(转）如何以32 bit的方式存取SDRAM?
全文地址：http://www.cnblogs.com/oomusou/archive/2008/11/25/sdram32.html
Abstract
在DE2因為只有一顆16 bit的SDRAM，儘管Nios II CPU是32 bit，存取SDRAM時必須透過Dyanamic Bus Sizing機制，花2個clk才能將32 bit資料讀取/寫入SDRAM；但DE2-70有2顆16 bit SDRAM，是否使用雙通道的方式，將這2顆16 bit SDRAM看成1顆32 bit SDRAM使用呢?
Introduction
這個做法是Mithril所提供，感謝Mithril無私的分享，我只是加以整理。
使用環境：Quartus II 8.1 + DE2-70 (Cyclone II EP2C70F896C6N)
在(原創) 哪裡有DE2-70的Nios II reference design可以參考? (SOC) (DE2-70) (Nios II) (SOPC Builder)與DE2-70 CD中提供的範例，如DE2_70_NET、DE2_70_NIOS_DEVICE_LED、DE2_70_NIOS_HOST_MOUSE_VGA、DE2_70_SD_Card_Audio_Player中，都是使用2個16 bit SDRAM controller，各自對應到2顆SDRAM。
不過可惜的是，SDRAM Controller的Data width只有16 bit，而Nios II CPU與其他ip都是32 bit，由於Data width不同，Avalon bus會啟動Dynamic Bus Sizing機制，2個clk才能完成32 bit傳輸。
將2顆16 bit SDRAM當成1顆32 bit SDRAM使用
Step 1：
只留下1個SDRAM controller即可
Step 2：
Data width改成32 bit，其餘不用改
注意結果仍為64MB，顯然沒有因為只用了一個SDRAM controller而少抓memory size。
Step 3：
修改top module
DE2_70_NIOS.v / Verilog
1 /*
2 (C) OOMusou 2008 http://oomusou.cnblogs.com
3
4 Filename : DE2_70_NIOS.v
5 Compiler : Quartus II 8.1
6 Description : DE2_70_NIOS reference design 1.1
7 Release : 11/25/2008 1.0
8 */
9
10 module DE2_70_NIOS (
11 input iCLK_28, // 28.63636 MHz
12 input iCLK_50, // 50 MHz
13 input iCLK_50_2, // 50 MHz
14 input iCLK_50_3, // 50 MHz
15 input iCLK_50_4, // 50 MHz
16 input iEXT_CLOCK, // External Clock
17 ////////////////////////////// Push Button ////////////////////////
18 input [3:0] iKEY, // Pushbutton[3:0]
19 ////////////////////////////// DPDT Switch ////////////////////////
20 input [17:0] iSW, // Toggle Switch[17:0]
21 ////////////////////////////// 7-SEG Dispaly ////////////////////////
22 output [6:0] oHEX0_D, // Seven Segment Digit 0
23 output oHEX0_DP, // Seven Segment Digit 0 decimal point
24 output [6:0] oHEX1_D, // Seven Segment Digit 1
25 output oHEX1_DP, // Seven Segment Digit 1 decimal point
26 output [6:0] oHEX2_D, // Seven Segment Digit 2
27 output oHEX2_DP, // Seven Segment Digit 2 decimal point
28 output [6:0] oHEX3_D, // Seven Segment Digit 3
29 output oHEX3_DP, // Seven Segment Digit 3 decimal point
30 output [6:0] oHEX4_D, // Seven Segment Digit 4
31 output oHEX4_DP, // Seven Segment Digit 4 decimal point
32 output [6:0] oHEX5_D, // Seven Segment Digit 5
33 output oHEX5_DP, // Seven Segment Digit 5 decimal point
34 output [6:0] oHEX6_D, // Seven Segment Digit 6
35 output oHEX6_DP, // Seven Segment Digit 6 decimal point
36 output [6:0] oHEX7_D, // Seven Segment Digit 7
37 output oHEX7_DP, // Seven Segment Digit 7 decimal point
38 //////////////////////////////// LED ////////////////////////////
39 output [8:0] oLEDG, // LED Green[8:0]
40 output [17:0] oLEDR, // LED Red[17:0]
41 //////////////////////////////// UART ////////////////////////////
42 output oUART_TXD, // UART Transmitter
43 input iUART_RXD, // UART Receiver
44 output oUART_CTS, // UART Clear To Send
45 input iUART_RTS, // UART Requst To Send
46 //////////////////////////////// IRDA ////////////////////////////
47 output oIRDA_TXD, // IRDA Transmitter
48 input iIRDA_RXD, // IRDA Receiver
49 //////////////////////////////// SDRAM Interface ////////////////////////
50 inout [31:0] DRAM_DQ, // SDRAM Data bus 32 Bits
51 output [12:0] oDRAM0_A, // SDRAM0 Address bus 12 Bits
52 output [12:0] oDRAM1_A, // SDRAM1 Address bus 12 Bits
53 output oDRAM0_LDQM0, // SDRAM0 Low-byte Data Mask
54 output oDRAM1_LDQM0, // SDRAM1 Low-byte Data Mask
55 output oDRAM0_UDQM1, // SDRAM0 High-byte Data Mask
56 output oDRAM1_UDQM1, // SDRAM1 High-byte Data Mask
57 output oDRAM0_WE_N, // SDRAM0 Write Enable
58 output oDRAM1_WE_N, // SDRAM1 Write Enable
59 output oDRAM0_CAS_N, // SDRAM0 Column Address Strobe
60 output oDRAM1_CAS_N, // SDRAM1 Column Address Strobe
61 output oDRAM0_RAS_N, // SDRAM0 Row Address Strobe
62 output oDRAM1_RAS_N, // SDRAM1 Row Address Strobe
63 output oDRAM0_CS_N, // SDRAM0 Chip Select
64 output oDRAM1_CS_N, // SDRAM1 Chip Select
65 output [1:0] oDRAM0_BA, // SDRAM0 Bank Address
66 output [1:0] oDRAM1_BA, // SDRAM1 Bank Address
67 output oDRAM0_CLK, // SDRAM0 Clock
68 output oDRAM1_CLK, // SDRAM0 Clock
69 output oDRAM0_CKE, // SDRAM0 Clock Enable
70 output oDRAM1_CKE, // SDRAM1 Clock Enable
71 //////////////////////////////// Flash Interface ////////////////////////
72 inout [14:0] FLASH_DQ, // FLASH Data bus 15 Bits (0 to 14)
73 inout FLASH_DQ15_AM1, // FLASH Data bus Bit 15 or Address A-1
