STC micro U8W - Reference Circuit of U8 W;U8 W-Mini

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STC8H Series Manual
2. After U8W/U8W-Mini is powered on, it is in normal download mode. At this time, press and hold the Key1
(download) button on the tool and do not release it. Press the Key2 (power) button again, and then release the
Key2 (power) button. Then release the Key1 (download) button, U8W/U8W-Mini will enter the USB to serial
port pass-through mode. (Press Key1→ Press Key2 → Release Key2 → Release Key1);
3. The U8W/U8W-Mini tool that enters the pass-through mode is just a simple USB to serial port and does not have
the offline download function. If you need to restore the original functions of U8W/U8W-Mini only need to
press the Key2 (power) button separately again.
3.10 Reference circuit of U8W/U8W-Mini
USB online/offline download board U8W/U8W-Mini provides users with the following common control interfaces:
Pin function
Port
Function description
Power control pin
P2.6
Low effective
Download communication
pin
P1.0
Serial port RXD, connect to the TXD of the target chip
(P3.1)
P1.1
Serial port TXD, connect to RXD of target chip (P3.0)
Programming button
P3.6
Low effective
display
P3.2
LED1
P3.3
LED2
P3.4
LED3
P5.5
LED4
External serial Flash
control pin
P2.4
Flash CE Pin
P2.2
Flash SO Pin
P2.3
Flash SI Pin
P2.1
Flash SCLK Pin
Automatic burning tool
Sorter signal
P3.6
Start signal
P1.5
Completion signal
P5.4
OK signal (good signal)
P3.7
ERROR signal (defective product signal)
Buzzer (BEEP) control
P2.5
High effective (sound at high level)
Reference circuit diagram for power control part:
Reference circuit diagram of Flash control part:
STC Tool Instruction Manual