ST52F513G3M6 STMicroelectronics, ST52F513G3M6 Datasheet - Page 39

• Manufacturer Part Number: ST52F513G3M6
• Manufacturer: STMicroelectronics

Specifications of ST52F513G3M6

• Cpu Family: ST52
• Device Core Size: 8b
• Frequency (max): 20MHz
• Interface Type: I2C/SCI/SPI
• Program Memory Type: Flash
• Program Memory Size: 8KB
• Total Internal Ram Size: 256Byte
• # I/os (max): 22
• Number Of Timers - General Purpose: 2
• Operating Supply Voltage (typ): 3.3/5V
• Operating Supply Voltage (max): 5.5V
• Operating Supply Voltage (min): 2.7V
• On-chip Adc: 8-chx10-bit
• Instruction Set Architecture: CISC
• Operating Temp Range: -40C to 85C
• Operating Temperature Classification: Industrial
• Mounting: Surface Mount
• Pin Count: 28
• Package Type: SO
• Lead Free Status / Rohs Status: Compliant

Figure 4.5 Error Handling Procedure
When the device is locked, if memory reading is
attempted, with the exception of the Lock Byte and
ID Code block, the device returns no data and an
error sequence. If memory writing is attempted in
any memory location, the device doesn’t carry out
the command and returns an error sequence.
To unlock the device the GlobalErase command
must be executed before any writing or reading
command.
4.5 ID Code
Block 3 on Page 48 (030h) can also be read if the
device is locked. The first byte of the block is the
Lock Byte, the following 21 locations (bytes 1-21)
are available to the user for writing data, as for
example identification codes to distinguish the
firmware version loaded in the device.
Warning: do not perform writing on the last 8 bytes
(bytes 22 to 31), because they are reserved.
The ID Code must be written before locking the
device: after the device is locked it can only be
read. The blocks 0, 1 and 2 on Page 48 can be also
be used for writing data, but they cannot be
accessed when the device is locked.
Note: the ID Code cannot be modified if the device
is locked: it can only be read.
Table 4.3 Error codes
Wrong command/data case handling:
S=Start, P=Stop, A=Acknowledge, NA=Non-acknowledge
Device Locked
Wrong Command
Not Allowed
Wrong Mode
Wrong Command/Data A
..... 10100001
From Slave to Master
Name
A
x0000101
x0010000
Status Byte NA P
x0000110
xyyyyyyy
Code
Command/Data NA P S 10100000
x=lock bit (1=device locked), yyyyyyy=error code
The Master sent a wrong command code
A command not allowed when the device is locked has been sent
A code different form the Programming mode code (00000000) has been sent
From Master to Slave
4.6 Error cases
If a wrong command or data is sent to the device,
it generates an error condition by not sending the
acknowledge after the first successive data or
command.
The error case can be handled by using the
ReadStatus command. This command can be sent
after the error condition is detected; the device
returns a Status Byte containing the error code.
The ReadStatus command sequence is showed in
Figure
in
Remark:
execution or after any error, the Start Sequence
must be carried out before sending a new
command.
The Most Significative Bit of the error codes
indicates (when set to ‘1’) that the memory is
locked. When a command, that is not allowed
when the memory is locked, is sent, the “Not
Allowed” code is sent. If another code is sent with
the MSB to ‘1’ it indicates that the error condition is
not caused by the memory lock, but by the event
related with the code sent.
Warning: when the data writing into a non existing
location is attempted, no error condition is
generated. The user must take care in specifying
the correct page address.
Table
4.5. The list of the error codes is illustrated
4.3.
Description
Figure 4.5
A
after
ReadStatus A P S .....
the
shows the error sequence.
ST52510xx ST52513xx
ReadStatus
command
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