Infineon Technologies TC1796 - 22.5 Time-Triggered Extension (TTCAN Controller); 22.5.1 Generation of the Local Time

TC1796
Peripheral Units (Vol. 2 of 2)
Controller Area Network (MultiCAN) Controller
User’s Manual 22-114 V2.0, 2007-07
MultiCAN, V2.0
22.5 Time-Triggered Extension (TTCAN Controller)
22.5.1 Generation of the Local Time
The Nominal Time Unit (NTU) of the TTCAN controller is generated by the NTU timer
with a clock derived from the fractional divider (an NTU timer action takes place with t
q
or with a multiple of 1/f
CAN
). The sum of the NTU is the local time LT, which is a 16-bit
value (to be considered as integer number) and a fractional part LTFR.
Figure 22-25 Generation of the Local Time
MCA05851
LREFM
16
LREFMFR
REFM REFMFR
7
16
SYNM SYNMFR
7
16
LT LTFR
7
Reference
Message
Correctly
Transferred
Frame_Sync
(SOF)
16
16
10
10
Increment
by 1
Adder TUR
TURADJ
NTU Timer Control
New
Basic
Cycle
10
TTCAN Level
t
q
Nominal CAN
Bit Time
f
CAN
LTUR