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FUJITSU F2MCTM-16LX User Manual

Page 480

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464

CHAPTER 21 CAN CONTROLLER

The relationship between PSC = PSC5 to PSC0, TSI = TS1.3 to TS1.0, TS2 = TS2.2 to TS2.0, and RSJ =

RSJ1, RSJ0

RSJ1 and RSJ0 is shown below.

CLK: input clock (CLK)

TQ: time quanta

BT: bit time

SYNC_SEG: synchronous segment

TSEG1 and TSEG2: time segment 1 and 2

resynchronization jump width [(RSJ1 and RSJ0) +1] frequency division

For correct operation, the following conditions should be met.

In order to meet the bit timing requirements defined in the CAN specification, additions have to be met,

e.g. the propagation delay has to be considered.

TQ

= (PSC + 1) x CLK

BT

= SYNC_SEG + TSEG1 + TSEG2

= (1 + (TS1 + 1) + (TS2 +1)) x TQ

= (3 + TS1 +TS2) x TQ

RSJW = (RSJ + 1) x TQ

For 1 PSC 63:

TSEG1 2TQ

TSEG1 RSJW

TSEG2 2TQ

TSEG2 RSJW

For PSC = 0:

TSEG1 5TQ

TSEG2 2TQ

TSEG2 RSJW