74 output [25:0] oFLASH_A, // FLASH Address bus 26 Bits
75 output oFLASH_WE_N, // FLASH Write Enable
76 output oFLASH_RST_N, // FLASH Reset
77 output oFLASH_WP_N, // FLASH Write Protect /Programming Acceleration
78 input iFLASH_RY_N, // FLASH Ready/Busy output
79 output oFLASH_BYTE_N, // FLASH Byte/Word Mode Configuration
80 output oFLASH_OE_N, // FLASH Output Enable
81 output oFLASH_CE_N, // FLASH Chip Enable
82 //////////////////////////////// SRAM Interface ////////////////////////
83 inout [31:0] SRAM_DQ, // SRAM Data Bus 32 Bits
84 inout [3:0] SRAM_DPA, // SRAM Parity Data Bus
85 output [20:0] oSRAM_A, // SRAM Address bus 21 Bits
86 output oSRAM_ADSC_N, // RAM Controller Address Status
87 output oSRAM_ADSP_N, // SRAM Processor Address Status
88 output oSRAM_ADV_N, // SRAM Burst Address Advance
89 output [3:0] oSRAM_BE_N, // SRAM Byte Write Enable
90 output oSRAM_CE1_N, // SRAM Chip Enable
91 output oSRAM_CE2, // SRAM Chip Enable
92 output oSRAM_CE3_N, // SRAM Chip Enable
93 output oSRAM_CLK, // SRAM Clock
94 output oSRAM_GW_N, // SRAM Global Write Enable
95 output oSRAM_OE_N, // SRAM Output Enable
96 output oSRAM_WE_N, // SRAM Write Enable
97 //////////////////////////////// ISP1362 Interface ////////////////////////
98 inout [15:0] OTG_D, // ISP1362 Data bus 16 Bits
99 output [1:0] oOTG_A, // ISP1362 Address 2 Bits
100 output oOTG_CS_N, // ISP1362 Chip Select
101 output oOTG_OE_N, // ISP1362 Read
102 output oOTG_WE_N, // ISP1362 Write
103 output oOTG_RESET_N, // ISP1362 Reset
104 inout OTG_FSPEED, // USB Full Speed, 0 = Enable, Z = Disable
105 inout OTG_LSPEED, // USB Low Speed, 0 = Enable, Z = Disable
106 input iOTG_INT0, // ISP1362 Interrupt 0
107 input iOTG_INT1, // ISP1362 Interrupt 1
108 input iOTG_DREQ0, // ISP1362 DMA Request 0
109 input iOTG_DREQ1, // ISP1362 DMA Request 1
110 output oOTG_DACK0_N, // ISP1362 DMA Acknowledge 0
111 output oOTG_DACK1_N, // ISP1362 DMA Acknowledge 1
112 //////////////////////////////// LCD Module 16X2 ////////////////////////////
113 inout [7:0] LCD_D, // LCD Data bus 8 bits
114 output oLCD_ON, // LCD Power ON/OFF
115 output oLCD_BLON, // LCD Back Light ON/OFF
116 output oLCD_RW, // LCD Read/Write Select, 0 = Write, 1 = Read
117 output oLCD_EN, // LCD Enable
118 output oLCD_RS, // LCD Command/Data Select, 0 = Command, 1 = Data
119 //////////////////////////////// SD Card Interface ////////////////////////
120 inout SD_DAT, // SD Card Data
121 inout SD_DAT3, // SD Card Data 3
122 inout SD_CMD, // SD Card Command Signal
123 output oSD_CLK, // SD Card Clock
124 //////////////////////////////// I2C ////////////////////////////////
125 inout I2C_SDAT, // I2C Data
126 output oI2C_SCLK, // I2C Clock
127 //////////////////////////////// PS2 ////////////////////////////
128 inout PS2_KBDAT, // PS2 Keyboard Data
129 inout PS2_KBCLK, // PS2 Keyboard Clock
130 inout PS2_MSDAT, // PS2 Mouse Data
131 inout PS2_MSCLK, // PS2 Mouse Clock
132 //////////////////////////////// VGA ////////////////////////////
133 output oVGA_CLOCK, // VGA Clock
134 output oVGA_HS, // VGA H_SYNC
135 output oVGA_VS, // VGA V_SYNC
136 output oVGA_BLANK_N, // VGA BLANK
137 output oVGA_SYNC_N, // VGA SYNC
138 output [9:0] oVGA_R, // VGA Red[9:0]
139 output [9:0] oVGA_G, // VGA Green[9:0]
140 output [9:0] oVGA_B, // VGA Blue[9:0]
141 //////////////////////////////// Ethernet Interface ////////////////////////////
142 inout [15:0] ENET_D, // DM9000A DATA bus 16Bits
143 output oENET_CMD, // DM9000A Command/Data Select, 0 = Command, 1 = Data
144 output oENET_CS_N, // DM9000A Chip Select
145 output oENET_IOW_N, // DM9000A Write
146 output oENET_IOR_N, // DM9000A Read
147 output oENET_RESET_N, // DM9000A Reset
148 input iENET_INT, // DM9000A Interrupt
149 output oENET_CLK, // DM9000A Clock 25 MHz
150 //////////////////////////////// Audio CODEC ////////////////////////////
151 inout AUD_ADCLRCK, // Audio CODEC ADC LR Clock
152 input iAUD_ADCDAT, // Audio CODEC ADC Data
153 inout AUD_DACLRCK, // Audio CODEC DAC LR Clock
154 output oAUD_DACDAT, // Audio CODEC DAC Data
155 inout AUD_BCLK, // Audio CODEC Bit-Stream Clock
156 output oAUD_XCK, // Audio CODEC Chip Clock
157 //////////////////////////////// TV Devoder ////////////////////////////
158 input iTD1_CLK27, // TV Decoder1 Line_Lock Output Clock
159 input [7:0] iTD1_D, // TV Decoder1 Data bus 8 bits
160 input iTD1_HS, // TV Decoder1 H_SYNC
161 input iTD1_VS, // TV Decoder1 V_SYNC
162 output oTD1_RESET_N, // TV Decoder1 Reset
