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1.
Congratulations!
Thank you for purchasing the AT Keyboard Interface,
another one of the fine products offered by Cloud-9. This
product was designed to be used with the Radio Shack TRS-
80 Color Computer 2, and the Tandy Color Computer 3.
The interface connects to the CoCo via the standard
keyboard connector. Because it emulates a real CoCo
keyboard at the hardware level, no special software drivers
are required. This also ensures the PC keyboard will work
with all software, even those programs which access the
hardware directly (many do). Besides providing ordinary
keyboard facilities, the interface also sports a few extra
features. The extra keyboard keys can be used as
programmable macro keys. The macros can be re-defined at
any time using the keyboard, and are stored indefinitely. The
ability to reset the computer via the
CTRL ALT DELETE
key
sequence is also provided to perform a CoCo RESET. This
interface can connect to the CoCo 2 and 3 and any 101-key
PC "AT" keyboard. Please note that the older 84-key XT
keyboards are not supported.
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the recording. The recording will also stop if the sequence
exceeds 32 bytes in length. To erase a macro, simply press
shift macrokey twice to record a null macro. To play a
macro, press macrokey. The keys are played back at a
predetermined rate which cannot be adjusted. The playback
is not affected by the state of the keyboard caps lock when
invoked; the state of the keyboard caps lock is significant
only when the macro is recorded. In contrast, the state of the
CoCo caps lock does not affect the recording, but it is
significant when the macro is played back. Note that while
recording a macro, it is best to avoid key roll-over in order to
reduce the number of bytes needed to store the macro. Roll-
over occurs when while typing quickly you press a second
key before releasing the first one. Because of how the keys
are stored when a macro is recorded, a two key sequence
without roll-over takes 2 bytes, where as with roll-over, the
same sequence takes 4 bytes.
The 32 byte limit is exceeded much more easily if
overlapping key sequence information is unnecessarily
stored due to roll-over. As a rule of thumb, type slowly when
recording macros.
Keyboard Reset
Another desirable feature of the interface is the ability to
reset the CoCo via the
CTRL ALT DELETE
key combination.
Pressing
SHIFT CTRL ALT DELETE CA
uses the interface to hold
down the CoCo's
CTRL A
nd
ALT
keys while resetting. This is
useful for forcing a cold restart on the CoCo 3.
