
UM10800
All information provided in this document is subject to legal disclaimers.
© NXP Semiconductors N.V. 2016. All rights reserved.
User manual
Rev. 1.2 — 5 October 2016
379 of 487
NXP Semiconductors
UM10800
Chapter 25: LPC82x Flash In-System and In-Application Programming
25.6.1.14 ReadUID
25.6.1.15 Read CRC checksum <address> <no of bytes>
Get the CRC checksum of a block of RAM or flash. CMD_SUCCESS followed by 8 bytes
of CRC checksum in ASCII format.
The checksum is calculated as follows:
CRC-32 polynomial: x32 + x26 + x23 + x22 + x16 + x12 + x11 + x10 + x8 + x7 + x5 + x4 +
x2 + x + 1
Seed Value: 0xFFFF FFFF
No bit order reverse for data input
No 1’s complement for data input
No bit order reverse for CRC sum
No 1’s complement for CRC sum
Table 327. UART ISP ReadUID command
Command
N
Input
None
Return Code
CMD_SUCCESS followed by four 32-bit words of E-sort test information in ASCII
format. The word sent at the lowest address is sent first.
Description
This command is used to read the unique ID.
Table 328. UART ISP Read CRC checksum command
Command
S
Input
Address:
The data are read from this address for CRC checksum calculation. This
address must be on a word boundary.
Number of Bytes:
Number of bytes to be calculated for the CRC checksum; must
be a multiple of 4.
Return Code
CMD_SUCCESS followed by data in plain binary format
ADDR_ERROR (address not on word boundary) |
ADDR_NOT_MAPPED |
COUNT_ERROR (byte count is not a multiple of 4) |
PARAM_ERROR |
CODE_READ_PROTECTION_ENABLED
Description
This command is used to read the CRC checksum of a block of RAM or flash
memory. This command is blocked when code read protection is enabled.
Example
"S 268436736 4<CR><LF>" reads the CRC checksum for 4 bytes of data from
address 0x1000 0500.
If checksum value is 0xCBF43926, then the host will receive:
"3421780262 <CR><LF>"