Elektra CPU User Manual V1.00
Page 20
5. JUMPER SETTINGS
Refer to the ELEKTRA board drawing on page 9 for locations of the configuration items
mentioned here. See page 22 for information on configuration J13 for the data acquisition circuit.
5.1 System Configuration J10
Jumper block
J10
is used for configuration of IRQ levels, wait states, ATX power control, and
CMOS RAM.
Serial Port and A/D IRQ Settings
COM3 may be set to IRQ3, IRQ4, IRQ 5, IRQ 6, or IRQ9. COM4 may be set to IRQ3 or IRQ15.
The A/D circuit may be set to IRQ6, IRQ5, or IRQ4 if COM3 does not use it. In addition, it is
possible to set up all 3 circuits to share IRQs. Note that only 1 device can use the ‘shared’ IRQ at
one time. True IRQ sharing where all 3 devices can run simultaneously is not supported here
except with software driver check. To support true IRQ sharing for all 3 devices for every IRQ call
software drive needs to check the source of the IRQ call and handle appropriately.
ATX Power Control
ELEKTRA must have ATX enabled to function properly. This jumper must be installed for the
board to boot when power is applied.
Erasing CMOS RAM
The CMOS RAM may be cleared with a jumper as shown on the next page. This will cause the
CPU to power up with the default BIOS settings. To clear the CMOS RAM, power down the CPU,
install the jumper as shown, return it to its default position, and then power up again.
Before erasing CMOS RAM, write down any custom BIOS settings you have made!
Default Settings:
ATX enable
Battery enabled
A/D IRQ 5
COM4 IRQ 15
COM3 IRQ 9