163 input iTD2_CLK27, // TV Decoder2 Line_Lock Output Clock
164 input [7:0] iTD2_D, // TV Decoder2 Data bus 8 bits
165 input iTD2_HS, // TV Decoder2 H_SYNC
166 input iTD2_VS, // TV Decoder2 V_SYNC
167 output oTD2_RESET_N, // TV Decoder2 Reset
168 //////////////////////////////// GPIO ////////////////////////////////
169 inout [31:0] GPIO_0, // GPIO Connection 0 I/O
170 input GPIO_CLKIN_N0, // GPIO Connection 0 Clock Input 0
171 input GPIO_CLKIN_P0, // GPIO Connection 0 Clock Input 1
172 output GPIO_CLKOUT_N0, // GPIO Connection 0 Clock Output 0
173 output GPIO_CLKOUT_P0, // GPIO Connection 0 Clock Output 1
174 inout [31:0] GPIO_1, // GPIO Connection 1 I/O
175 input GPIO_CLKIN_N1, // GPIO Connection 1 Clock Input 0
176 input GPIO_CLKIN_P1, // GPIO Connection 1 Clock Input 1
177 output GPIO_CLKOUT_N1, // GPIO Connection 1 Clock Output 0
178 output GPIO_CLKOUT_P1 // PIO Connection 1 Clock Output 1
179 );
180
181 // All inout port turn to tri-state
182 assign SD_DAT = 1'bz;
183 assign GPIO_0 = 32'hzzzzzzzzz;
184 assign GPIO_1 = 32'hzzzzzzzzz;
185 assign AUD_ADCLRCK = 1'bz;
186
187 // Turn On TV Decoder
188 assign oTD1_RESET_N = 1'bz;
189 assign oTD2_RESET_N = 1'bz;
190
191 // Flash
192 assign FL_RST_N = 1'b1;
193
194 // 16*2 LCD Module
195 assign oLCD_ON = 1'b1; // LCD ON
196 assign oLCD_BLON = 1'b1; // LCD Back Light
197
198 // Disable USB speed select
199 assign OTG_FSPEED = 1'bz;
200 assign OTG_LSPEED = 1'bz;
201
202 // FLASH
203 wire FLASH_16BIT_IP_A0;
204 assign oFLASH_BYTE_N = 1'b1; // FLASH Byte/Word Mode Configuration
205 assign oFLASH_RST_N = 1'b1; // FLASH Reset
206 assign oFLASH_WP_N = 1'b1; // FLASH Write Protect /Programming Acceleration
207
208 // SSRAM
209 wire SRAM_CLK;
210 wire [1:0] SRAM_DUMMY_ADDR; // used to ignore the A0/A1 pin from Cypress SSRAM IP core
211
212 assign oSRAM_ADSP_N = 1'b1; // SRAM Processor Address Status
213 assign oSRAM_ADV_N = 1'b1; // SRAM Burst Address Advance
214 assign oSRAM_CE2 = ~oSRAM_CE1_N; // SRAM Chip Enable
215 assign oSRAM_CE3_N = oSRAM_CE1_N; // SRAM Chip Enable
216 assign oSRAM_GW_N = 1'b1; // SRAM Global Write Enable
217 assign oSRAM_CLK = SRAM_CLK;
218
219 // SDRAM
220 // the sdram is shahred with rtl and nios
221 wire [12:0] dram_a;
222 wire [1:0] dram_ba;
223 wire dram_cas_n;
224 wire dram_cke;
225 wire dram_cs_n;
226 wire [3:0] dram_dqm;
227 wire dram_ras_n;
228 wire dram_we_n;
229
230 // dram1
231 assign oDRAM0_CLK = SRAM_CLK; // SDRAM0 Clock
232 assign oDRAM1_CLK = SRAM_CLK; // SDRAM1 Clock
233
234 assign oDRAM0_A = dram_a;
235 assign oDRAM0_BA = dram_ba;
236 assign oDRAM0_CAS_N = dram_cas_n;
237 assign oDRAM0_CKE = dram_cke;
238 assign oDRAM0_CS_N = dram_cs_n;
239 assign oDRAM0_LDQM0 = dram_dqm[0];
240 assign oDRAM0_UDQM1 = dram_dqm[1];
241 assign oDRAM0_RAS_N = dram_ras_n;
242 assign oDRAM0_WE_N = dram_we_n;
243
244 // dram2
245 assign oDRAM1_A = dram_a;
246 assign oDRAM1_BA = dram_ba;
247 assign oDRAM1_CAS_N = dram_cas_n;
248 assign oDRAM1_CKE = dram_cke;
249 assign oDRAM1_CS_N = dram_cs_n;
250 assign oDRAM1_LDQM0 = dram_dqm[2];
251 assign oDRAM1_UDQM1 = dram_dqm[3];
252 assign oDRAM1_RAS_N = dram_ras_n;
253 assign oDRAM1_WE_N = dram_we_n;
254
255 // USB
256 assign OTG_FSPEED = 1'bz; // USB Full Speed, 0 = Enable, Z = Disable
257 assign OTG_LSPEED = 1'bz; // USB Low Speed, 0 = Enable, Z = Disable
258
259 // Clock 25MHz
260 reg iCLK_25;
261
262 always@(posedge iCLK_50)
263 iCLK_25 <= ~iCLK_25;
264
265 // NIOS CPU
266 wire CPU_CLK;
267 wire CPU_RESET_N;
268
269 Reset_Delay delay0 (
270 .iRST(iKEY[0]),
271 .iCLK(iCLK_50),
272 .oRESET(CPU_RESET_N)
273 );
274
275 // NIOS II system
276 nios_ii nios_ii0 (
277 // 1) global signals:
278 .clk_50(iCLK_50),
279 .pll_c0_system(CPU_CLK),
280 .pll_c1_memory(SRAM_CLK),
281 .pll_c2_audio(oAUD_XCK),
282 .reset_n(CPU_RESET_N),
283 .clk_25(iCLK_25),
284 // the_DM9000A_IF_0
285 .avs_s1_export_ENET_CLK_from_the_DM9000A(oENET_CLK),
286 .avs_s1_export_ENET_CMD_from_the_DM9000A(oENET_CMD),
287 .avs_s1_export_ENET_CS_N_from_the_DM9000A(oENET_CS_N),
288 .avs_s1_export_ENET_DATA_to_and_from_the_DM9000A(ENET_D),
289 .avs_s1_export_ENET_INT_to_the_DM9000A(iENET_INT),
290 .avs_s1_export_ENET_RD_N_from_the_DM9000A(oENET_IOR_N),
291 .avs_s1_export_ENET_RST_N_from_the_DM9000A(oENET_RESET_N),
292 .avs_s1_export_ENET_WR_N_from_the_DM9000A(oENET_IOW_N),
293 // the_ISP1362
294 .avs_hc_export_OTG_ADDR_from_the_ISP1362(oOTG_A),
