VCC
U6: 7408 features an "And" gate.
U6 P1.0 P1.1 1 2 3 4 5 6 7 1A 1B 1Y 2A 2B 2Y GND VCC 4B 4A 4Y 3B 3A 3Y 7408 14 13 12 11 10 9 8 VCC
JP3: 此40脚的连接座与对应40脚的单片机, 可以测量单片机每个脚的电压等信息。
P0.[0..7]
R11,R12: the pack resistors improve the driving ability
R11 8 7 6 5 4 3 2 1 vcc R12 vcc 1 2 3 4 5 6 7 8
B
MAX232: TTL电平转换为RS232电平
MAX232: used to convert the T to the RS232 co TL mpatible
DS1 DS2 DS3 JP12 RESET P1.5 P1.6 P1.7 DS4 DS5 DS6 2 2 2 2 2 2 2 2 1 1 1 1 1 1 1 1 R1 R2 R3 R4 R5 R8 R14 R15 P1.0 P1.1
INT0
P1.2 P1.3
VCC
R1 1,R 12 : 上 拉 电阻 增 强 高 电 平驱 动 力 。
JP3:Be a mirror of the MC this 40-pin port U, co nnected to the 40 pins of the MCU, which used to read the voltage of each pin and m ake other measurements.
XTA L 32.76 8KHZ C12 6pF