Bluetooth® Tally System
Fig 7.
To find out how Philips work we got an original philips viewfinder
and started to listen on the circuits.
It turns out that the Philips camera needs to know what kind of viewfinder that
is placed on the camera.
This information is stored in a small EEPROM chip. We copied all the information
on the memory to one of our own to
fool the camera to think that we had a viewfinder placed on the camera. This
EEPROM (73-970-29) chip and another
chip is a I2C-bus (73-855-11).
The image is the setup we came up with. The I2C bus, the memory and a relay,
a quite big relay in comparision
with the other components but it is very sensitive and works between 9V-15V
(37-115-46).
Product numbers can be used on www.elfa.se