295 .avs_hc_export_OTG_CS_N_from_the_ISP1362(oOTG_CS_N),
296 .avs_hc_export_OTG_DATA_to_and_from_the_ISP1362(OTG_D),
297 .avs_hc_export_OTG_INT0_to_the_ISP1362(iOTG_INT0),
298 .avs_hc_export_OTG_RD_N_from_the_ISP1362(oOTG_OE_N),
299 .avs_hc_export_OTG_RST_N_from_the_ISP1362(oOTG_RESET_N),
300 .avs_hc_export_OTG_WR_N_from_the_ISP1362(oOTG_WE_N),
301 .avs_dc_export_OTG_INT1_to_the_ISP1362(iOTG_INT1),
302 // the_audio
303 .avs_s1_export_BCLK_to_the_AUDIO(AUD_BCLK),
304 .avs_s1_export_DACLRC_to_the_AUDIO(AUD_DACLRCK),
305 .avs_s1_export_DACDAT_from_the_AUDIO(oAUD_DACDAT),
306 .avs_s1_export_ADCLRC_to_the_AUDIO(AUD_ADCLRCK),
307 .avs_s1_export_ADCDAT_to_the_AUDIO(iAUD_ADCDAT),
308 // the_i2c_sclk
309 .out_port_from_the_i2c_sclk(oI2C_SCLK),
310 // the_i2c_sdat
311 .bidir_port_to_and_from_the_i2c_sdat(I2C_SDAT),
312 // the_lcd
313 .LCD_E_from_the_lcd(oLCD_EN),
314 .LCD_RS_from_the_lcd(oLCD_RS),
315 .LCD_RW_from_the_lcd(oLCD_RW),
316 .LCD_data_to_and_from_the_lcd(LCD_D),
317 // the_pio_button
318 .in_port_to_the_pio_button(iKEY),
319 // the_pio_green_led
320 .out_port_from_the_pio_green_led(oLEDG),
321 // the_pio_red_led
322 .out_port_from_the_pio_red_led(oLEDR),
323 // the_seg7
324 .avs_s1_export_seg7_from_the_SEG7({oHEX7_DP, oHEX7_D, oHEX6_DP, oHEX6_D, oHEX5_DP,
325 oHEX5_D, oHEX4_DP,oHEX4_D, oHEX3_DP, oHEX3_D, oHEX2_DP, oHEX2_D, oHEX1_DP, oHEX1_D,
326 oHEX0_DP, oHEX0_D}),
327 // the_pio_switch
328 .in_port_to_the_pio_switch(iSW),
329 // the_sd_clk
330 .out_port_from_the_sd_clk(oSD_CLK),
331 // the_sd_cmd
332 .bidir_port_to_and_from_the_sd_cmd(SD_CMD),
333 // the_sd_dat
334 .bidir_port_to_and_from_the_sd_dat(SD_DAT),
335 // the_sd_dat3
336 .bidir_port_to_and_from_the_sd_dat3(SD_DAT3),
337 // the_sdram (u1)
338 .zs_addr_from_the_sdram_u1(dram_a),
339 .zs_ba_from_the_sdram_u1(dram_ba),
340 .zs_cas_n_from_the_sdram_u1(dram_cas_n),
341 .zs_cke_from_the_sdram_u1(dram_cke),
342 .zs_cs_n_from_the_sdram_u1(dram_cs_n),
343 .zs_dq_to_and_from_the_sdram_u1(DRAM_DQ),
344 .zs_dqm_from_the_sdram_u1(dram_dqm),
345 .zs_ras_n_from_the_sdram_u1(dram_ras_n),
346 .zs_we_n_from_the_sdram_u1(dram_we_n),
347 // the_tristate_bridge_avalon_slave (flash)
348 .address_to_the_cfi_flash({oFLASH_A[21:0],FLASH_16BIT_IP_A0}),
349 .data_to_and_from_the_cfi_flash({FLASH_DQ15_AM1,FLASH_DQ}),
350 .read_n_to_the_cfi_flash(oFLASH_OE_N),
351 .select_n_to_the_cfi_flash(oFLASH_CE_N),
352 .write_n_to_the_cfi_flash(oFLASH_WE_N),
353 // the_tristate_bridge_1_avalon_slave (ssram)
354 .address_to_the_ssram({oSRAM_A[17:0],SRAM_DUMMY_ADDR}),
355 .adsc_n_to_the_ssram(oSRAM_ADSC_N),
356 .bw_n_to_the_ssram(oSRAM_BE_N),
357 .bwe_n_to_the_ssram(oSRAM_WE_N),
358 .chipenable1_n_to_the_ssram(oSRAM_CE1_N),
359 .data_to_and_from_the_ssram((SRAM_DQ)),
360 .outputenable_n_to_the_ssram(oSRAM_OE_N),
361 // the_uart
362 .cts_n_to_the_uart(oUART_CTS),
363 .rts_n_from_the_uart(iUART_RTS),
364 .rxd_to_the_uart(iUART_RXD),
365 .txd_from_the_uart(oUART_TXD),
366 );
367
368 endmodule
2 (C) OOMusou 2008 http://oomusou.cnblogs.com
3
4 Filename : DE2_70_NIOS.v
5 Compiler : Quartus II 8.1
6 Description : DE2_70_NIOS reference design 1.1
7 Release : 11/25/2008 1.0
8 */
9
10 module DE2_70_NIOS (
11 input iCLK_28, // 28.63636 MHz
12 input iCLK_50, // 50 MHz
13 input iCLK_50_2, // 50 MHz
14 input iCLK_50_3, // 50 MHz
15 input iCLK_50_4, // 50 MHz
16 input iEXT_CLOCK, // External Clock
17 ////////////////////////////// Push Button ////////////////////////
18 input [3:0] iKEY, // Pushbutton[3:0]
19 ////////////////////////////// DPDT Switch ////////////////////////
20 input [17:0] iSW, // Toggle Switch[17:0]
21 ////////////////////////////// 7-SEG Dispaly ////////////////////////
22 output [6:0] oHEX0_D, // Seven Segment Digit 0
23 output oHEX0_DP, // Seven Segment Digit 0 decimal point
24 output [6:0] oHEX1_D, // Seven Segment Digit 1
25 output oHEX1_DP, // Seven Segment Digit 1 decimal point
26 output [6:0] oHEX2_D, // Seven Segment Digit 2
27 output oHEX2_DP, // Seven Segment Digit 2 decimal point
28 output [6:0] oHEX3_D, // Seven Segment Digit 3
29 output oHEX3_DP, // Seven Segment Digit 3 decimal point
30 output [6:0] oHEX4_D, // Seven Segment Digit 4
31 output oHEX4_DP, // Seven Segment Digit 4 decimal point
32 output [6:0] oHEX5_D, // Seven Segment Digit 5
33 output oHEX5_DP, // Seven Segment Digit 5 decimal point
34 output [6:0] oHEX6_D, // Seven Segment Digit 6
35 output oHEX6_DP, // Seven Segment Digit 6 decimal point
