP1362 Write

OTG_WR_N, // ISP1362 Read

OTG_RST_N, // ISP1362 Reset

OTG_FSPEED, // USB Full Speed, 0 = Enable, Z = Disable

OTG_LSPEED, // USB Low Speed, 0 = Enable, Z = Disable

OTG_INT0, // ISP1362 Interrupt 0

OTG_INT1, // ISP1362 Interrupt 1

OTG_DREQ0, // ISP1362 DMA Request 0

OTG_DREQ1, // ISP1362 DMA Request 1

OTG_DACK0_N, // ISP1362 DMA Acknowledge 0

OTG_DACK1_N, // ISP1362 DMA Acknowledge 1

//////////////////// LCD Module 16X2 ////////////////

LCD_ON, // LCD Power ON/OFF

LCD_BLON, // LCD Back Light ON/OFF

LCD_RW, // LCD Read/Write Select, 0 = Write, 1 = Read

LCD_EN, // LCD Enable

LCD_RS, // LCD Command/Data Select, 0 = Command, 1 = Data

LCD_DATA, // LCD Data bus 8 bits

//////////////////// SD_Card Interface ////////////////

SD_DAT, // SD Card Data

SD_DAT3, // SD Card Data 3

SD_CMD, // SD Card Command Signal

SD_CLK, // SD Card Clock

//////////////////// USB JTAG link ////////////////////

TDI, // CPLD -> FPGA (Data in)

TCK, // CPLD -> FPGA (Clock)

TCS, // CPLD -> FPGA (CS)

TDO, // FPGA -> CPLD (Data out)

//////////////////// I2C ////////////////////////////

I2C_SDAT, // I2C Data

I2C_SCLK, // I2C Clock

//////////////////// PS2 ////////////////////////////

PS2_DAT, // PS2 Data

PS2_CLK, // PS2 Clock

//////////////////// VGA ////////////////////////////

VGA_CLK, // VGA Clock

VGA_HS, // VGA H_SYNC

VGA_VS, // VGA V_SYNC

VGA_BLANK, // VGA BLANK

VGA_SYNC, // VGA SYNC

VGA_R, // VGA Red[9:0]

VGA_G, // VGA Green[9:0]

VGA_B, // VGA Blue[9:0]

//////////// Ethernet Interface ////////////////////////

ENET_DATA, // DM9000A DATA bus 16Bits

ENET_CMD, // DM9000A Command/Data Select, 0 = Command, 1 = Data

ENET_CS_N, // DM9000A Chip Select

ENET_WR_N, // DM9000A Write

ENET_RD_N, // DM9000A Read

ENET_RST_N, // DM9000A Reset

ENET_INT, // DM9000A Interrupt

ENET_CLK, // DM9000A Clock 25 MHz

//////////////// Audio CODEC ////////////////////////

AUD_ADCLRCK, // Audio CODEC ADC LR Clock

AUD_ADCDAT, // Audio CODEC ADC Data

AUD_DACLRCK, // Audio CODEC DAC LR Clock

AUD_DACDAT, // Audio CODEC DAC Data

AUD_BCLK, // Audio CODEC Bit-Stream Clock

AUD_XCK, // Audio CODEC Chip Clock

//////////////// TV Decoder ////////////////////////

TD_DATA, // TV Decoder Data bus 8 bits

TD_HS, // TV Decoder H_SYNC

TD_VS, // TV Decoder V_SYNC

TD_RESET, // TV Decoder Reset

//////////////////// GPIO ////////////////////////////

GPIO_0, // GPIO Connection 0

GPIO_1 // GPIO Connection 1

);

//////////////////////// Clock Input ////////////////////////

input CLOCK_27; // On Board 27 MHz

input CLOCK_50; // On Board 50 MHz

input EXT_CLOCK; // External Clock

//////////////////////// Push Button ////////////////////////

input [3:0] KEY; // Pushbutton[3:0]

//////////////////////// DPDT Switch ////////////////////////

input [17:0] SW; // Toggle Switch[17:0]

