
FPGA Registers
EPU-4562 Programmer’s Reference Manual
31
AUXMODE2– AUX I/O Mode Register #2
This register defines the interrupt mapping for the AUX GPIOs.
Reset type is Platform.
Table 39: AUXMODE2 - AUX I/O Mode Register #2
Bits
Identifier
Access
Default
Description
7
IRQEN
R/W
0
AUX GPIO interrupt enable/disable:
0 – Interrupts disabled
1 – Interrupts enabled
6-4
IRQSEL(2:0)
R/W
000
AUX GPIO interrupt IRQ select in LPC SERIRQ:
000 – IRQ3
001 – IRQ4
010 – IRQ5
011 – IRQ10
100 – IRQ6
101 – IRQ7
110 – IRQ9
111 – IRQ11
3-0
Reserved
RO
0000
Reserved. Writes are ignored; reads always return 0.
FANCON
–
F
AN
C
ONTROL
R
EGISTER
The fan is always off in any sleep mode. When the processor comes out of sleep this register
must be setup again since it will be reset to default by the platform reset signal. The fan is always
turned “off” in sleep modes.
On other products the FPGA controlled the fan and monitored fan speed. The FPGA on this
products does that as well but the COM Module can also control the fan (either on/off or PWM)
and monitor the fan speed. The FPGA currently only allows the fan to be turned on or off (no
PWM since that requires interleaved fan-speed monitoring). This is the same case with the COM
Module unless a 4-wire fan is used in which case the COM Module can use PWM fan-speed
control and monitor fan speed.
On all FPGA releases after DEV-0.02 (which only support the R1B PCB rev 0.20A or later) the
fan tach signal is monitored by both the FPGA and COM Module all the time (COM_MODE
does not impact this). The only purpose of COM_MODE is to select whether the COM Module
or the FPGA controls the fan on/off (or PWM speed should that be used on the COM Module).
Reset type is Reset.