parameter COUNT_BITS = 26;错误
时间: 2023-08-26 11:03:54 浏览: 36
在 Verilog 中,parameter 的定义语法格式为: `parameter [type] name = value;`,其中 type 是可选的类型说明符,name 是参数名称,value 是参数的值。在你提供的代码中,错误出在将 `COUNT_BITS` 作为类型说明符来使用,实际上 `COUNT_BITS` 应该是参数的名称。因此,你可以尝试使用以下代码来定义 parameter:
```
parameter COUNT_BITS = 26;
```
这将定义一个名为 `COUNT_BITS` 的参数,它的值为 26。如果你还有其他疑问或问题,请随时提出。
相关问题
vm.admin_reserve_kbytes = 8192 vm.block_dump = 0 vm.compact_unevictable_allowed = 1 vm.dirty_background_bytes = 0 vm.dirty_background_ratio = 10 vm.dirty_bytes = 0 vm.dirty_expire_centisecs = 3000 vm.dirty_ratio = 20 vm.dirty_writeback_centisecs = 500 vm.dirtytime_expire_seconds = 43200 vm.drop_caches = 3 vm.extfrag_threshold = 500 vm.hugepages_treat_as_movable = 0 vm.hugetlb_shm_group = 0 vm.laptop_mode = 0 vm.legacy_va_layout = 0 vm.lowmem_reserve_ratio = 256 256 32 1 vm.max_map_count = 65530 vm.memory_failure_early_kill = 0 vm.memory_failure_recovery = 1 vm.min_free_kbytes = 67584 vm.min_slab_ratio = 5 vm.min_unmapped_ratio = 1 vm.mmap_min_addr = 65536 vm.mmap_rnd_bits = 28 vm.mmap_rnd_compat_bits = 8 vm.nr_hugepages = 0 vm.nr_hugepages_mempolicy = 0 vm.nr_overcommit_hugepages = 0 vm.numa_stat = 1 vm.numa_zonelist_order = Node vm.oom_dump_tasks = 1 vm.oom_kill_allocating_task = 0 vm.overcommit_kbytes = 0 vm.overcommit_memory = 0 vm.overcommit_ratio = 50 vm.page-cluster = 3 vm.panic_on_oom = 0 vm.percpu_pagelist_fraction = 0 vm.stat_interval = 1 vm.swappiness = 60 vm.user_reserve_kbytes = 131072 vm.vfs_cache_pressure = 100 vm.watermark_scale_factor = 10 vm.zone_reclaim_mode = 0
这是一个包含多个与虚拟内存相关的系统参数的列表。以下是其中一些参数的解释:
- `vm.max_map_count`:最大映射数量,限制了内存中可以同时映射的页面数量,从而影响了缓存的大小。
- `vm.dirty_background_bytes` 和 `vm.dirty_background_ratio`:脏页的阈值,当脏页的数量超过该阈值时,系统会开始写回脏页。
- `vm.dirty_bytes` 和 `vm.dirty_ratio`:系统允许脏页占用的内存大小的上限。
- `vm.min_free_kbytes`:系统保留的空闲内存的大小,当空闲内存低于该值时,系统会开始清理缓存。
- `vm.swappiness`:控制系统在内存不足时使用交换空间的程度,该参数的值越高,系统越可能使用交换空间。
你可以使用 `sysctl` 命令来修改这些参数的值,具体的命令如下:
```
sysctl -w <parameter>=<value>
```
其中 `<parameter>` 表示参数名,`<value>` 表示你希望设置的值。请注意,该命令的修改是临时的,如果你想要永久生效,需要将修改写入到 `/etc/sysctl.conf` 配置文件中。
if ((err = snd_pcm_hw_params(capture_handle, hw_params)) < 0) { printf("Error setting parameters: %s\n", snd_strerror(err)); return 1; } snd_pcm_hw_params_free(hw_params); unsigned int frames_per_period = 2048; snd_pcm_uframes_t period_size = frames_per_period * CHANNELS * 2; snd_pcm_uframes_t buffer_size = period_size * 2; if ((err = snd_pcm_set_params(capture_handle, FORMAT, SND_PCM_ACCESS_RW_INTERLEAVED, CHANNELS, rate, 1, frames_per_period)) < 0) { printf("Error setting parameters: %s\n", snd_strerror(err)); return 1; } FILE *file = fopen(argv[1], "wb"); if (!file) { printf("Error opening file for writing!