CALIBRE
Issue 1.3 Page 3
22/07/99
CONNECTING THE ADAPTER TO YOUR SYSTEM
2.1. Connector Pinout
All external connections are made via a 9 way "D" socket:
Pin Normal Mode
10V
20V
30V
40V
5NC
6 SDA (Bi-directional)
7+5V
8 SCL (Bi-directional)
9NC
2.2. Bus Capacitance Limitations
The maximum allowable capacitance on the I2C bus in normal mode depends on the value of the SCL
and SDA master pull-ups, but never exceeds 400pF. Refer to Phillips Technical Handbook Book 4
Parts 12a and 12b for further details (see Further Information for references). Care should be tak en in
choosing a length and type of interconnecting cable which will not exceed this limit.
2.3. Power Supply
Pin 7 on the "D" connector is connected to the PICA93LV power supply. This supply is fitted with
overload protection and up to 0.250mA can be drawn from here.
When shipped to you the bus voltage was factory pre-set to 3.3V for use with low voltage memories.
You can adjust the voltage by inserting a small screwdriver through the hole in the front panel.
Your PICA93LV has been factory set for use on 3.3V I2C bus systems. Use on 5V I2C bus
systems without adjusting the voltage WILL CAUSE PERMANENT DAMAGE to the PICA93LV.
The fault is factory detectable and you WILL BE CHARGED FOR THE REPAIR.
2.4. Resetting the Adapter
Each time the PICA93LV is re-configured via the Setup function it is automatically reset by software.