CYRF69213 Datasheet, PDF (18/85 Pages) Cypress Semiconductor – Programmable Radio on Chip Low Power

CYRF69213
and DELAY values must be set correctly. The CLOCK value
determines the length of the write pulse that will be used to
store the data in the Flash. The CLOCK and DELAY values are
dependent on the CPU speed. Refer to ‘Clocking’ Section for
additional information.
Table 24.WriteBlock Parameters
Name Address
Description
KEY1
0,F8h 3Ah
KEY2
0,F9h
Stack Pointer value, when SSC is
executed
BLOCKID 0,FAh
8-KB Flash block number (00h–7Fh)
4-KB Flash block number (00h–3Fh)
3-KB Flash block number (00h–2Fh)
POINTER 0,FBh
First of 64 addresses in SRAM, where
the data to be stored in Flash is located
prior to calling WriteBlock
CLOCK 0,FCh
Clock divider used to set the write
pulse width
DELAY 0,FEh For a CPU speed of 12 MHz set to 56h
EraseBlock Function
The EraseBlock function is used to erase a block of 64
contiguous bytes in Flash. The first thing the EraseBlock
function does is to check the protection bits and determine if
the desired BLOCKID is writable. If write protection is turned
on, the EraseBlock function will exit, setting the accumulator
and KEY2 back to 00h. KEY1 will have a value of 01h,
indicating a write failure. The EraseBlock function is only
useful as the first step in programming. Erasing a block will not
cause data in a block to be one hundred percent unreadable.
If the objective is to obliterate data in a block, the best method
is to perform an EraseBlock followed by a WriteBlock of all
zeros.
To set up the parameter block for the EraseBlock function,
correct key values must be stored in KEY1 and KEY2. The
block number to be erased must be stored in the BLOCKID
variable and the CLOCK and DELAY values must be set based
on the current CPU speed.
Table 25.EraseBlock Parameters
Name
KEY1
KEY2
Address
Description
0,F8h 3Ah
0,F9h
Stack Pointer value when SSC is
executed
BLOCKID 0,FAh
CLOCK 0,FCh
DELAY 0,FEh
Flash block number (00h–7Fh)
Clock divider used to set the erase
pulse width
For a CPU speed of 12 MHz set to 56h
ProtectBlock Function
The CYRF69213 device offers Flash protection on a
block-by-block basis. Table 26 lists the protection modes
available. In the table, ER and EW are used to indicate the
ability to perform external reads and writes. For internal writes,
IW is used. Internal reading is always permitted by way of the
ROMX instruction. The ability to read by way of the SROM
ReadBlock function is indicated by SR. The protection level is
stored in two bits according to Table 26. These bits are bit
packed into the 64 bytes of the protection block. Therefore,
each protection block byte stores the protection level for four
Flash blocks. The bits are packed into a byte, with the lowest
numbered block’s protection level stored in the lowest
numbered bits.
The first address of the protection block contains the
protection level for blocks 0 through 3; the second address is
for blocks 4 through 7. The 64th byte will store the protection
level for blocks 252 through 255.
Table 26.Protection Modes
Mode Settings
Description
Marketing
00b SR ER EW IW Unprotected Unprotected
01b SR ER EW IW Read protect Factory upgrade
10b SR ER EW IW Disable external Field upgrade
write
11b SR ER EW IW Disable internal Full protection
write
7
6
Block n+3
5
4
Block n+2
3
2
Block n+1
1
0
Block n
The level of protection is only decreased by an EraseAll, which
places zeros in all locations of the protection block. To set the
level of protection, the ProtectBlock function is used. This
function takes data from SRAM, starting at address 80h, and
ORs it with the current values in the protection block. The
result of the OR operation is then stored in the protection
block. The EraseBlock function does not change the
protection level for a block. Because the SRAM location for the
protection data is fixed and there is only one protection block
per Flash macro, the ProtectBlock function expects very few
variables in the parameter block to be set prior to calling the
function. The parameter block values that must be set, besides
the keys, are the CLOCK and DELAY values.
Table 27.ProtectBlock Parameters
Name
KEY1
KEY2
CLOCK
DELAY
Address
Description
0,F8h 3Ah
0,F9h
Stack Pointer value when SSC is
executed
0,FCh
Clock divider used to set the write
pulse width
0,FEh For a CPU speed of 12 MHz set to 56h
EraseAll Function
The EraseAll function performs a series of steps that destroy
the user data in the Flash macros and resets the protection
block in each Flash macro to all zeros (the unprotected state).
The EraseAll function does not affect the three hidden blocks
above the protection block in each Flash macro. The first of
Document #: 001-07552 Rev. *B
Page 18 of 85
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