No Serial Communication - Intermec EasyCoder PF2i Service Manual

15.9 No Serial Communication

Intermec EasyCoder PF2i, PF4i, and PF4i Compact Industrial—Service Manual
Description:
The following actions are valid for the standard serial interface "uart1:"
fi tted on the CPU board and to some extent also to any other serial inter-
faces on optional interface boards. Also see Chapter 15.8.
Possible Causes and Suggested Remedies:
• Communication setup mismatch.
- Press the <i/F5> key or enter the Setup Mode to check that the
printer and host are set for the same communication parameters,
such as baud rate, parity, character length, stopbits, new line and
handshaking. It is stongly recommended to use some kind of
handshaking, for example XON/XOFF or RTS/CTS.
• Damaged RS-232 driver circuit.
- With the aid of an oscilloscope, or some kind of line analyzer ("break-
out box"), verify that the interface signals to and from the CPU board
are correct. The RS-232 driver (U61) could have been damaged as a
result of voltage transients from the interface, necessitating the CPU
board to be replaced. Repeated damage is an indication of insuffi cient
cable screening, or the electrical environment being too noisy.
• Circuits or straps on an optional interface board missing or fi tted
incorrectly.
- See confi guration instructions in Chapter 14.
• No supply voltage.
- Verify that the +3.3VDC and +5VDC voltages are present (see Chap-
ter 13.4).
• No external +5VDC.
- The printer supplies max. 500 mA. The current is automatically
switched off at higher loads. Check the consumption of the con-
nected device.
- The switch (RP60 on the CPU board; IC9 on the Industrial Interface
Board and the Double Serial Interface Board) may be out of range
and need to be replaced.
• Too long communication cables.
- RS-232
- RS-422 max. 1,200 m (4,000 ft).
- RS-485 max. 1,200 m (4,000 ft).
- Current Loop
Chapter 15—Troubleshooting
max. 10-15 m (33-49 ft).
max. 500 m (1,500 ft).
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