Cypress PSoC CY8C23533, Technical Reference Manual

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Document # 001-20559 Rev. *D 47
Supervisory ROM (SROM)
Address F8h is the return code byte for all SROM functions
(except Checksum and TableRead); for this function, the
only acceptable values are 00h and 02h. Address FCh is the
fail count variable. After POR (Power on Reset) or WDR, or
XRES (External Reset), the variable is initialized to 00h by
the SROM. Each time the checksum fails, the fail count is
incremented. Therefore, if it takes two passes through
SWBootReset to get a good checksum, the fail count would
be 01h.
3.1.2.2 ReadBlock Function
The ReadBlock function is used to read 64 contiguous bytes
from Flash: a
block . The number of blocks in a device is the
total number of bytes divided by 64. Refer to Table 3-5 to
determine the amount of space in your PSoC device.
The first thing the ReadBlock function does is check the pro-
tection bits to determine if the desired BLOCKID is readable.
If read protection is turned on, the ReadBlock function exits
setting the accumulator and KEY2 back to 00h. KEY1 has a
value of 01h, indicating a read failure.
If read protection is not enabled, the function reads 64 bytes
from the Flash using a ROMX instruction and stores the
results in SRAM using an MVI instruction. The 64 bytes are
stored in SRAM, beginning at the address indicated by the
value of the POINTER parameter. When the ReadBlock
completes successfully, the accumulator, KEY1, and KEY2
all have a value of 00h.
If the PSoC device has more than one bank of Flash, the
bank value in the FLS_PR1 register must be set prior to
executing the SSC instruction. Refer to
Table 3-5 .
Note MVI [expr], A is used to store the Flash block contents
in SRAM; thus, the MVW_PP register can be set to indicate
which SRAM pages receive the data.
Table 3-4. SRAM Map Post SWBootReset (00h)
Address
0 1 2 3 4 5 6 7
8 9 A B C D E F
0x0_
0x00 0x00 0x00 ?? ?? ?? ?? ??
?? ?? ?? ?? ?? ?? ?? ??
0x1_
?? ?? ?? ?? ?? ?? ?? ??
?? ?? ?? ?? ?? ?? ?? ??
0x2_
?? ?? ?? ?? ?? ?? ?? ??
?? ?? ?? ?? ?? ?? ?? ??
0x3_
?? ?? ?? ?? ?? ?? ?? ??
?? ?? ?? ?? ?? ?? ?? ??
0x4_
?? ?? ?? ?? ?? ?? ?? ??
?? ?? ?? ?? ?? ?? ?? ??
0x5_
?? ?? ?? ?? ?? ?? ?? ??
?? ?? ?? ?? ?? ?? ?? ??
0x6_
?? ?? ?? ?? ?? ?? ?? ??
?? ?? ?? ?? ?? ?? ?? ??
0x7_
?? ?? ?? ?? ?? ?? ?? ??
?? ?? ?? ?? ?? ?? ?? ??
0x8_
?? ?? ?? ?? ?? ?? ?? ??
?? ?? ?? ?? ?? ?? ?? ??
0x9_
?? ?? ?? ?? ?? ?? ?? ??
?? ?? ?? ?? ?? ?? ?? ??
0xA_
?? ?? ?? ?? ?? ?? ?? ??
?? ?? ?? ?? ?? ?? ?? ??
0xB_
?? ?? ?? ?? ?? ?? ?? ??
?? ?? ?? ?? ?? ?? ?? ??
0xC_
?? ?? ?? ?? ?? ?? ?? ??
?? ?? ?? ?? ?? ?? ?? ??
0xD_
?? ?? ?? ?? ?? ?? ?? ??
0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00
0xE_
0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00
0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00
0xF_
0x00 0x00 0x00 0x00 0x00 0x00 ?? ??
0x00
0x02
xx 0x00 0x00 0xn xx 0x00 0x00
Table 3-5. Flash Memory Organization
PSoC Device
Amount of
Flash
Amount of
SRAM
Number of
Blocks
per Bank
Number of
Banks
CY8C24633 8 KB 256 Bytes 128 2
CY8C23433 8 KB 256 Bytes 128 2
CY8C23533 8 KB 256 Bytes 128 2
CY8C24533 8 KB 256 Bytes 128 2
CY8C24x23A 4 KB 256 Bytes 64 1
Table 3-6. ReadBlock Parameters (01h)
Name Address Type Description
MVW_PP 0,D5h Register MVI write page pointer register.
KEY1 0,F8h RAM 3Ah.
KEY2 0,F9h RAM Stack Pointer value+3, when SSC is
executed.
BLOCKID 0,FAh RAM Flash block number.
POINTER 0,FBh RAM Addresses in SRAM where returned
data should be stored.
FLS_PR1 1,FAh Register Flash bank number.