36 output [6:0] oHEX7_D, // Seven Segment Digit 7
37 output oHEX7_DP, // Seven Segment Digit 7 decimal point
38 //////////////////////////////// LED ////////////////////////////
39 output [8:0] oLEDG, // LED Green[8:0]
40 output [17:0] oLEDR, // LED Red[17:0]
41 //////////////////////////////// UART ////////////////////////////
42 output oUART_TXD, // UART Transmitter
43 input iUART_RXD, // UART Receiver
44 output oUART_CTS, // UART Clear To Send
45 input iUART_RTS, // UART Requst To Send
46 //////////////////////////////// IRDA ////////////////////////////
47 output oIRDA_TXD, // IRDA Transmitter
48 input iIRDA_RXD, // IRDA Receiver
49 //////////////////////////////// SDRAM Interface ////////////////////////
50 inout [31:0] DRAM_DQ, // SDRAM Data bus 32 Bits
51 output [12:0] oDRAM0_A, // SDRAM0 Address bus 12 Bits
52 output [12:0] oDRAM1_A, // SDRAM1 Address bus 12 Bits
53 output oDRAM0_LDQM0, // SDRAM0 Low-byte Data Mask
54 output oDRAM1_LDQM0, // SDRAM1 Low-byte Data Mask
55 output oDRAM0_UDQM1, // SDRAM0 High-byte Data Mask
56 output oDRAM1_UDQM1, // SDRAM1 High-byte Data Mask
57 output oDRAM0_WE_N, // SDRAM0 Write Enable
58 output oDRAM1_WE_N, // SDRAM1 Write Enable
59 output oDRAM0_CAS_N, // SDRAM0 Column Address Strobe
60 output oDRAM1_CAS_N, // SDRAM1 Column Address Strobe
61 output oDRAM0_RAS_N, // SDRAM0 Row Address Strobe
62 output oDRAM1_RAS_N, // SDRAM1 Row Address Strobe
63 output oDRAM0_CS_N, // SDRAM0 Chip Select
64 output oDRAM1_CS_N, // SDRAM1 Chip Select
65 output [1:0] oDRAM0_BA, // SDRAM0 Bank Address
66 output [1:0] oDRAM1_BA, // SDRAM1 Bank Address
67 output oDRAM0_CLK, // SDRAM0 Clock
68 output oDRAM1_CLK, // SDRAM0 Clock
69 output oDRAM0_CKE, // SDRAM0 Clock Enable
70 output oDRAM1_CKE, // SDRAM1 Clock Enable
71 //////////////////////////////// Flash Interface ////////////////////////
72 inout [14:0] FLASH_DQ, // FLASH Data bus 15 Bits (0 to 14)
73 inout FLASH_DQ15_AM1, // FLASH Data bus Bit 15 or Address A-1
74 output [25:0] oFLASH_A, // FLASH Address bus 26 Bits
75 output oFLASH_WE_N, // FLASH Write Enable
76 output oFLASH_RST_N, // FLASH Reset
77 output oFLASH_WP_N, // FLASH Write Protect /Programming Acceleration
78 input iFLASH_RY_N, // FLASH Ready/Busy output
79 output oFLASH_BYTE_N, // FLASH Byte/Word Mode Configuration
80 output oFLASH_OE_N, // FLASH Output Enable
81 output oFLASH_CE_N, // FLASH Chip Enable
82 //////////////////////////////// SRAM Interface ////////////////////////
83 inout [31:0] SRAM_DQ, // SRAM Data Bus 32 Bits
84 inout [3:0] SRAM_DPA, // SRAM Parity Data Bus
85 output [20:0] oSRAM_A, // SRAM Address bus 21 Bits
86 output oSRAM_ADSC_N, // RAM Controller Address Status
87 output oSRAM_ADSP_N, // SRAM Processor Address Status
88 output oSRAM_ADV_N, // SRAM Burst Address Advance
89 output [3:0] oSRAM_BE_N, // SRAM Byte Write Enable
90 output oSRAM_CE1_N, // SRAM Chip Enable
91 output oSRAM_CE2, // SRAM Chip Enable
92 output oSRAM_CE3_N, // SRAM Chip Enable
93 output oSRAM_CLK, // SRAM Clock
94 output oSRAM_GW_N, // SRAM Global Write Enable
95 output oSRAM_OE_N, // SRAM Output Enable
96 output oSRAM_WE_N, // SRAM Write Enable
97 //////////////////////////////// ISP1362 Interface ////////////////////////
98 inout [15:0] OTG_D, // ISP1362 Data bus 16 Bits
99 output [1:0] oOTG_A, // ISP1362 Address 2 Bits
100 output oOTG_CS_N, // ISP1362 Chip Select
101 output oOTG_OE_N, // ISP1362 Read
102 output oOTG_WE_N, // ISP1362 Write
103 output oOTG_RESET_N, // ISP1362 Reset
104 inout OTG_FSPEED, // USB Full Speed, 0 = Enable, Z = Disable
105 inout OTG_LSPEED, // USB Low Speed, 0 = Enable, Z = Disable
106 input iOTG_INT0, // ISP1362 Interrupt 0
107 input iOTG_INT1, // ISP1362 Interrupt 1
108 input iOTG_DREQ0, // ISP1362 DMA Request 0
109 input iOTG_DREQ1, // ISP1362 DMA Request 1
110 output oOTG_DACK0_N, // ISP1362 DMA Acknowledge 0
111 output oOTG_DACK1_N, // ISP1362 DMA Acknowledge 1
112 //////////////////////////////// LCD Module 16X2 ////////////////////////////
113 inout [7:0] LCD_D, // LCD Data bus 8 bits
114 output oLCD_ON, // LCD Power ON/OFF
115 output oLCD_BLON, // LCD Back Light ON/OFF
116 output oLCD_RW, // LCD Read/Write Select, 0 = Write, 1 = Read
117 output oLCD_EN, // LCD Enable
118 output oLCD_RS, // LCD Command/Data Select, 0 = Command, 1 = Data
119 //////////////////////////////// SD Card Interface ////////////////////////
120 inout SD_DAT, // SD Card Data
121 inout SD_DAT3, // SD Card Data 3
