Townshend Computer Tools DAT-Link - Page 116

112 Third Party Supp ort
1. Set the RD1x5T for 16-bit digital mode as described above.
2. Start the RD1x5T recording.
3. Run naplay music on the host.
4. After naplay exits, the DAT machine can b e stopp ed.
Note that while data is b eing sent to the RD1x5T, a small decimal point will ash
to the right of the numb er 16 displayed on the VU meter.
It should be noted that the RD1x5T usually uses the two least signicant bits of
the data stream for side information such as the real time clo ck and voice memo.
Arbitrary 16-bit data sent to the RD1x5T will not generally have the correct format
to supp ort this side information. Thus, if a tap e recorded with data from the DAT-
Link +isplayed back with the deck in analog mode, the deck will indicate an error
and default to 2 channel playback at normal speed. There are a numberofways to
make use of this behavior as describ ed in the following sections.
Recording Data with TEAC Format
The teacout program is provided to modify the two least-signicant bits of a data
stream in a manner compatible with that used by the TEAC decks. These two
bits carry the time-co de information, the sp eech memo channel, and other side-
information. The teacout program is describ ed in detail in App endix G. Atypical
use of this program would be to transfer a multi-channel data le to the TEAC
deck. For example,
teacout -n 8 -r 24000 file | naplay
would take the data in le and modify the least-signicant bits to indicate that
the data contains 8 channels sampled at 24,000 samples/second. In this case, the
memo channel would b e silent, but the teacout program has an option to read that
from a le also. Note that the TEAC's sp eed select switchmust be manually set
to match the desired recording speed, the rate specied on the teacout command
line is used only to set the side information and do es not aect the actual recording
speed.
Using 14-bit Data Mode
Another method to record a TEAC tap e with the correct side information is to let
the deck add the extra information while the data is being transferred from the
host computer to the deck. To do this, the deckmust be set into 14-bit data mode.
This is done by following the same instructions as to set it for 16-bit mode, but
using the \ CH. " button instead of the \ /C H " button. In this mode the lower