Measurement Computing STLITE-PCI-8x - Manual (Page 15)

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6.3 EXAMPLE PROGRAMS
Included with the Satellite Monitor are example programs written in C/C++, Visual Basic (v5.0 and later), and
Delphi (v3.0 and later) demonstrating how to use each of the API functions provided by the Satellite Library.
These examples are installed in the subdirectories C, Delphi, and VB of the installation directory.
7 REGISTER MAP
7.1 INTRODUCTION
The STLITE-PCI-8T provides a sets of general-purpose I/O control bits (GPIO0-GPIO3). These bits are
accessed via by the 21150 PCI-PCI bridge chip located on the STLITE-PCI-8T’s backplane. The GPIO bits
interface directly to the serial control bits which are used to configure and control the voltage, temperature and
current measuring A/D converters located within the chassis and on the optional STLITE-PCI-8+ temperature
sensor board.
7.2 SATELLITE 21150 PCI BRIDGE REGISTERS
GPIO OUT Register ( 0x65 offset of PCI Header ) Read/Write
D7 D6 D5 D4 D3 D2 D1 D0
OE X S_CLK SDI OE X S_CLK SDI
GPIO3 GPIO2 GPIO1 GPIO0 GPIO3 GPIO2 GPIO1 GPIO0
This register provides access to the serial data I/O control bits. The STLITE-PCI-8T motherboard provides these
bits for the user to control the precision A/D converters. The converters measure chassis temperatures, voltages
and fan current. Addressing specific A/D converters is accomplished using the GPIO control bits. Refer to the
chip-select lookup table, 6-1 for coding. See the Texas Instruments TLV2548 datasheet for more specific
information concerning the configuration of the A/D converters.
Table 6-1. A/D Select Codes
SDI S_CLK A/D selected Function
Lo Lo A/D_0 Measures voltages, chassis temperature and fan current
Hi Lo A/D_1 Measures temperatures of chassis slots 4-11
The order of operation for programming the A/D converters should include:
1. Selecting the specific A/D converter chip (see chip-select Table 6-1 above).
2. Configuring the A/D converters (see TI TLV2548 datasheet for specifics).
NOTE: The STLITE-PCI-8T motherboard drives the reference input of the two A/D
converters with a precision reference. Attempting to re-configure the A/D converters to use an
internal reference will result in inaccurate results.
3. Read/Write data from or to the A/D converter.
Bits 0-3 of this register operate in a “Write-1-To-Clear” manner. Writing a “1” to any bit in the lower nibble
will drive the corresponding GPIO bit low even if it has been previously programmed as bi-directional. Bits