//////////////////////// 7-SEG Display ////////////////////////

output [6:0] HEX0; // Seven Segment Digit 0

output [6:0] HEX1; // Seven Segment Digit 1

output [6:0] HEX2; // Seven Segment Digit 2

output [6:0] HEX3; // Seven Segment Digit 3

output [6:0] HEX4; // Seven Segment Digit 4

output [6:0] HEX5; // Seven Segment Digit 5

output [6:0] HEX6; // Seven Segment Digit 6

output [6:0] HEX7; // Seven Segment Digit 7

//////////////////////////// LED ////////////////////////////

output [8:0] LEDG; // LED Green[8:0]

output [17:0] LEDR; // LED Red[17:0]

//////////////////////////// UART ////////////////////////////

output UART_TXD; // UART Transmitter

input UART_RXD; // UART Receiver

//////////////////////////// IRDA ////////////////////////////

output IRDA_TXD; // IRDA Transmitter

input IRDA_RXD; // IRDA Receiver

/////////////////////// SDRAM Interface ////////////////////////

inout [15:0] DRAM_DQ; // SDRAM Data bus 16 Bits

output [11:0] DRAM_ADDR; // SDRAM Address bus 12 Bits

output DRAM_LDQM; // SDRAM Low-byte Data Mask

output DRAM_UDQM; // SDRAM High-byte Data Mask

output DRAM_WE_N; // SDRAM Write Enable

output DRAM_CAS_N; // SDRAM Column Address Strobe

output DRAM_RAS_N; // SDRAM Row Address Strobe

output DRAM_CS_N; // SDRAM Chip Select

output DRAM_BA_0; // SDRAM Bank Address 0

output DRAM_BA_1; // SDRAM Bank Address 0

output DRAM_CLK; // SDRAM Clock

output DRAM_CKE; // SDRAM Clock Enable

//////////////////////// Flash Interface ////////////////////////

inout [7:0] FL_DQ; // FLASH Data bus 8 Bits

output [21:0] FL_ADDR; // FLASH Address bus 22 Bits

output FL_WE_N; // FLASH Write Enable

output FL_RST_N; // FLASH Reset

output FL_OE_N; // FLASH Output Enable

output FL_CE_N; // FLASH Chip Enable

//////////////////////// SRAM Interface ////////////////////////

inout [15:0] SRAM_DQ; // SRAM Data bus 16 Bits

output [17:0] SRAM_ADDR; // SRAM Address bus 18 Bits

output SRAM_UB_N; // SRAM Low-byte Data Mask

output SRAM_LB_N; // SRAM High-byte Data Mask

output SRAM_WE_N; // SRAM Write Enable

output SRAM_CE_N; // SRAM Chip Enable

output SRAM_OE_N; // SRAM Output Enable

//////////////////// ISP1362 Interface ////////////////////////

inout [15:0] OTG_DATA; // ISP1362 Data bus 16 Bits

output [1:0] OTG_ADDR; // ISP1362 Address 2 Bits

output OTG_CS_N; // ISP1362 Chip Select

output OTG_RD_N; // ISP1362 Write

output OTG_WR_N; // ISP1362 Read

output OTG_RST_N; // ISP1362 Reset

output OTG_FSPEED; // USB Full Speed, 0 = Enable, Z = Disable

output OTG_LSPEED; // USB Low Speed, 0 = Enable, Z = Disable

input OTG_INT0; // ISP1362 Interrupt 0

input OTG_INT1; // ISP1362 Interrupt 1

input OTG_DREQ0; // ISP1362 DMA Request 0

input OTG_DREQ1; // ISP1362 DMA Request 1

output OTG_DACK0_N; // ISP1362 DMA Acknowledge 0

output OTG_DACK1_N; // ISP1362 DMA Acknowledge 1

//////////////////// LCD Module 16X2 ////////////////////////////

inout [7:0] LCD_DATA; // LCD Data bus 8 bits

output LCD_ON; // LCD Power ON/OFF

output LCD_BLON; // LCD Back Light ON/OFF

output LCD_RW; // LCD Read/Write Select, 0 = Write, 1 = Read

output LCD_EN; // LCD Enable

output LCD_RS; // LCD Command/Data Select, 0 = Command, 1 = Data

//////////////////// SD Card Interface ////////////////////////

inout SD_DAT; // SD Card Data

inout SD_DAT3; // SD Card Data 3

inout SD_CMD; // SD Card Command Signal

output SD_CLK; // SD Card Clock

//////////////////////// I2C ////////////////////////////////

inout I2C_SDAT; // I2C Data

output I2C_SCLK; // I2C Clock

//////////////////////// PS2 ////////////////////////////////

input PS2_DAT; // PS2 Data

input PS2_CLK; // PS2 Clock

//////////////////// USB JTAG link ////////////////////////////

input TDI; // CPLD -> FPGA (data in)

input TCK; // CPLD -> FPGA (clk)

input TCS; // CPLD -> FPGA (CS)

output TDO; // FPGA -> CPLD (data out)

