Wang 5536 - Page 36

3402
Set Internal Clock Rate
Instruction OUT X '11'
The bits/sec rate of the USART's internal clock is set. When asynchronous
transmission is employed, the clock rate divider in the USART Mode Word
must also be set.
Note that when the clock is used to provide a synchronous clock signal by
driving Secondary Request to Send and using a jumper plug to connect it
hack to the USART and concurrently to a directly connected computer or
terminal, the Baud Rate Select Code is different from that used for
asynchronous transmission.
Clear Keyboard Interrupt
Instruction OUT X '12' The keyboard interrupt request is cleared.
Clear Timer Interrupt
Instruction OUT X '13' The interval timer interrupt request is cleared.
Set Secondary Request to Send and Clock Mode
Instruction OUT X '14' BIT
DO
D4
MEANING
SAC
SRS
The modem control signal Secondary Request to Send (SRS) and the Select
Asynchronous Clock bit (SAC) are set at the power up. The source of
transmission timing for the USART is selected by SAC = 0 as the modem
signals, Transmit Signal Element Timing and Receive Signal Element Timing.
Otherwise the USART' s internal clock is selected as the timing source.
When the modem signals are selected as the timing source, the internal
clock drives the modem interface signal, Secondary Request to Send. This
permits asynchronous transmission between the workstation and another
system through a direct cable connection when the appropriate modem
connector jumper plug is installed.
Disable Teleconnnunications Interrupts
Instruction OUT X '16'
The interval timer, transmitter, and receiver interrupts are disabled. The
keyboard interrupt is always enabled and is not affected by this
instruction. When the telecommunications is initially powered on, the
telecommunications interrupts are disabied.
Enable Telecommunications Interrupts
Instruction OUT X '17'
The interval timer, transmitter, and receiver interrupts are enabled.
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