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Manual Number: 00650-004-5
Page 3-4
ADIO1600 Manual
Counter/Timer
Three 16-bit Counter/Timers are provided on ADIO1600. Refer to the block diagram for an under-
standing of the counter/timer configuration and to the PROGRAMMABLE INTERVAL TIMER
section for programming and applications.
Counters 1 and 2 are intended for software-programmed, timed A/D start. Counter 0 has its clock
and output lines available on the I/O connector. The gate input for Counter 0 is at digital input IP2.
Clock Frequency Select
The clock for Counter #0 and #1 is a 1 MHZ derived from an on-board crystal oscillator. Counter
#0 also has an external clock input selected under software control (see the SOFTWARE section
for the register address).
Selecting and Setting the Base Address
The following section shows you how to select and set the address.
Selecting a Base Address
You need to select an unused segment of 20 consecutive I/O addresses. The base address will be
the first address in this segment. The base address may be selected anywhere on a 32-bit boundary
within the I/O address range 100-3FF hex providing that it does not overlap with other functions.
The following procedure will show you how to select the base I/O address.
1) Check the tables in Table 3-3 for lists of standard address assignments and then check
what addresses are used by any other I/O peripherals that are installed in your computer.
(Memory addressing is separate from I/O addressing, so there is no possible conflict with any
add-on memory that may be installed in your computer.) We urge that you carefully review the
address assignment table before selecting a card address. If the addresses of two installed
functions overlap, unpredictable computer behavior will result.
2) From this list, (or using the base address function in the A1216EST setup software) select an
unused portion of 20 consecutive I/O address. Note from the tables that the sections 100-1F0,
280-2EF and 330-36F are unused. This address space is a good area to select the base address.
Also, if you are not using a given device listed in the tables, then you may use that base address
as well. For example, since most computers do not have a prototype card installed, then base
address 300 hex is a good choice for a base address.
3) Finally make sure that the base address you have chosen is a multiple of Hex 20. This insures
that your base address is on a 32-bit boundary.
NOTE:
The hexadecimal numbering system is used in this manual for addresses. Data values are in
binary or decimal values, unless marked with a "h" suffix for hexadecimal values.