\n"); return 1; } uint32_t chunk_size = 0; uint32_t subchunk_size = 16; uint16_t audio_format = 1; uint16_t num_channels = CHANNELS; uint32_t sample_rate = rate; uint32_t byte_rate = (rate * CHANNELS * 2); uint16_t block_align = (CHANNELS * 2); uint16_t bits_per_sample = 16; uint32_t data_size = 0; fwrite("RIFF", 1, 4, file); fwrite(&chunk_size, 4, 1, file); fwrite("WAVE", 1, 4, file); fwrite("fmt ", 1, 4, file); fwrite(&subchunk_size, 4, 1, file); fwrite(&audio_format, 2, 1, file); fwrite(&num_channels, 2, 1, file); fwrite(&sample_rate, 4, 1, file); fwrite(&byte_rate, 4, 1, file); fwrite(&block_align, 2, 1, file); fwrite(&bits_per_sample, 2, 1, file); fwrite("data", 1, 4, file); fwrite(&data_size, 4, 1, file); uint16_t buffer[frames_per_period * CHANNELS]; while (1) { int n = snd_pcm_readi(capture_handle, buffer, frames_per_period); if (n < 0) { printf("Error reading from PCM device: %s\n", snd_strerror(n)); break; } fwrite(buffer, 2, n * CHANNELS, file); data_size += n * CHANNELS * 2; } uint32_t file_size = data_size + 36; fseek(file, 4, SEEK_SET); fwrite(&file_size, 4, 1, file); fseek(file, 40, SEEK_SET); fwrite(&data_size, 4, 1, file); fclose(file); snd_pcm_close(capture_handle); 加上注释
/*
这段代码是一个录音程序,使用 ALSA 库进行音频捕获,将捕获到的音频写入到一个 WAV 文件中。
在程序中,首先进行 ALSA 库的初始化,然后设置音频捕获参数,包括采样率、声道数、采样大小等。
然后打开一个 WAV 文件,写入 WAV 文件头部信息,开始捕获音频并将捕获到的音频数据写入到 WAV 文件中。
最后,关闭 WAV 文件和 ALSA 库。
*/
// 引入 ALSA 库的头文件
#include <alsa/asoundlib.h>
int main(int argc, char **argv) {
// 定义 ALSA 相关的变量
snd_pcm_t *capture_handle;
snd_pcm_hw_params_t *hw_params;
int err;
// 打开默认音频捕获设备并进行初始化
if ((err = snd_pcm_open(&capture_handle, "default", SND_PCM_STREAM_CAPTURE, 0)) < 0) {
printf("Error opening PCM device: %s\n", snd_strerror(err));
return 1;
}
// 申请 ALSA 配置参数结构体,进行初始化
if ((err = snd_pcm_hw_params_malloc(&hw_params)) < 0) {
printf("Error allocating hardware parameter structure: %s\n", snd_strerror(err));
return 1;
}
if ((err = snd_pcm_hw_params_any(capture_handle, hw_params)) < 0) {
printf("Error initializing hardware parameter structure: %s\n", snd_strerror(err));
return 1;
}
// 设置音频捕获参数
unsigned int rate = 44100;
int CHANNELS = 2;
if ((err = snd_pcm_hw_params_set_access(capture_handle, hw_params, SND_PCM_ACCESS_RW_INTERLEAVED)) < 0) {
printf("Error setting access type: %s\n", snd_strerror(err));
return 1;
}
if ((err = snd_pcm_hw_params_set_format(capture_handle, hw_params, SND_PCM_FORMAT_S16_LE)) < 0) {
printf("Error setting sample format: %s\n", snd_strerror(err));
return 1;
}
if ((err = snd_pcm_hw_params_set_channels(capture_handle, hw_params, CHANNELS)) < 0) {