122 inout SD_CMD, // SD Card Command Signal
123 output oSD_CLK, // SD Card Clock
124 //////////////////////////////// I2C ////////////////////////////////
125 inout I2C_SDAT, // I2C Data
126 output oI2C_SCLK, // I2C Clock
127 //////////////////////////////// PS2 ////////////////////////////
128 inout PS2_KBDAT, // PS2 Keyboard Data
129 inout PS2_KBCLK, // PS2 Keyboard Clock
130 inout PS2_MSDAT, // PS2 Mouse Data
131 inout PS2_MSCLK, // PS2 Mouse Clock
132 //////////////////////////////// VGA ////////////////////////////
133 output oVGA_CLOCK, // VGA Clock
134 output oVGA_HS, // VGA H_SYNC
135 output oVGA_VS, // VGA V_SYNC
136 output oVGA_BLANK_N, // VGA BLANK
137 output oVGA_SYNC_N, // VGA SYNC
138 output [9:0] oVGA_R, // VGA Red[9:0]
139 output [9:0] oVGA_G, // VGA Green[9:0]
140 output [9:0] oVGA_B, // VGA Blue[9:0]
141 //////////////////////////////// Ethernet Interface ////////////////////////////
142 inout [15:0] ENET_D, // DM9000A DATA bus 16Bits
143 output oENET_CMD, // DM9000A Command/Data Select, 0 = Command, 1 = Data
144 output oENET_CS_N, // DM9000A Chip Select
145 output oENET_IOW_N, // DM9000A Write
146 output oENET_IOR_N, // DM9000A Read
147 output oENET_RESET_N, // DM9000A Reset
148 input iENET_INT, // DM9000A Interrupt
149 output oENET_CLK, // DM9000A Clock 25 MHz
150 //////////////////////////////// Audio CODEC ////////////////////////////
151 inout AUD_ADCLRCK, // Audio CODEC ADC LR Clock
152 input iAUD_ADCDAT, // Audio CODEC ADC Data
153 inout AUD_DACLRCK, // Audio CODEC DAC LR Clock
154 output oAUD_DACDAT, // Audio CODEC DAC Data
155 inout AUD_BCLK, // Audio CODEC Bit-Stream Clock
156 output oAUD_XCK, // Audio CODEC Chip Clock
157 //////////////////////////////// TV Devoder ////////////////////////////
158 input iTD1_CLK27, // TV Decoder1 Line_Lock Output Clock
159 input [7:0] iTD1_D, // TV Decoder1 Data bus 8 bits
160 input iTD1_HS, // TV Decoder1 H_SYNC
161 input iTD1_VS, // TV Decoder1 V_SYNC
162 output oTD1_RESET_N, // TV Decoder1 Reset
163 input iTD2_CLK27, // TV Decoder2 Line_Lock Output Clock
164 input [7:0] iTD2_D, // TV Decoder2 Data bus 8 bits
165 input iTD2_HS, // TV Decoder2 H_SYNC
166 input iTD2_VS, // TV Decoder2 V_SYNC
167 output oTD2_RESET_N, // TV Decoder2 Reset
168 //////////////////////////////// GPIO ////////////////////////////////
169 inout [31:0] GPIO_0, // GPIO Connection 0 I/O
170 input GPIO_CLKIN_N0, // GPIO Connection 0 Clock Input 0
171 input GPIO_CLKIN_P0, // GPIO Connection 0 Clock Input 1
172 output GPIO_CLKOUT_N0, // GPIO Connection 0 Clock Output 0
173 output GPIO_CLKOUT_P0, // GPIO Connection 0 Clock Output 1
174 inout [31:0] GPIO_1, // GPIO Connection 1 I/O
175 input GPIO_CLKIN_N1, // GPIO Connection 1 Clock Input 0
176 input GPIO_CLKIN_P1, // GPIO Connection 1 Clock Input 1
177 output GPIO_CLKOUT_N1, // GPIO Connection 1 Clock Output 0
178 output GPIO_CLKOUT_P1 // PIO Connection 1 Clock Output 1
179 );
180
181 // All inout port turn to tri-state
182 assign SD_DAT = 1'bz;
183 assign GPIO_0 = 32'hzzzzzzzzz;
184 assign GPIO_1 = 32'hzzzzzzzzz;
185 assign AUD_ADCLRCK = 1'bz;
186
187 // Turn On TV Decoder
188 assign oTD1_RESET_N = 1'bz;
189 assign oTD2_RESET_N = 1'bz;
190
191 // Flash
192 assign FL_RST_N = 1'b1;
193
194 // 16*2 LCD Module
195 assign oLCD_ON = 1'b1; // LCD ON
196 assign oLCD_BLON = 1'b1; // LCD Back Light
197
198 // Disable USB speed select
199 assign OTG_FSPEED = 1'bz;
200 assign OTG_LSPEED = 1'bz;
201
202 // FLASH
203 wire FLASH_16BIT_IP_A0;
204 assign oFLASH_BYTE_N = 1'b1; // FLASH Byte/Word Mode Configuration
205 assign oFLASH_RST_N = 1'b1; // FLASH Reset
206 assign oFLASH_WP_N = 1'b1; // FLASH Write Protect /Programming Acceleration
207
208 // SSRAM
209 wire SRAM_CLK;
210 wire [1:0] SRAM_DUMMY_ADDR; // used to ignore the A0/A1 pin from Cypress SSRAM IP core
211
212 assign oSRAM_ADSP_N = 1'b1; // SRAM Processor Address Status
213 assign oSRAM_ADV_N = 1'b1; // SRAM Burst Address Advance
214 assign oSRAM_CE2 = ~oSRAM_CE1_N; // SRAM Chip Enable
215 assign oSRAM_CE3_N = oSRAM_CE1_N; // SRAM Chip Enable
216 assign oSRAM_GW_N = 1'b1; // SRAM Global Write Enable
217 assign oSRAM_CLK = SRAM_CLK;
218
219 // SDRAM
220 // the sdram is shahred with rtl and nios
221 wire [12:0] dram_a;
222 wire [1:0] dram_ba;
223 wire dram_cas_n;
224 wire dram_cke;
225 wire dram_cs_n;
226 wire [3:0] dram_dqm;
227 wire dram_ras_n;
228 wire dram_we_n;
229
230 // dram1
231 assign oDRAM0_CLK = SRAM_CLK; // SDRAM0 Clock
