Kontron KTA55-pITX - Manual (Page 16)

KTD-S0043-A Page 13 CPLD Interface
KTA55/pITX Software Guide
6 CPLD Interface
Various functions are implemented in the CPLD: e.g. the watchdog. Access to the CPLD register is via an
index-data register pair using only two I/O byte locations (fixed addresses).
Index Register Data Register
0xA80 0xA81
Register overview:
Index Type Reset Function
0x00 RO --- CPLD version register
0x01 RW ---
System control register
Bit 0 Reserved
Bit 1 Reserved
0x02 RO --- Reserved
0x03 RO ---
System status register
Bit 0 Recovery jumper
0 = not active
1 = active
Bit 1 Autostart jumper
0 = active
1 = not active
Bit 2 Reserved
Bit 3 Reserved
Bit 4 Reserved
Bit 5 Last reset caused by watchdog
0 = no
1 = yes
0x04 RO --- Reserved
0xA2 RW 0x00
1)
Watchdog control register
Bit 0 - 1 Watchdog time value
Bit 2 - 3 Reserved
Bit 4 Watchdog time base
0 = seconds
1 = minutes
Bit 5 Reserved
Bit 6 Watchdog control
0 = disabled
1 = enabled
Bit 7 Trigger control
0 = disabled
1 = enabled
0xA3 RO --- Watchdog timer register
Note: 1) Default Setup settings.
6.1 Reserved Bits
Every bit which is marked as Reserved may not be changed. Not observing this hint can in the worst case
lead to system crashes.