Most built-in types have implementation-defined sizes. The following table lists the amount of storage required for built-in types in Microsoft C++. In particular, long is 4 bytes even on 64-bit operating systems.
Type
Size
bool, char, char8_t, unsigned char, signed char, __int8
This returns the processor’s serial number. The processor serial number was introduced on Intel Pentium III, but due to privacy concerns, this feature is no longer implemented on later models (PSN feature bit is always cleared). Transmeta’s Efficeon and Crusoe processors also provide this feature. AMD CPUs however, do not implement this feature in any CPU models.
For Intel Pentium III CPUs, the serial number is returned in EDX:ECX registers. For Transmeta Efficeon CPUs, it is returned in EBX:EAX registers. And for Transmeta Crusoe CPUs, it is returned in EBX register only.
Note that the processor serial number feature must be enabled in the BIOS setting in order to function.
Processor information that describes the processor features. For an x86 class CPU, the field format depends on the processor support of the CPUID instruction. If the instruction is supported, the property contains 2 (two) DWORD formatted values. The first is an offset of 08h-0Bh, which is the EAX value that a CPUID instruction returns with input EAX set to 1. The second is an offset of 0Ch-0Fh, which is the EDX value that the instruction returns. Only the first two bytes of the property are significant and contain the contents of the DX register at CPU reset—all others are set to 0 (zero), and the contents are in DWORD format.”
SIIM800L 是通过串口用 AT 命令和 ESP32 打交道的，为了便于测试设计如下的测试代码：
#include <Wire.h>
// Set serial for AT commands (to the module)
#define SerialAT Serial1
#define MODEM_RST 5
#define MODEM_PWRKEY 4
#define MODEM_POWER_ON 23
#define MODEM_TX 27
#define MODEM_RX 26
#define I2C_SDA 21
#define I2C_SCL 22
#define LED_GPIO 13
#define LED_ON HIGH
#define LED_OFF LOW
#define IP5306_ADDR 0x75
#define IP5306_REG_SYS_CTL0 0x00
void setup() {
// put your setup code here, to run once:
Serial.begin(115200);
// Set GSM module baud rate and UART pins
SerialAT.begin(115200, SERIAL_8N1, MODEM_RX, MODEM_TX);
delay(1000);
#ifdef MODEM_RST
// Keep reset high
pinMode(MODEM_RST, OUTPUT);
digitalWrite(MODEM_RST, HIGH);
#endif
pinMode(MODEM_PWRKEY, OUTPUT);
pinMode(MODEM_POWER_ON, OUTPUT);
// Turn on the Modem power first
digitalWrite(MODEM_POWER_ON, HIGH);
// Pull down PWRKEY for more than 1 second according to manual requirements
digitalWrite(MODEM_PWRKEY, HIGH);
delay(100);
digitalWrite(MODEM_PWRKEY, LOW);
delay(1000);
digitalWrite(MODEM_PWRKEY, HIGH);
// Initialize the indicator as an output
pinMode(LED_GPIO, OUTPUT);
digitalWrite(LED_GPIO, LED_OFF);
Serial.println("Starting......");
}
void loop() {
if (Serial.available()) { // If anything comes in Serial (USB),
SerialAT.write(Serial.read()); // read it and send it out Serial1
}
if (SerialAT.available()) { // If anything comes in Serial1
Serial.write(SerialAT.read()); // read it and send it out Serial (USB)
}
}
