HP 3562A, Service Manual

Page: 354 / 570

MOD E L 3S62A
I RQT5 L
I RQT6L
KYB R D L
LCNV
LDO to LD1 5
LDCH1 L
LDCH 2 L
LDSRCL
C I RCU IT D E SC R I PT I O N S
I NTE RRU PT R E Q U E ST 5
Active Low
I nterrupt request l ine from the A6 Digital Filter Controller to the A2
System C PU . This is an open col lector signal.
I NTERRU PT R E Q U EST 6
Active Low
I nterrupt request l ine from the AB G lobal RAM to the A2 System CPU.
This is an open col lector signal.
K EYBOARD
Active Low
S ignal from the A2 System C PU which selects the A1 S Keyboard. The
system processor uses this l i ne along with A1 L and A2 L to add ress the
keyboard .
LOCAL AID CO NV E RT
(A32, A34 TP606)
This signal is used by the A32 ADC 1 and the A34 ADC 2. The ADC
control ler sends this signal to the A/D converter IC to start converti ng.
When both assembl ies are installed, this signal also goes to the
A32 ADC 1 assembly's AID converter le.
LOCAL DATA BUS
These bidirectional data l ines are used by the AS Digital Fi lter and
the A6 Digital Filter Control ler. Du ring a AS Digital F ilter read/write
operation, these data l ines are the inverted version of the system data
bus.
LOAD CHAN N E L 1
LOAD CHAN N E L 2
Active Low
Signal from the A1 Digital Source that latches command data word
G-JTLD into the A33, A35 i nput assembi ies and the A32, A34 ADC
assemblies.
Active ow
Signal from the A2 System CPU indicati ng data is transferri ng on the
lower half of the system data bus (DO to D7). When LDSL goes low
for a read cycle, the A2 System CPU is expecting val id data to be placed
on the lower half of the data bus. I n the write cycle a low on LDS L
indi cates there is val id data on the lower half of the system d ata bus.
LOAD ANALOG SOURC E
Active Low
Signal from the A1 Digital Sou rce that latches comm and data word
CNTLD into the A30 analog sou rce's sh ift register./
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