//////////////////////// VGA ////////////////////////////

output VGA_CLK; // VGA Clock

output VGA_HS; // VGA H_SYNC

output VGA_VS; // VGA V_SYNC

output VGA_BLANK; // VGA BLANK

output VGA_SYNC; // VGA SYNC

output [9:0] VGA_R; // VGA Red[9:0]

output [9:0] VGA_G; // VGA Green[9:0]

output [9:0] VGA_B; // VGA Blue[9:0]

//////////////// Ethernet Interface ////////////////////////////

inout [15:0] ENET_DATA; // DM9000A DATA bus 16Bits

output ENET_CMD; // DM9000A Command/Data Select, 0 = Command, 1 = Data

output ENET_CS_N; // DM9000A Chip Select

output ENET_WR_N; // DM9000A Write

output ENET_RD_N; // DM9000A Read

output ENET_RST_N; // DM9000A Reset

input ENET_INT; // DM9000A Interrupt

output ENET_CLK; // DM9000A Clock 25 MHz

//////////////////// Audio CODEC ////////////////////////////

inout AUD_ADCLRCK; // Audio CODEC ADC LR Clock

input AUD_ADCDAT; // Audio CODEC ADC Data

inout AUD_DACLRCK; // Audio CODEC DAC LR Clock

output AUD_DACDAT; // Audio CODEC DAC Data

inout AUD_BCLK; // Audio CODEC Bit-Stream Clock

output AUD_XCK; // Audio CODEC Chip Clock

//////////////////// TV Devoder ////////////////////////////

input [7:0] TD_DATA; // TV Decoder Data bus 8 bits

input TD_HS; // TV Decoder H_SYNC

input TD_VS; // TV Decoder V_SYNC

output TD_RESET; // TV Decoder Reset

//////////////////////// GPIO ////////////////////////////////

inout [35:0] GPIO_0; // GPIO Connection 0

inout [35:0] GPIO_1; // GPIO Connection 1

wire CPU_CLK;

wire CPU_RESET;

wire CLK_18_4;

wire CLK_25;

// Flash

assign FL_RST_N = 1'b1;

// 16*2 LCD Module

assign LCD_ON = 1'b1; // LCD ON

assign LCD_BLON = 1'b1; // LCD Back Light

// All inout port turn to tri-state

assign SD_DAT = 1'bz;

assign AUD_ADCLRCK = AUD_DACLRCK;

assign GPIO_0 = 36'hzzzzzzzzz;

assign GPIO_1 = 36'hzzzzzzzzz;

// Disable USB speed select

assign OTG_FSPEED = 1'bz;

assign OTG_LSPEED = 1'bz;

// Turn On TV Decoder

assign TD_RESET = 1'b1;

// Set SD Card to SD Mode

assign SD_DAT3 = 1'b1;

Reset_Delay delay1 (.iRST(KEY[0]),.iCLK(CLOCK_50),.oRESET(CPU_RESET));

SDRAM_PLL PLL1 (.inclk0(CLOCK_50),.c0(DRAM_CLK),.c1(CPU_CLK),.c2(CLK_25));

Audio_PLL PLL2 (.areset(!CPU_RESET),.inclk0(CLOCK_27),.c0(CLK_18_4));

system_0 u0 (

// 1) global signals:

.clk(CPU_CLK),

.reset_n(CPU_RESET)

);

I2C_AV_Config u1 ( // Host Side

.iCLK(CLOCK_50),

.iRST_N(KEY[0]),

// I2C Side

.I2C_SCLK(I2C_SCLK),

.I2C_SDAT(I2C_SDAT) );

endmodule

如此修改後，Quartus II可順利編譯，並且用Programmer燒進DE2。

硬體部分解決了，但不代表軟體部分沒問題!!

