rtd cpuModules CME34BT, User Manual, Page: 68 / 110

60 CME34BT cpuModule BDM-610000088 Rev A
Clear Register :
A read to this register Clears the IRQs and a write to this register sets the DIO-Compare, DIO- Mask,
DIO-Control, Port 1, and Port 0 to zeros. A write to this register is used to clear the board.
Port 0 Direction Register :
Writing a zero to a bit in this register makes the corresponding pin of the aDIO connector an input.
Writing a one to a bit in this register makes the corresponding pin of the aDIO connector an output.
Mask Register :
Writing a zero to a bit in this register will not mask off the corresponding bit in the DIO-Compare
register. Writing a one to a bit in this register masks off the corresponding bit in the DIO-Compare
register. When all bits are masked off the aDIOs comparator is disabled. This condition means Event
and Match mode will not generate an interrupt. This register is used by Event and Match modes.
Compare Register :
A Read/Write register used for Match Mode. Bit values in this register that are not masked off are
compared against the value on Port 0. A Match or Event causes bit 6 of DIO-Control to be set and if
the aDIO is in Advanced interrupt mode, the Match or Event causes an interrupt.
Table 35 DIO-Control I/O Address EC3h—Read Access
D7 D6 D5 D4 D3 D2 D1 D0
Table 36 DIO-Control I/O Address EC3h—Write Access
D7 D6 D5 D4 D3 D2 D1 D0
Table 37 Multi-Function at Address EC2h 1
1. Contents based on bits D0 and D1 of DIO-Control.
X X X X X X X X
I/O I/O I/O I/O I/O I/O I/O I/O
M7 M6 M5 M4 M3 M2 M1 M0
C7 C6 C5 C4 C3 C2 C1 C0
Strobe 0
Status
0 = no strobe
Digital IRQ Status
0 = no digital interrupt
1 = digital interrupt
Strobe 1
Status
0 = no strobe
Digital IRQ Mode
00 = Disabled
01 = strobe Mode
10 = event mode
11 = match mode
Port 1
Direction
0 = input
Multi-Function
Register Select
00 = clear mode
01 = port 0 direction
10 = mask register
11 = compare register
Multi-Function
Register Select
00 = clear mode
01 = port 0 direction
10 = mask register
11 = compare register
Port 1
Direction
0 = input
Reserved
read/write 00 clear
0 in, 1 out
01 Port 0
direction
0 no mask, 1
mask
10 DIO mask
read/write 11 compare
Digital IRQ Mode
00 = Disabled
01 = strobe Mode
10 = event mode
11 = match mode