Introduction - If you have any usage issues, please Google them yourself
C programming language based on:
1 hexadecimal byte 0x5a: binary is 01011010B 0x6E is 01,101,110.
2, if a 16-bit binary number assigned to an 8-bit byte variable, it is automatically truncated to the lower 8 bits, while losing a high 8.
3,++ var first expressed by a variable var var-expressed variables minus one.
4, x | = 0x0f expressed as x = x | 0x0f
5, TMOD = (TMOD & 0xf0) | 0x05 said to the variable assignment TMOD low four 0x5, without changing the TMOD high four.
6, While (1) that the statement is infinite, that is an infinite loop. Statement after the semicolon represents the empty loop, that is, { }
Fifth, in a pin-high programming: (eg, P1.3 (PIN4) pin)
# I nclude <AT89x52.h>// The first document in the symbol of single-chip definition of internal resources, which includes P1.3
void main (void)// void that no input parameters, and no function return value, this entry into the microcontroller reset operation