接著如手冊的步驟，在Nios II EDS 7.2 build project，出現以下錯誤訊息：

**** Build of configuration Debug for project test_checksum ****

make -s all includes

Compiling test_checksum.c

Linking test_checksum.elf

/cygdrive/c/altera/72/nios2eds/bin/nios2-gnutools/H-i686-pc-cygwin/bin/../lib/gcc/nios2-elf/3.4.1/http://www.cnblogs.com/http://www.cnblogs.com/nios2-elf/bin/ld: region onchip_ram is full (test_checksum.elf section .rwdata). Region needs to be 4976 bytes larger.

/cygdrive/c/altera/72/nios2eds/bin/nios2-gnutools/H-i686-pc-cygwin/bin/../lib/gcc/nios2-elf/3.4.1/http://www.cnblogs.com/http://www.cnblogs.com/nios2-elf/bin/ld: section .bss [00010020 -> 00010233] overlaps section .exceptions [00010020 -> 000101c7]

/cygdrive/c/altera/72/nios2eds/bin/nios2-gnutools/H-i686-pc-cygwin/bin/../lib/gcc/nios2-elf/3.4.1/http://www.cnblogs.com/http://www.cnblogs.com/nios2-elf/lib/mno-hw-mul//libc.a(sbrkr.o)(.text+0x14): In function `_sbrk_r':

/build/nios2eds-gnutools-win32-7.2/bin/nios2-gnutools/src/newlib/newlib/libc/reent/sbrkr.c:59: Unable to reach errno (at 0x00010020) from the global pointer (at 0x00025704) because the offset (-87780) is out of the allowed range, -32678 to 32767.

collect2: ld returned 1 exit status

make: *** [test_checksum.elf] Error 1

Build completed in 2.641 seconds

主要是這一句

Region needs to be 4976 bytes larger.

on-chip memory不夠跑了，還需要4K的記憶體!!
但on-chip memory的49K已經是極限了!!

到了這邊，有兩條路可走
1.從軟體解決，想辦法將軟體的code size減少!!
2.從硬體解決，改用SRAM或SDRAM!!

軟體解決
修改System Library Properties選項
將Lightweight device driver API、Reduced device drivers、Small C library打勾，不要選取Support C++，這樣減少所產生的code size，可以節省些記憶體空間。

修改gcc參數
改為release mode和optimize size

如此修改後，可正常Build Project且Run As Hardware執行，結果如下

硬體解決
改用SRAM(或SDRAM)
從軟體解決雖然可以跑了，但並非長遠之道，且on-chip memory非常耗logic element，若日後在加上自己的verilog code，難保on-chip memory還夠用，且DE2上已經有SRAM和SDRAM，實應妥善運用這兩塊記憶體。

由於使用了SRAM，對DE2 reference design就不再做修改，但必須將altera_avalon_checksum_inst的m1(Avalon Master)改接在SRAM上。

軟體部分
由於改用了SRAM，System Library Properties必須改成run在SRAM上。

若直接使用原本的test_checksum.c，執行後會出現以下錯誤訊息。

**** Build of configuration Debug for project blank_project_0 ****

make -s all includes

Compiling test_checksum.c

../test_checksum.c: In function `main':

../test_checksum.c:52: error: `ONCHIP_RAM_BASE' undeclared (first use in this function)

../test_checksum.c:52: error: (Each undeclared identifier is reported only once

../test_checksum.c:52: error: for each function it appears in.)

make: *** [obj/test_checksum.o] Error 1

Build completed in 3.203 seconds

因為硬體沒使用on-chip memory，故register map也沒有ONCHIP_RAM_BASE這個macro，由於我們改用了SRAM，故將macro名稱改為SRAM_0_BASE。

/* base of onchip ram defined in system.h file */
2

/*alt_u8* buf = (alt_u8*) ONCHIP_RAM_BASE; */
3

alt_u8* buf = (alt_u8*)SRAM_0_BASE;

完整的test_checksum.c如下

/******************************************************************************
2

