Feature 5019-46 - Elapsed Time Clock; Feature 5003-46 - Direct Control; Feature 5040 Selector Channel; Feature 5041- Selector Channel - RCA 70/46 Reference Manual

Operational
Characteristics
(Cont'd)
FEATURE 5019-46
ELAPSED TIME
CLOCK
Operational
Characteristics
FEATURE 5003-46
DIRECT CONTROL
Operational
Characteristin
FEATURE 5040
SELECTOR CHANNEL *
FEATURE 5041
SELECTO'R CHANNEL *
FEATURE 5042
SELECTOR CHANNEL
*
Optional Features
When an elapsed time clock interrupt occurs, the clock may have been
decremented several times before the interrupt takes effect, depending on
the execution time of the current instruction.
• This feature provides an elapsed time clock with a greater resolution
than the 5002-46 clock. The 5019-46 clock is decremented at a 1000-
cycle rate.
• The elapsed time clock count is performed by decrementing the elapsed
time clock word at main memory location 80. The word is decremented
by 4Dlfi every 1002 microseconds. When the clock count word changes from
positive to negative, if the applicable program mask bit is set, a program
interrupt occurs.
• The Direct Control feature enables one 70/46 processor program to
directly signal the programs of from one to five other processors over an
interface independent of the input/output channels. The processors directly
connected by this feature may be remotely located up to 500 cable feet
from the transmitting processor.
• Two additional privileged instructions are provided with this option,
Write Direct and Read Direct, which initiate the transfer of one byte of
control information between processor memories, and which signal the
opposite unit (by external interrupt) upon execution of an instruction.
This feature can also initiate initial program loading in a remote
processor which is in a stopped state. In this case, the Load Unit Switches
on the console of the processor being signaled specify the device from
which the loading is to occur and the information byte is ignored.
• This feature provides two enhanced selector channels for a system
maximum of 12 I/O Trunks and the Console Trunk.
• This features provides three enhanced selector channels for a system
maximum of 14 I/O Trunks and the Console Trunk.
• This feature provides four enhanced selector channels for a system
maximum of 16 I/O Trunks and the Console Trunk.
*
Only one feature (5040,5041
01'
5042) is permitted on a system.
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