User`s manual

Register-Based Programming 135
Status/Control Register
Bits Defined:
Resetting the Module Follow this procedure to reset the module.
• Set the SYSFAIL bit to “1”.
• Set the R (reset) bit to “1”.
• Wait 10 nanoSeconds.
• Set both bit 0 and bit 1 to “0”
Disable/Enable Interrupts To disable the interrupt generated when channels are opened or closed, write
a “1” to bit 6 of the Status/Control Register (base + 04
h
). Refer to your
command module's operating manual before disabling the interrupt.
Interrupts must be enabled in order to use the module’s driver.
Reading the
Status/Control Register
Module Status
Each relay requires about 5 ms execution time. During this period, the relay
is “busy”. Bit 7 of this register informs the system of a busy condition. The
interrupt generated after a channel has been closed can be disabled. Bit 6 of
this register is used to inform the user of the interrupt status.
As an example, if the Status Register (base + 04
h
) returns “3EEE
h
(0011111011101110)” the multiplexer module is not busy (bit 7 set), the
module interrupts are disabled (bit 6 set), and interrupt level is set to 1 (bits
10, 9, 8 = 001).
*WRITE BITS (Control Register)
bit 0 R Writing a “1” to bit 0 resets the module to the power-on state (all channels open). Allow
a 5 mS delay, then you must set bit 0 back to “0” before the multiplexer will resume
normal open/close operations.
bit 1 SYSFAIL Writing a “1” to bit 1 inhibits the front panel SYSFAIL error LED.
bit 6 D Writing a “0” to this bit enables the interrupts. Writing a “1” to this bit disables the
interrupts.
bits 10, 9, 8 Interrupt
level
Write to bits 8, 7, and 6 to set the module’s interrupt level. You can write the bits with
001, 010, 011, 100, 101, 110, 111 to set the interrupt level equal to 1, 2, 3,..., 7. Level 1
is the default value.
**READ BITS (Status Register)
bit 0 R “1” = a soft reset initiated; module switching disabled. “0” = module operation enabled.
bit 1 SYSFAIL “1” = front panel SYSFAIL LED is inhibited. “0” = SYSFAIL LED enabled.
bit 7 B Busy Status: “0” = busy (relay is opening/closing);
“1” = not busy (relay is open/closed).
bit 6 D “1” = interrupt disabled; “0” = interrupt enabled
bits 10, 9, 8 Interrupt
level
The returned value indicates the current interrupt level of the multiplexer (1 - 7).
bit14 M MODID bit; value “0” indicates that this module has been selected.