本帖最后由 pq113_6 于 2022-6-19 11:48 编辑
板子是GD32450I_EVAL_Demo，SDRAM初始化已经OK。测试代码：- uint8_t *pbAddr = (uint8_t *)EXMC_SDRAM_ADDR0;
- uint16_t i;
- uint16_t max = 4;
- uint8_t *pbTemp;
- Printf("SDRAM Test Start:%x\n", sdramPage * 1024);
- for (i = 0; i < max; i++)
- {
- pbTemp = (uint8_t *)(pbAddr + (uint32_t)sdramPage * 1024 + i);
- *(uint8_t *)pbTemp = (i & 0xff);
- }
- for (i = 0; i < max; i++)
- {
- pbTemp = (uint8_t *)(pbAddr + (uint32_t)sdramPage * 1024 + i);
- if(*pbTemp != (i & 0xff))
- {
- Printf("SDRAM Test Fail: %x != %x, ", i, *pbTemp);
- Printf("addr = 0x%x\n", pbTemp);
- }
- }
打印出来的结果：
SDRAM Test Fail: 0 != 2, addr = 0xc0000000
SDRAM Test Fail: 1 != 3, addr = 0xc0000001
总是第0，1字节是正确的，第2，3字节错误。
但是换一种写法：
- *pbAddr = 0x00;
- *(pbAddr + 1) = 0x1;
- *(pbAddr + 2) = 0x2;
- *(pbAddr + 3) = 0x3;
- *(pbAddr + 1024) = 0xA5;
- *(pbAddr + 1024 + 1) = 0x5A;
- Printf("[%x] = 0x%x\n", (uint32_t)pbAddr, *pbAddr);
- Printf("[%x] = 0x%x\n", (uint32_t)(pbAddr + 1), *(pbAddr + 1));
- Printf("[%x] = 0x%x\n", (uint32_t)(pbAddr + 2), *(pbAddr + 2));
- Printf("[%x] = 0x%x\n", (uint32_t)(pbAddr + 3), *(pbAddr + 3));
- Printf("[%x] = 0x%x\n", (uint32_t)(pbAddr + 1024), *(pbAddr + 1024));
- Printf("[%x] = 0x%x\n", (uint32_t)(pbAddr + 1024 + 1), *(pbAddr + 1024 + 1));
[c0000000] = 0x0
[c0000001] = 0x1
[c0000002] = 0x2
[c0000003] = 0x3
[c0000400] = 0xa5
[c0000401] = 0x5a
结果是对的。
| 
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