Rainbow Electronics DS1216 - Manual (Page 6)

DS1216
6 of 13
RESET AND MEMORY DENSITY OPTIONS Figure 2
The letter suffix of the SmartWatch is located on the PCB as shown above.
The RESET pin on the controller has an internal pullup resistor. To disable the RESET function, the trace
between pin 1 on the socket and pin 13 on the controller can be cut. In this case, the socket will ignore the
RESET input, preventing address transitions from resetting the pattern match, even if the RST bit is
enabled.
On the DS1216B and DS1216D, the two V
CC
pins are connected together on the PCB. The switched V
CC
from the controller is connected to the two V
CC
pins that connect to the inserted RAM. No modifications
are required if the lower density RAM is used. To use the higher density RAM, the trace by the lower
density RAM V
CC
pin, identified by a hash mark labeled “U,” must be cut. The two square-metal pads,
labeled “G,” must be shorted together. This disconnects switched V
CC
from the pin going to the inserted
RAM, and connects it to the corresponding address input pin for the higher density RAM.