printf("Error setting channel count: %s\n", snd_strerror(err));
return 1;
}
if ((err = snd_pcm_hw_params_set_rate_near(capture_handle, hw_params, &rate, 0)) < 0) {
printf("Error setting sample rate: %s\n", snd_strerror(err));
return 1;
}
if ((err = snd_pcm_hw_params_set_period_size_near(capture_handle, hw_params, &frames_per_period, 0)) < 0) {
printf("Error setting period size: %s\n", snd_strerror(err));
return 1;
}
if ((err = snd_pcm_hw_params_set_buffer_size_near(capture_handle, hw_params, &buffer_size)) < 0) {
printf("Error setting buffer size: %s\n", snd_strerror(err));
return 1;
}
if ((err = snd_pcm_hw_params(capture_handle, hw_params)) < 0) {
printf("Error setting parameters: %s\n", snd_strerror(err));
return 1;
}
// 释放 ALSA 配置参数结构体
snd_pcm_hw_params_free(hw_params);
// 计算每个周期的帧数和缓冲区大小
unsigned int frames_per_period = 2048;
snd_pcm_uframes_t period_size = frames_per_period * CHANNELS * 2;
snd_pcm_uframes_t buffer_size = period_size * 2;
// 设置音频捕获参数
if ((err = snd_pcm_set_params(capture_handle, SND_PCM_FORMAT_S16_LE, SND_PCM_ACCESS_RW_INTERLEAVED, CHANNELS, rate, 1, frames_per_period)) < 0) {
printf("Error setting parameters: %s\n", snd_strerror(err));
return 1;
}
// 打开要写入的 WAV 文件
FILE *file = fopen(argv[1], "wb");
if (!file) {
printf("Error opening file for writing!\n");
return 1;
}
// 写入 WAV 文件头部信息
uint32_t chunk_size = 0;
uint32_t subchunk_size = 16;
uint16_t audio_format = 1;
uint16_t num_channels = CHANNELS;
uint32_t sample_rate = rate;
uint32_t byte_rate = (rate * CHANNELS * 2);
uint16_t block_align = (CHANNELS * 2);
uint16_t bits_per_sample = 16;
uint32_t data_size = 0;
fwrite("RIFF", 1, 4, file);
fwrite(&chunk_size, 4, 1, file);
fwrite("WAVE", 1, 4, file);
fwrite("fmt ", 1, 4, file);
fwrite(&subchunk_size, 4, 1, file);
fwrite(&audio_format, 2, 1, file);
fwrite(&num_channels, 2, 1, file);
fwrite(&sample_rate, 4, 1, file);
fwrite(&byte_rate, 4, 1, file);
fwrite(&block_align, 2, 1, file);
fwrite(&bits_per_sample, 2, 1, file);
fwrite("data", 1, 4, file);
fwrite(&data_size, 4, 1, file);
// 读取音频数据并写入 WAV 文件
uint16_t buffer[frames_per_period * CHANNELS];
while (1) {
int n = snd_pcm_readi(capture_handle, buffer, frames_per_period);
if (n < 0) {
printf("Error reading from PCM device: %s\n", snd_strerror(n));
break;
}
fwrite(buffer, 2, n * CHANNELS, file);
data_size += n * CHANNELS * 2;
}
// 计算文件大小并更新 WAV 文件头部信息
uint32_t file_size = data_size + 36;
fseek(file, 4, SEEK_SET);
fwrite(&file_size, 4, 1, file);
fseek(file, 40, SEEK_SET);
fwrite(&data_size, 4, 1, file);
// 关闭 WAV 文件和 ALSA 库
fclose(file);
snd_pcm_close(capture_handle);
return 0;
}