* subject to the License Agreement located at the end of this file below. *
5

*******************************************************************************/
6

/* Simple C program that exercises the altera_avalon_checksum component by
7

* filling a memory buffer with test data and then configuring the
8

* altera_avalon_checksum to read back the data using the IOWR and IORD
9

* to directly write to the register locations as defined in the _regs.h
10

* file
11

*
12

* Version History
13

* BR 04/01/2007 Created
14

* ATJ 04/12/2007 Add additional comments
15

*
16

*/
17

#include <stdio.h>
19

#include <stdlib.h>
20

#include "altera_avalon_checksum_regs.h"
21

#include "system.h"
22

#include <alt_types.h>
23

/* Simple function that sets all contents of a buffer to the specified value. */
26

int set_buf_val( alt_u8* buffer, int length, alt_u8 val )
27

{
28

int ret_code = 0;
29

/* Ok

one byte at a time is not efficient

C'est La Vie! */
31

while (length >= 0)
33

{
34

*(buffer + length) = val;
35

if( *(buffer+length) != val )
36

{
37

ret_code = -1;
38

}
39

length--;
40

}
41

return( ret_code );
42

}
43

/* This program points the checksum component at a small buffer and
45

* computes the checksum.
46

*/
47

int main()
49

{
50

/* Point the buffer at the base of the onchip ram.*/
51

/* base of onchip ram defined in system.h file */
52

/*alt_u8* buf = (alt_u8*) ONCHIP_RAM_BASE; */
53

alt_u8* buf = (alt_u8*)SRAM_0_BASE;
54

/* Set the length small, to start with. */
55

int len = 12;
56

int status;
57

int result;
58

/* Set the buffer to all 0xF0's. */
61

printf( "Writing to test memory. \n");
62

if( (set_buf_val( buf, len, 0xf0 )<0) )
63

{
64

printf( "Error: Could not pre-set buffer at %d.\n", (int) buf );
65

return( -1 );
66

}
67

/* Setup the checksum component. */
69

/* IORD and IOWR macros setup in alter_avalon_checksum_regs.h and io.h */
70

/* Store the address (must be 32-bit word aligned address). */
72

printf( "Writing to address register. \n");
73

//IOWR_ALTERA_AVALON_CHECKSUM_ADDR( ALTERA_AVALON_CHECKSUM_INST_BASE, _RAM_BASE );
74

IOWR_ALTERA_AVALON_CHECKSUM_ADDR( ALTERA_AVALON_CHECKSUM_INST_BASE, SRAM_0_BASE );
75

/* Store the length in bytes (up to a 16-bit value). */
76

printf( "Writing to length register. \n");
77

IOWR_ALTERA_AVALON_CHECKSUM_LENGTH( ALTERA_AVALON_CHECKSUM_INST_BASE, len );
78

/* Tell it to "go". */
79

printf( "Writing to go bit in control register. \n");
80

IOWR_ALTERA_AVALON_CHECKSUM_CTRL( ALTERA_AVALON_CHECKSUM_INST_BASE+ALTERA_AVALON_CHECKSUM_CTRL_GO_OFST,
81

ALTERA_AVALON_CHECKSUM_CTRL_GO_MSK);
82

/* Polling loop waiting for the component to be done. */
83

status = IORD_ALTERA_AVALON_CHECKSUM_STATUS( ALTERA_AVALON_CHECKSUM_INST_BASE );
84

printf( "Polling for DONE bit in status register. . . \n");
86

while( !(status & ALTERA_AVALON_CHECKSUM_STATUS_DONE_MSK) )
87

{
88

status = IORD_ALTERA_AVALON_CHECKSUM_STATUS( ALTERA_AVALON_CHECKSUM_INST_BASE );
89

}
90

printf( "Done bit asserted, exiting polling loop. \n");
91

result = IORD_ALTERA_AVALON_CHECKSUM_RESULT( ALTERA_AVALON_CHECKSUM_INST_BASE );
93

printf( "Done

Result = 0x%x.\n", (int) result );
95

return 0;
97

}
98

最後執行結果

完整程式碼下載
Altera原廠的altera_avalon_checksum.zip
Checksum Master on on-chip memory
Checksum Master on SRAM

Conclusion
凡是Altera原廠的範例，若要用在DE2，尤其是Nios II上，一定得改用DE2的reference design，這是跑不掉的。至於其他的修改，就得見招拆招了，畢竟DE2不是Altera原廠的版子。本文我們看到從軟體減少code size的方法，也看到從硬體從on-chip memory改用SRAM的方法。

posted on 2008-01-04 20:54 真 OO无双阅读(9104) 评论(17) 编辑收藏举报

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(原創) 如何在DE2執行Checksum Master範例? (IC Design) (DE2) (Quartus II) (Nios II) (SOPC Builder)

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