5 register map – Measurement Computing CIO-CTRxxHD User Manual
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5 REGISTER MAP
5.1
CONTROL & DATA REGISTERS
The CIO-CTR10HD is composed of two AM9513 counter timer chips, the
CIO-CTR20HD is composed of four. Each 9513 contains five counters of 16 bits
each. Associated with each counter are an input source, a count register, a load
register, a hold register, an output and a gate. The 9513 is extremely flexible and this
flexibility can make it a challenge to program the chip directly.
Unlike an Intel 8254 which has a single source, single gate and unique I/O address for
each counter, the 9513 is fully programmable and any counter may be internally
connected to any gate and receive it's counts from a number of sources. In addition,
each counter does not have a unique I/O address. The 9513 takes only two address
per chip, one of which is a data path to the counter's load and hold registers.
There is no 9513 register information in this manual. Those wishing to know more
about the AM9513 and its programming should request the manual from our technical
support group. As of this writing there is no charge for the manual.
We strongly suggest that you use the Universal Library, rather than resort to
programming the 9513 directly. It is difficult to program and because programming
support is available through the Universal Library, we cannot help with other 9513
programming
The CIO-CTR##HD is an I/O mapped expansion board. The CIO-CTR20HD
occupies eight I/O addresses and the CIO-CTR10HD occupies four addresses.
The first address, or BASE ADDRESS, is determined by setting a bank of switches on
the board.
Most of the functions that this board is capable of performing can be acheived using
the Universal Library. Unless you have a good reason for direct register
manipulation, we suggest you use the Universal Library.
The register descriptions follow the format:
A0
A1
A2
A3
A4
A5
A6
A7
0
1
2
3
4
5
6
7
Where the numbers along the top row are the bit positions within the 8-bit byte and
the numbers and symbols in the bottom row are the functions associated with that bit.
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