Sundance SMT128 - Manual (Page 7)

Preliminary Page 7 of 15 SMT128 User Manual
D0 -> logic 1 = Watchdog is reset using a write to the WDOG RST register.
At reset the value of this signal is ‘0’ i.e. internal oscillator is selected.
DIGIN Register
There are 22 digital input lines connected to the DIN connector PL1.
This is a Read-only register and when read returns the current value on DigIn signals
as illustrated below.
D21 D20 D19 D18 D17 D16 D15 D14 D13 D12 D11
DigIn22 DigIn21 DigIn20 DigIn19 DigIn18 DigIn17 DigIn16 DigIn15 DigIn14 DigIn13 DigIn12
D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0
DigIn11 DigIn10 DigIn9 DigIn8 DigIn7 DigIn6 DigIn5 DigIn4 DigIn3 DigIn2 DigIn1
DIGOUT Register
There are 8 digital output lines, which are connected to the DIN connector PL1.
Each output can be set to the desired logic level by writing to this register using the
Global Bus data bits illustrated below.
D7 D6 D5 D4 D3 D2 D1 D0
DigOut8 DigOut7 DigOut6 DigOut5 DigOut4 DigOut3 DigOut2 DigOut1
VSTATUS Register
When Reading this register the following values are read.
D7 D6 D5 D4 D3 D2 D1 D0
X X X S0INT1 S0INT0 TERMINAL Addr1 Addr0
Addr0, Addr1 -> Board address, reflects the state of the Addr0 and Addr1 signals
on the PL1 connector.
TERMINAL -> When a VT100 terminal, or compatible, is connected to the front
panel this bit is logic ‘1’.