232 assign oDRAM1_CLK = SRAM_CLK; // SDRAM1 Clock
233
234 assign oDRAM0_A = dram_a;
235 assign oDRAM0_BA = dram_ba;
236 assign oDRAM0_CAS_N = dram_cas_n;
237 assign oDRAM0_CKE = dram_cke;
238 assign oDRAM0_CS_N = dram_cs_n;
239 assign oDRAM0_LDQM0 = dram_dqm[0];
240 assign oDRAM0_UDQM1 = dram_dqm[1];
241 assign oDRAM0_RAS_N = dram_ras_n;
242 assign oDRAM0_WE_N = dram_we_n;
243
244 // dram2
245 assign oDRAM1_A = dram_a;
246 assign oDRAM1_BA = dram_ba;
247 assign oDRAM1_CAS_N = dram_cas_n;
248 assign oDRAM1_CKE = dram_cke;
249 assign oDRAM1_CS_N = dram_cs_n;
250 assign oDRAM1_LDQM0 = dram_dqm[2];
251 assign oDRAM1_UDQM1 = dram_dqm[3];
252 assign oDRAM1_RAS_N = dram_ras_n;
253 assign oDRAM1_WE_N = dram_we_n;
254
255 // USB
256 assign OTG_FSPEED = 1'bz; // USB Full Speed, 0 = Enable, Z = Disable
257 assign OTG_LSPEED = 1'bz; // USB Low Speed, 0 = Enable, Z = Disable
258
259 // Clock 25MHz
260 reg iCLK_25;
261
262 always@(posedge iCLK_50)
263 iCLK_25 <= ~iCLK_25;
264
265 // NIOS CPU
266 wire CPU_CLK;
267 wire CPU_RESET_N;
268
269 Reset_Delay delay0 (
270 .iRST(iKEY[0]),
271 .iCLK(iCLK_50),
272 .oRESET(CPU_RESET_N)
273 );
274
275 // NIOS II system
276 nios_ii nios_ii0 (
277 // 1) global signals:
278 .clk_50(iCLK_50),
279 .pll_c0_system(CPU_CLK),
280 .pll_c1_memory(SRAM_CLK),
281 .pll_c2_audio(oAUD_XCK),
282 .reset_n(CPU_RESET_N),
283 .clk_25(iCLK_25),
284 // the_DM9000A_IF_0
285 .avs_s1_export_ENET_CLK_from_the_DM9000A(oENET_CLK),
286 .avs_s1_export_ENET_CMD_from_the_DM9000A(oENET_CMD),
287 .avs_s1_export_ENET_CS_N_from_the_DM9000A(oENET_CS_N),
288 .avs_s1_export_ENET_DATA_to_and_from_the_DM9000A(ENET_D),
289 .avs_s1_export_ENET_INT_to_the_DM9000A(iENET_INT),
290 .avs_s1_export_ENET_RD_N_from_the_DM9000A(oENET_IOR_N),
291 .avs_s1_export_ENET_RST_N_from_the_DM9000A(oENET_RESET_N),
292 .avs_s1_export_ENET_WR_N_from_the_DM9000A(oENET_IOW_N),
293 // the_ISP1362
294 .avs_hc_export_OTG_ADDR_from_the_ISP1362(oOTG_A),
295 .avs_hc_export_OTG_CS_N_from_the_ISP1362(oOTG_CS_N),
296 .avs_hc_export_OTG_DATA_to_and_from_the_ISP1362(OTG_D),
297 .avs_hc_export_OTG_INT0_to_the_ISP1362(iOTG_INT0),
298 .avs_hc_export_OTG_RD_N_from_the_ISP1362(oOTG_OE_N),
299 .avs_hc_export_OTG_RST_N_from_the_ISP1362(oOTG_RESET_N),
300 .avs_hc_export_OTG_WR_N_from_the_ISP1362(oOTG_WE_N),
301 .avs_dc_export_OTG_INT1_to_the_ISP1362(iOTG_INT1),
302 // the_audio
303 .avs_s1_export_BCLK_to_the_AUDIO(AUD_BCLK),
304 .avs_s1_export_DACLRC_to_the_AUDIO(AUD_DACLRCK),
305 .avs_s1_export_DACDAT_from_the_AUDIO(oAUD_DACDAT),
306 .avs_s1_export_ADCLRC_to_the_AUDIO(AUD_ADCLRCK),
307 .avs_s1_export_ADCDAT_to_the_AUDIO(iAUD_ADCDAT),
308 // the_i2c_sclk
309 .out_port_from_the_i2c_sclk(oI2C_SCLK),
310 // the_i2c_sdat
311 .bidir_port_to_and_from_the_i2c_sdat(I2C_SDAT),
312 // the_lcd
313 .LCD_E_from_the_lcd(oLCD_EN),
314 .LCD_RS_from_the_lcd(oLCD_RS),
315 .LCD_RW_from_the_lcd(oLCD_RW),
316 .LCD_data_to_and_from_the_lcd(LCD_D),
317 // the_pio_button
318 .in_port_to_the_pio_button(iKEY),
319 // the_pio_green_led
320 .out_port_from_the_pio_green_led(oLEDG),
321 // the_pio_red_led
322 .out_port_from_the_pio_red_led(oLEDR),
323 // the_seg7
324 .avs_s1_export_seg7_from_the_SEG7({oHEX7_DP, oHEX7_D, oHEX6_DP, oHEX6_D, oHEX5_DP,
325 oHEX5_D, oHEX4_DP,oHEX4_D, oHEX3_DP, oHEX3_D, oHEX2_DP, oHEX2_D, oHEX1_DP, oHEX1_D,
326 oHEX0_DP, oHEX0_D}),
327 // the_pio_switch
328 .in_port_to_the_pio_switch(iSW),
329 // the_sd_clk
330 .out_port_from_the_sd_clk(oSD_CLK),
331 // the_sd_cmd
332 .bidir_port_to_and_from_the_sd_cmd(SD_CMD),
333 // the_sd_dat
334 .bidir_port_to_and_from_the_sd_dat(SD_DAT),
335 // the_sd_dat3
336 .bidir_port_to_and_from_the_sd_dat3(SD_DAT3),
337 // the_sdram (u1)
338 .zs_addr_from_the_sdram_u1(dram_a),
339 .zs_ba_from_the_sdram_u1(dram_ba),
340 .zs_cas_n_from_the_sdram_u1(dram_cas_n),
341 .zs_cke_from_the_sdram_u1(dram_cke),
342 .zs_cs_n_from_the_sdram_u1(dram_cs_n),
343 .zs_dq_to_and_from_the_sdram_u1(DRAM_DQ),
344 .zs_dqm_from_the_sdram_u1(dram_dqm),
345 .zs_ras_n_from_the_sdram_u1(dram_ras_n),
346 .zs_we_n_from_the_sdram_u1(dram_we_n),
347 // the_tristate_bridge_avalon_slave (flash)
348 .address_to_the_cfi_flash({oFLASH_A[21:0],FLASH_16BIT_IP_A0}),
349 .data_to_and_from_the_cfi_flash({FLASH_DQ15_AM1,FLASH_DQ}),
350 .read_n_to_the_cfi_flash(oFLASH_OE_N),
351 .select_n_to_the_cfi_flash(oFLASH_CE_N),
352 .write_n_to_the_cfi_flash(oFLASH_WE_N),
353 // the_tristate_bridge_1_avalon_slave (ssram)
