Keil MCB167-NET, User Manual

Page: 11 / 31

MCB167-NET Board User’s Guide 11
Configuration Jumpers
The following sections describe each of the configuration jumpers of the
MCB167-NET board.
CAN1, CAN2: Default ON
The CAN1 and CAN2 configuration jumper enable on 120
Ω
termination resistor
on the CAN1 or CAN2 bus interface. This resistor is used on the end of each
CAN communication line.
P2.15: Default ON
The P2.15 configuration jumper provides the interrupt request signal of the
Ethernet controller to the EX7IN interrupt input of the C167 CPU.
EA/: Default ON
The EA/ configuration jumper selects on-chip or off-chip program execution.
With the default setting the CPU starts instruction execution from external
memory. When the EA/ jumper is off, code execution starts from on-chip ROM.
WRCFG: Default ON
The WRCFG configuration jumper selects the initial operation of the WR/ and
BHE/ signals. For correct operation the MCB167-NET board requires a WRH/
and WRL/ signal. Therefore this jumper should be always ON.
A20, A21, A22, A23: Default ON
The A20…A23 configuration jumpers connect the CAN bus drivers (IC9 and
IC11) to the C167 CAN interface signals. When you remove the A21 and A22
jumpers you disconnect the CAN1 bus driver. With A20 and A24 the CAN2 bus
driver is disconnected.