Sam4s ER-280 SERIES - RS-232 C & USB Serial I;F Problem

5. Troubleshooting
SAM4S ER-280 SERIES 5-7
5-7 RS-232C & USB Serial I/F Problem
End
RS-232C Problem
Loop Back
Failure?
Y
N
1. Perform the “SELF TEST” in the S-MODE using the Loop
Back test Connector.
2. Check the connection of the RS-232C Connector and Loop
Back Connector.
3. Check the TXD,RXD, DTR, DSR Pin on CPU.
4. Check the MAX232 Driving Chip and related Circuit on
Serial I/F B’D.
Communication
Failure?
1. Check the connection of the RS-232C and Other side.
2. Check the I/F Cable whether it is open or short.
3. Check whether Signal is affected by the Cable Noise.
N
H/W Handshake
Ok?
Y
Y
1. Check the connection of the H/W handshaking Line and Other
side
2. Check the I/F Cable whether it is open or short.
3. Confirm the H/W handshaking Protocol.
N
End
USB Problem
Loop Back
Failure?
Y
N
1. Perform the “SELF TEST” in the S-MODE using the PC
2. Check the connection of the USB Cable
3. Check the USB_D+,USB_D- signal on Serial B’D.
4. Check the related Circuit and pattern on Serial B’D.
5. Check the USB’s Clock.(6MHz) on Main B’D.
6. Check the USB Driving Chip and related Circuit on Main B’D.
Communication
OK?
1. Check the connection of the USB and Other side.
2. Check the USB Version. This Product supports USB 1.1 Version.
3. Check whether Signal is affected by the Cable Noise.
Y
N