354 .address_to_the_ssram({oSRAM_A[17:0],SRAM_DUMMY_ADDR}),
355 .adsc_n_to_the_ssram(oSRAM_ADSC_N),
356 .bw_n_to_the_ssram(oSRAM_BE_N),
357 .bwe_n_to_the_ssram(oSRAM_WE_N),
358 .chipenable1_n_to_the_ssram(oSRAM_CE1_N),
359 .data_to_and_from_the_ssram((SRAM_DQ)),
360 .outputenable_n_to_the_ssram(oSRAM_OE_N),
361 // the_uart
362 .cts_n_to_the_uart(oUART_CTS),
363 .rts_n_from_the_uart(iUART_RTS),
364 .rxd_to_the_uart(iUART_RXD),
365 .txd_from_the_uart(oUART_TXD),
366 );
367
368 endmodule
219行
// SDRAM
// the sdram is shahred with rtl and nios
wire [12:0] dram_a;
wire [1:0] dram_ba;
wire dram_cas_n;
wire dram_cke;
wire dram_cs_n;
wire [3:0] dram_dqm;
wire dram_ras_n;
wire dram_we_n;
// dram1
assign oDRAM0_CLK = SRAM_CLK; // SDRAM0 Clock
assign oDRAM1_CLK = SRAM_CLK; // SDRAM1 Clock
assign oDRAM0_A = dram_a;
assign oDRAM0_BA = dram_ba;
assign oDRAM0_CAS_N = dram_cas_n;
assign oDRAM0_CKE = dram_cke;
assign oDRAM0_CS_N = dram_cs_n;
assign oDRAM0_LDQM0 = dram_dqm[0];
assign oDRAM0_UDQM1 = dram_dqm[1];
assign oDRAM0_RAS_N = dram_ras_n;
assign oDRAM0_WE_N = dram_we_n;
// dram2
assign oDRAM1_A = dram_a;
assign oDRAM1_BA = dram_ba;
assign oDRAM1_CAS_N = dram_cas_n;
assign oDRAM1_CKE = dram_cke;
assign oDRAM1_CS_N = dram_cs_n;
assign oDRAM1_LDQM0 = dram_dqm[2];
assign oDRAM1_UDQM1 = dram_dqm[3];
assign oDRAM1_RAS_N = dram_ras_n;
assign oDRAM1_WE_N = dram_we_n;
// the sdram is shahred with rtl and nios
wire [12:0] dram_a;
wire [1:0] dram_ba;
wire dram_cas_n;
wire dram_cke;
wire dram_cs_n;
wire [3:0] dram_dqm;
wire dram_ras_n;
wire dram_we_n;
// dram1
assign oDRAM0_CLK = SRAM_CLK; // SDRAM0 Clock
assign oDRAM1_CLK = SRAM_CLK; // SDRAM1 Clock
assign oDRAM0_A = dram_a;
assign oDRAM0_BA = dram_ba;
assign oDRAM0_CAS_N = dram_cas_n;
assign oDRAM0_CKE = dram_cke;
assign oDRAM0_CS_N = dram_cs_n;
assign oDRAM0_LDQM0 = dram_dqm[0];
assign oDRAM0_UDQM1 = dram_dqm[1];
assign oDRAM0_RAS_N = dram_ras_n;
assign oDRAM0_WE_N = dram_we_n;
// dram2
assign oDRAM1_A = dram_a;
assign oDRAM1_BA = dram_ba;
assign oDRAM1_CAS_N = dram_cas_n;
assign oDRAM1_CKE = dram_cke;
assign oDRAM1_CS_N = dram_cs_n;
assign oDRAM1_LDQM0 = dram_dqm[2];
assign oDRAM1_UDQM1 = dram_dqm[3];
assign oDRAM1_RAS_N = dram_ras_n;
assign oDRAM1_WE_N = dram_we_n;
宣告從SOPC的SDRAM port所連出的wire，並且連到top module的SDRAM port。
關鍵在於DRAM_DQ是個inout [31:0]，不能設成wire，必須要直接從SOPC接出來，我第一次就是這樣失敗的。
337行
// the_sdram (u1)
.zs_addr_from_the_sdram_u1(dram_a),
.zs_ba_from_the_sdram_u1(dram_ba),
.zs_cas_n_from_the_sdram_u1(dram_cas_n),
.zs_cke_from_the_sdram_u1(dram_cke),
.zs_cs_n_from_the_sdram_u1(dram_cs_n),
.zs_dq_to_and_from_the_sdram_u1(DRAM_DQ),
.zs_dqm_from_the_sdram_u1(dram_dqm),
.zs_ras_n_from_the_sdram_u1(dram_ras_n),
.zs_we_n_from_the_sdram_u1(dram_we_n),
.zs_addr_from_the_sdram_u1(dram_a),
.zs_ba_from_the_sdram_u1(dram_ba),
.zs_cas_n_from_the_sdram_u1(dram_cas_n),
.zs_cke_from_the_sdram_u1(dram_cke),
.zs_cs_n_from_the_sdram_u1(dram_cs_n),
.zs_dq_to_and_from_the_sdram_u1(DRAM_DQ),
.zs_dqm_from_the_sdram_u1(dram_dqm),
.zs_ras_n_from_the_sdram_u1(dram_ras_n),
.zs_we_n_from_the_sdram_u1(dram_we_n),
從SOPC的SDRAM port連出的wire。
證明這種方式的正確性
從三個方式來證明：
1.執行Hello World project template，並將Nios II程式跑在SDRAM上。
2.執行Hello MicroC/OS-II project template，並將Nios II程式跑在SDRAM上。
3.執行Memory Test project template，證明64MB SDRAM皆可正常存取。
1.Hello World
執行結果
2.Hello MicroC/OS-II
執行結果
3.Memory Test
儘管能順利的在SDRAM執行Hello World與Hello MicroC/OS-II，還是很令人擔心這種方式是否能正確的存取DE2-70的64MB SDRAM，為了客觀起見，我們使用了Nios II內建的Memory Test project template。
Step 1：
使用Memory Test project template
Step 2：
將Nios II跑在SSRAM
因為SDRAM即將接受測試，所以將Nios II程式跑在SSRAM上
Step 3：
執行Memory Test
因為要測試SDRAM，所以輸入a繼續。
接著要我們輸入要測試的memory起始位置與結束位置，該怎麼填呢?回想一下SOPC Builder怎麼對SDRAM定址。
根據SOPC Builder，0x04000000為SDRAM的起始位置，0x07ffffff為結束位置。
執行結果
證明64MB SDRAM通過測試。
完整程式碼下載
DE2_70_NIOS_11.7z
Conclusion
或許有些人喜歡將2顆SDRAM分開使用，甚至有人1顆SDRAM是掛在Avalon bus上，另外1顆直接使用Sdram_Control_4Port控制；這就類似有人喜歡一顆硬碟分割成好幾個磁區，也有人喜歡將好幾顆硬碟合併成一顆使用。不過以傳輸來說，既然Nios II CPU是32 bit，所有的ip都是32 bit，SDRAM的16 bit反而是傳輸上的瓶頸，透過本文雙通道的方式，將2顆16 bit SDRAM合併成1顆32 bit SDRAM使用，可以讓整個系統順暢的以32 bit運行，不再需要Avalon bus的Dynamic Bus Sizing機制，充分發揮DE2-70兩顆SDRAM的優勢。
See Also
(原創) 哪裡有DE2-70的Nios II reference design可以參考? (SOC) (DE2-70) (Nios II) (SOPC Builder)
(原創) avm_m1_writedata[15:0] 與 avm_m1_writedata[31:0]配合avm_m1_byteenable = 4'b0011意義是否一樣? (SOC) (SOPC Builder) (DE2-70)
(原創) 如何使用Pipeline Bridge增進Nios II系統的Fmax? (SOC) (Quartus II) (Nios II) (SOPC Builder) (DE2-70)
