User manual
Imagestore HDTV User Manual Overview
Miranda Technologies Ltd Page 99
General Purpose Interface (GPI) ports may be used either to trigger the
execution of a series of Imagestore HDTV internal pre-programmed
commands (input) or to monitor the status of the Imagestore HDTV (output).
The nine GPI ports are identified as GPI 1 through GPI 9. The first seven
ports, GPI 1 through 7, may be configured as either input or output ports
whilst the remaining two, GPI 8 and GPI 9 may only be configured as inputs.
Any GPI, assigned to ‘input’, may have a macro associated with it that
contains up to 2K bytes of command data (approx. 200 commands strings).
When triggered, the commands within the macro execute sequentially. If the
GPI is assigned as an ‘output’, it may only have a single status associated
with it.
Input to GPI
Where a GPI port is used as an input, the command macro is activated when
either, the connection is made (GPI On) or switched off (GPI Off) relative to
the GPI ground pin (pin 13) on the GPI 25way D type connector.
To start a macro associated with GPI In 1 On, make connection between pins
25 (GPI0) and 13 (GPI GND)
To start a macro associated with GPI In 1 Off, break connection between pins
25 (GPI0) and 13 (GPI GND)
For connector information refer to the diagram on page 150.
GPI Channels
GPI Signal name Type GPI Pin No
1 GPI1 IN/OUT
25
2 GPI2 IN/OUT
12
3 GPI3 IN/OUT
24
4 GPI4 IN/OUT
11
5 GPI5 IN/OUT
23
6 GPI6 IN/OUT
10
7 GPI7 IN/OUT
22
8 GPI8 IN 9
9 GPI9 IN 21
GND GND GND 13