ST72F561J4T6 STMicroelectronics, ST72F561J4T6 Datasheet - Page 187

• Manufacturer Part Number: ST72F561J4T6
• Description: IC MCU 8BIT 16K FLASH 44-LQFP
• Manufacturer: STMicroelectronics
• Series: ST7r

Specifications of ST72F561J4T6

• Core Processor: ST7
• Core Size: 8-Bit
• Speed: 8MHz
• Connectivity: CAN, LINSCI, SPI
• Peripherals: LVD, POR, PWM, WDT
• Number Of I /o: 32
• Program Memory Size: 16KB (16K x 8)
• Program Memory Type: FLASH
• Ram Size: 1K x 8
• Voltage - Supply (vcc/vdd): 3.8 V ~ 5.5 V
• Data Converters: A/D 16x10b
• Oscillator Type: External
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 44-LQFP
• Processor Series: ST72F5x
• Core: ST7
• Data Bus Width: 8 bit
• Data Ram Size: 1 KB
• Interface Type: CAN, SCI, SPI
• Maximum Clock Frequency: 8 MHz
• Number Of Programmable I/os: 48
• Number Of Timers: 3
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• Development Tools By Supplier: STX-RLINK
• Minimum Operating Temperature: - 40 C
• On-chip Adc: 10 bit, 16 Channel
• For Use With: 497-8374 - BOARD DEVELOPMENT FOR ST72F561
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -
• Lead Free Status / Rohs Status: Details

beCAN CONTROLLER (Cont’d)
10.9.7 BeCAN Cell Limitations
10.9.7.1 FIFO Corruption
FIFO corruption occurs in the following case:
WHEN the beCAN RX FIFO already holds two
messages (that is, FMP == 2)
WHILE the beCAN requests the transfer of a new
receive message into the FIFO (this lasts one CPU
cycle)
Figure 109. FIFO Corruption
and Receive Message D
Release Message C
Receive Message A
Receive Message B
Receive Message C
Release Message A
Release Message B
Receive Message E
Release Message E
Release Message B
AND the application releases the FIFO (with
the instruction CRFR = B_RFOM;)
THEN the internal FIFO pointer is not updat-
ed
BUT the FMP bits are updated correctly
* pointer to next receive location
v pointer to next message to be released
Initial State
FMP
0
1
2
3
2
2
3
2
1
0
v
E B C
v
v
v
A B C
E B C
E B C
* v
- - -
A - -
A B -
A B C
D B C
D B C
E B C
*
FIFO
*
*
v
* v
*
*
* v
v
*
*
*
v
v
When the FIFO is empty, v and * point to the same location
E released instead of B
* does not move because FIFO is full (normal operation)
D is overwritten by E
C released
* and v are not pointing to the same message
the FIFO is empty
* Does not move, pointer corruption
Normal operation
As the FIFO pointer is not updated correctly, this
causes the last message received to be overwrit-
ten by any incoming message. This means one
message is lost as shown in the example in
16. The beCAN will not recover normal operation
until a device reset occurs.
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Figure