if(ret == 0) { return AT_CSCS_ERROR; } ret = UART1_Send_AT_Command("AT+CMGS=\"18759493018\"",">",3,50);
时间: 2023-11-07 19:05:20 浏览: 43
if(ret == 0) { return AT_CSCS_ERROR; }
// If the previous command (AT+CSCS) did not return success, return an error code
// indicating that there was an error with the character set.
ret = UART1_Send_AT_Command("AT CMGS=\"18759493018\"",">",3,50);
// Send the AT command to send an SMS message to the phone number "18759493018".
// Wait for a '>' character response from the modem, with a timeout of 50 milliseconds
// and a maximum of 3 retries.
// If the command was successful, ret will be set to a non-zero value.
// If there was an error, ret will be set to 0.
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解释这段代码if(ret == 0) { return AT_CSCS_ERROR; } ret = UART1_Send_AT_Command("AT+CMGS="18759493018"",">",3,50);
这段代码的意思是,首先判断变量ret是否等于0,如果等于0,则返回错误码AT_CSCS_ERROR;如果不等于0,则执行下一步操作。下一步操作是通过UART1串口发送AT命令"AT CMGS="18759493018"",并等待接收到">"符号,最多等待3次,每次等待时间为50毫秒。发送AT命令的目的是向号码为18759493018的手机发送短信。
if (0) { ret = pl_rs485_send_data_fast(pdata, len); } else { ret = pl_rs485_send_data_z4k_old_slow(pdata, len); }
根据代码片段来看,这是一个条件语句。如果条件 `(0)` 成立(即为真),那么会执行 `pl_rs485_send_data_fast(pdata, len)` 函数;否则,会执行 `pl_rs485_send_data_z4k_old_slow(pdata, len)` 函数。在这段代码中,条件 `(0)` 永远不会成立,因为 `0` 被视为假值。所以,实际上会执行 `pl_rs485_send_data_z4k_old_slow(pdata, len)` 函数。
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