Beehive International B102 Service Manual page 96

PROGRAMMABLE LOGIC ARRAY OUTPUTS
INSTRUCTION
GROUP 1
load REG
deer BCURL
deer BCURP
set BEEP
clear REG
deer CURP 2
incr ROLL
OUTPUT
87654321
-A...AAA
-A...AA-
-A...A-A
-A...A—
-A...-AA
-A...-A-
-A...—A
GROUP 2
FORMAT clock -AAAA.
PROTECT clock -AAA-.
KB CONTROL clock -AA-A.
BLINK clock -AA—.
start TIME -A-AA.
DESCRIPTION
loads REG1 with byte from memory, REG1 byte shifted to REG2
decrements the stored cursor count, underflows when on proper line,
decrements the stored position count underflows when on proper char
acter position. No action unless BCURL has underflowed, indicating
that the cursor is on the proper line.
activates the one-shot controlling the beeper.
clears REG2 to a null code and REG1 to a space code.
used to move the cursor to the last position of a line (CPC=79).
increments the ROLL counter which causes the data on the screen to shift
up one character line. The top line goes to the bottom.
issues a clock pulse to the FORMAT flip-flop. Whether the flop will "set" or
"clear" is controlled by the LS8 of the SEQ counter.
issues a clock pulse to the PROTECT flip-flop. Whether the flop will "set"
or "clear" is controlled by the LSB of the SEQ counter.
Issues a clock pulse to the KEYBOARD DISABLE flip-flop. Settingor clearing
is controlled by the LSB of the SEQ counter.
issues a clock pulse to the BLINK flip-flop. Setting or clearing is controlled
by the LSB of the SEQ counter.
this command is issued when the 30 millisecond timeout is desired. The
CARRY input to the PLA is used to sense the timeout.
NOTE: GROUP 1 and GROUP 2 instructions can be combined to accomplish two operations in the same instrubtion time. If only one
instruction isdesired, the undesignated bitsshould be programmed to **—' s ". (e.g.. clear REG alone is—A —AA; clear REG
and start TIME is —A—AA—AA.)
GROUP 3
Clear BCURL
—...aaa
ENAUXSEND —...AA-
load UART
—...a-a
clear BUFFER —...A—
clear CURL
—.,._aa
clear CURP —...-A-
WRITE
—...—A
GROUP 4
incr CURL
—aaa...
deer CUPL —AA-...
load CURL
—A-A...
incr CURP —A—...
deer CURP
AA...
load CURP
A-...
load BCUR
A...
NOTE: 1.
2.
clears the character line portion of the stored cursor location. This indicates
that the cursor is on the same line as the originally stored cursor line.
this command enables transmission out the AUXILIARY PORT and disables
transmission of data out the MAIN I/O PORT.
loads the UART transmitter holding reg with the contents of the bus. The
loadingactually takes place on the next instruction cycle.
clears the input buffer to a null code.
clears the cursor line reg (sends the cursor to the top line).
clears the cursor position reg (sends the cursor to the beginning of the line),
writes the bus data into the refresh memory.
moves the cursor down one line (increments the CURL reg).
moves the cursor up one line Recrements the CURL reg).
subtracts octal 40 from the contents of the bus and loads the CURL reg.
advances the cursor once (increments the CURP reg).
backspaces the cursor once (decrements the CURP reg).
subtracts octal 40 from the contents of the bus and loads the CURP reg.
saves the current cursor line count and cursor position count in BCURL
and BCURP, respectively.
Theexecution of GROUP 3 instructions LOAD UART. CLEAR BUFFER. CLEAR CURU and CLEAR CURP actually takes place
during the cycle following the issuing of the instruction.
GROUP 3 and GROUP 4 instructions can be combined to accomplish two operations in the same instruction time. If only
one instruction is desired, the undesignated bits should be programmed with —'s.
C-2