Fetch ACK
No
Yes
End
No
Process NAK
Yes
Report an error
No
Yes
No
Reached
maximum
retries?
Report a timeout
error
Yes
0x5A
received?
0xA2
received?
0xA1
received?
Read 1 byte
from target
Read 1 byte
from target
Figure 13-19. Host reads ACK packet from target via I2C
Fetch
Response
Yes
Yes
payload length
part from target
(2 bytes)
CRC checksum
from target
Payload length
less than supported
length?
Yes
payload data
from target
No
Set payload length
to maximum
supported length
No
No
Reached
maximum
Report a timeout
Yes
End
No
(2 bytes)
Read 1 byte
from target
0x5A
received?
0xA4
received?
Read 1 byte
from target
retries?
error (End)
Read
Read
Read
Figure 13-20. Host reads response from target via I2C
13.4.2
SPI Peripheral
The Kinetis Flashloader supports loading data into flash via the SPI peripheral, where the
SPI peripheral serves as a SPI slave.
Chapter 13 Kinetis Flashloader
K22F Sub-Family Reference Manual, Rev. 4, 08/2016
NXP Semiconductors 329