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Pelican vs basiccan addressing modes, Addressing examples – Connect Tech CANPRO CTIM-00043 User Manual

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CANpro/104 User Manual


CTIM-00043 (0.01) 1/15/2010

www.connecttech.com

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800-426-8979 | 519-836-1291

PeliCAN vs BasicCAN Addressing Modes

The SJA1000 can operate in 2 different modes, the PeliCAN mode which has extended features and
additional registers and which consume 128 bytes of address space per device (there are 2 devices on
this board). And, the BasicCAN mode which has reduced functionality but only consumes 32 bytes
of register space per device.

Note: The mode of operation of the SJA1000 is performed by changing Bit-7 of the Clock
Divider Register (which defaults to BasicCAN mode whenever a PC/104 Bus Reset occurs).

When the SJA1000’s are operated in BasicCAN mode, it is desirable to accommodate the smaller
number of registers by decoding a smaller amount of I/O Space (because the I/O Space region is
limited in total size).

The selection of Addressing Mode is done with Jumper J3C Position #2. This selection has no
meaning when Memory Space operation is enabled (see Jumper J3A above).

J3C Position #2

Function

Removed

PeliCAN Addressing mode enabled

Installed

BasicCAN Addressing mode enabled

Table 7

Addressing Examples

Example #1:

Memory Address 0x4A6000 (this address is above the 1-Meg boundary)
0x4A6000 =

0100.1010.011

X.XXXX.CJJJ.JJJJ (binary)

Address bits in

red

are matched against their respective Jumper settings.

X = Address bits that are ignored by the board.
C = Address bit that is used to select the SJA1000 controller.
J = Address bits that are used to select the SJA1000 registers.

Address

Bit

Bit

Value

J3A or J3B

Position

Installed

or Removed

23

0

J3A-2

Removed

22

1

J3A-3

Installed

21

0

Address Bit always decoded as “0”

20

0

Address Bit always decoded as “0”

19

1

J3A-4

Installed

18

0

J3A-5

Removed

17

1

J3A-6

Installed

16

0

J3B-1

Removed

15

0

J3B-2

Removed

14

1

J3B-3

Installed

13

1

J3B-4

Installed

Table 8