Meinberg TCR51USB - Manual (Page 13)

13
Firmware Updates
Whenever the on-board software must be upgraded or modified, the new firmware can
be downloaded to the internal flash memory via the USB connection.
If the button behind a hole in the housing is pressed during the power up, a bootstrap
loader is activated and waits for instructions from the USB. A loader program shipped
together with the file containing the image of the new firmware sends the new firmware
from one of the computer's USB interfaces. The bootstrap loader does not depend on the
contents of the flash memory, so if the update procedure is interrupted, it can easily be
repeated.
The contents of the program memory will not be modified until the loader program has
sent the command to erase the flash memory. So if the button has been pressed
accidentally, the system will be ready to operate again after the computer has been turned
off an the on again.
Technical specification TCR51USB
RECEIVER INPUT: AM-input (SMB-jack):
insulated by a transformer
impedance settable 50
Ω
input signal: 600 mVpp to 8 Vpp (Mark)
other ranges on request
DC Level Shift input (SMB-jack):
insulated by photocoupler
internal series resistance:
220
Ω
maximum forward current: 50 mA
diode vorward voltage:
1.0 V...1.3 V
DECODING: decoding of the following telegrams possible:
IRIG-A133/A132/A003/A002
IRIG-B123/B122/B003/B002
AFNOR NFS 87-500
OPTIONAL
OUTPUTSIGNAL:
PPS-Signal (as TTL-Level or RS232-Level)