ICS Advent WDT-1002, Product Manual

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Manual Number: 00650-009-28 Page 5-4
WDT1000-P Manual
Before the timeout expires, counter 2 must be reloaded:
OUT 2, 100 'Reload counter 2 low byte '100*4.44 mSec.
Temperature Alarm
To test if the internal computer temperature exceeds the preset level, read bit 0 at the Temperature
Alarm register (Watchdog base a 4). Bit 0 will be a “0” if temperature is normal and “1” if
temperature is excessive. Bits 1 through 7 of this register are meaningless.
Serial Output
The serial communications port has its own base address. If that base address is set as COM1 or
COM2, simply follow standard DOS procedures. If serial communications port is NOT set as
COM1 or COM2, follow the NS16450 chip (ACE) specification.
The following code sample is in BASIC and demonstrates the recommended steps to initialize the
NS16450 for normal operation. This sample assumes a base address of 3F8 and the device will be
setup for 9600 baud with an 8-bit, no-parity format. The assumed clock frequency is 1.8432 MHz
and, thus, a divisor of 12 is required. (The divisor is determined by dividing the clock frequency by
16 then by the baud rate).
OUT &H3FC, &H10 'Put into loopback.
OUT &H3FB, &H80 'Select divisor latch.
OUT &H3F8, 12 'Lower half of 9600 baud divisor.
OUT &H3F9, 0 'Upper half of 9600 baud 'divisor.
OUT &H3F8, 3 'Deselect divisor latch, set 8 'bits/1 stop/no
parity.
TMP = INP(&H3F8) 'Read input port.
FOR TMP = 1 TO 2 'Wait for at least two character 'times.
NEXT
TMP = INP(H3F8) 'Read input port a second time.
OUT &H3FC, 1 'Take out of loopback; set "Dir".