Fairlight CVI, Руководство пользователя

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RS232 P O R T C O N T R O L U P DAT E
This section lists the new RS232
"@"
comma nds. The RS232
con trol system is functionally the same as under Revision
5B
software exceptfor t w o importa n t changes:
1.
The CVI now trans m i ts and receives an eight-bit data word.
This change has been made to allow the connection of the
external G raphics Pad and QWERTY keyboard op tions. All
computer by tes sent to the CVI MUST have the most significant
b i t set to zero (standard ASCII), otherw ise t he received data w i l l
be m isused.
2. RS232
"
@
"
commands will now be recognised only when the
CVI is not displaying men us. Characters received w h i l e the m e n u s
a r e displayed are u s e d for m a k i n g menu selections.
Rev
7
Data Transfer Commands
Save Font
Command: S F
T h i s instructs t h e CVI to transmit t h e d a ta contained in t h e
User Defined Font. The amount transmitted varies according t o
the size o f t h e f o n t resident in the font a t t h e time, although a
typical size would be 6000 characters. The data consists of ASCII
cha racters comprising hexadecima l b ytes. This command is used in
conjunction with Load Font.
Load F ont
Command: LF
The User Defined Fon t may be loaded from a font saved with
the Save Font command. The data (two ASCII cha racters per
byte) will be written into the User Font data area, where they
will be in terpreted as font informa tion. The User Font will be
cleared to null cha racters if Load Font is used to recei ve data that
could not be a valid font. This will happen i f the data from a
Save Font comma n d is somehow corru pted. The
CVI
rema i n s i n
L o a d F o n t
mode until either t h e User Font i s full (about 4000
bytes) or an
@
cha racter is received, indicating the start of
a n o t h e r command.
R E V .
7 SOFTWAR E UPDATE - 31