ST72521 STMICROELECTRONICS [STMicroelectronics], ST72521 Datasheet - Page 140

• Manufacturer Part Number: ST72521
• Description: 8-BIT MCU WITH NESTED INTERRUPTS, FLASH, 10-BIT ADC, FIVE TIMERS, SPI, SCI, I2C, CAN INTERFACE
• Manufacturer: STMICROELECTRONICS [STMicroelectronics]

ST72521
CONTROLLER AREA NETWORK (Cont’d)
FILTER HIGH REGISTERS (FHRx)
Read/Write
Reset Value: Undefined
FIL[11:3] are the most significant 8 bits of a 12-bit
message filter. The acceptance filter is compared
bit by bit with the identifier and the RTR bit of the
incoming message. If there is a match for the set
of bits specified by the acceptance mask then the
message is stored in a receive buffer.
FILTER LOW REGISTERS (FLRx)
Read/Write
Reset Value: Undefined
FIL[3:0] are the least significant 4 bits of a 12-bit
message filter.
140/211
FIL11
FIL3
7
7
FIL10
FIL2
FIL9
FIL1
FIL8
FIL0
FIL7
0
FIL6
0
FIL5
0
FlL4
0
0
0
MASK HIGH REGISTERS (MHRx)
Read/Write
Reset Value: Undefined
MSK[11:3] are the most significant 8 bits of a 12-
bit message mask. The acceptance mask defines
which bits of the acceptance filter should match
the identifier and the RTR bit of the incoming mes-
sage.
MSK
MSK
MASK LOW REGISTERS (MLRx)
Read/Write
Reset Value: Undefined
MSK[3:0] are the least significant 4 bits of a 12-bit
message mask.
MSK1
MSK3 MSK2 MSK1 MSK0
7
1
7
i
i
= 0: don’t care.
= 1: match required.
MSK1
0
MSK9 MSK8 MSK7 MSK6 MSK5 MSK4
0
0
0
0
0
0