C505_9708 SIEMENS [Siemens Semiconductor Group], C505_9708 Datasheet - Page 134

• Manufacturer Part Number: C505_9708
• Description: 8-Bit CMOS Microcontroller
• Manufacturer: SIEMENS [Siemens Semiconductor Group]

Mask Registers
Messages can use standard or extended identifiers. Incoming frames are masked with their
appropriate global masks. Bit IDE of the incoming message determines, if the standard 11-bit mask
in global mask short is to be used, or the 29-bit extended mask in global mask long. Bits holding a
“0” mean “don’t care”, ie. do not compare the message’s identifier in the respective bit position.
The last message object (15) has an additional individually programmable acceptance mask (mask
of last message) for the complete arbitration field. This allows classes of messages to be received
in this object by masking some bits of the identifier.
Note :The mask of last message is ANDed with the global mask that corresponds to the incoming
CAN Global Mask Short Register Low GMS0 (Address F706 H )
CAN Global Mask Short Register High GMS1 (Address F707 H )
Bit
ID28-18
Semiconductor Group
F706 H
F707 H
Bit No.
message.
MSB
7
Function
Identifier (11-bit)
Mask to filter incoming messages with standard identifier.
ID20-18
rw
6
5
1
4
r
ID28-21
6-72
rw
1
3
r
On-Chip Peripheral Components
1
2
r
Reset Value : UUU11111 B
1
1
r
Reset Value : UU H
1
0
r
C505C Only
LSB
1997-08-01
GMS1
GMS0