No Serial Communication - Intermec EasyCoder PX4i Service Manual

17.10 No Serial Communication

EasyCoder PX4i and PX6 Service Manual
Description:
The following actions are valid for the standard RS-232 serial interface
("uart1:" in Fingerprint) fi tted on the CPU board and to some extent also
to any other serial interfaces on optional interface boards. Also see Chapter
17.8.
Possible Causes and Suggested Remedies:
• Communication setup mismatch.
- Press the <i> 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 handshak-
ing. It is strongly 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 16.
• No supply voltage.
- Verify that the +3.3 VDC and +5 VDC voltages are present (see
Chapter 15.4).
• No external +5 VDC.
- 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
- RS-485
- Current Loop
Chapter 17 — Troubleshooting
max. 10-17 m (33-49 ft).
max. 1,200 m (4,000 ft).
max. 1,200 m (4,000 ft).
max. 500 m (1,500 ft).
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