Nxp Semiconductors UM10237 ユーザーズマニュアル

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UM10237_2
© NXP B.V. 2008. All rights reserved.
User manual
Rev. 02 — 19 December 2008 
685 of 792
NXP Semiconductors
UM10237
Chapter 30: LPC24XX Flash memory programming firmware
9.3 Echo <setting>
 
9.4 Write to RAM <start address> <number of bytes>
The host should send the data only after receiving the CMD_SUCCESS return code. The 
host should send the check-sum after transmitting 20 UU-encoded lines. The checksum is 
generated by adding raw data (before UU-encoding) bytes and is reset after transmitting 
20 UU-encoded lines. The length of any UU-encoded line should not exceed 
61 characters(bytes) i.e. it can hold 45 data bytes. When the data fits in less then 
20 UU-encoded lines then the check-sum should be of the actual number of bytes sent. 
The ISP command handler compares it with the check-sum of the received bytes. If the 
check-sum matches, the ISP command handler responds with "OK<CR><LF>" to 
continue further transmission. If the check-sum does not match, the ISP command 
handler responds with "RESEND<CR><LF>". In response the host should retransmit the 
bytes.
 
9.5 Read Memory <address> <no. of bytes>
The data stream is followed by the command success return code. The check-sum is sent 
after transmitting 20 UU-encoded lines. The checksum is generated by adding raw data 
(before UU-encoding) bytes and is reset after transmitting 20 UU-encoded lines. The 
length of any UU-encoded line should not exceed 61 characters(bytes) i.e. it can hold 
45 data bytes. When the data fits in less then 20 UU-encoded lines then the check-sum is 
of actual number of bytes sent. The host should compare it with the checksum of the 
received bytes. If the check-sum matches then the host should respond with 
Table 608. ISP Echo command
Command
A
Input
Setting: ON = 1 | OFF = 0
Return Code
CMD_SUCCESS |
PARAM_ERROR
Description
The default setting for echo command is ON. When ON the ISP command handler 
sends the received serial data back to the host.
Example
"A 0<CR><LF>" turns echo off.
Table 609. ISP Write to RAM command
Command
W
Input
Start Address:
 RAM address where data bytes are to be written. This address 
should be a word boundary.
Number of Bytes:
 Number of bytes to be written. Count should be a multiple of 4
Return Code
CMD_SUCCESS |
ADDR_ERROR (Address not on word boundary) |
ADDR_NOT_MAPPED |
COUNT_ERROR (Byte count is not multiple of 4) |
PARAM_ERROR |
CODE_READ_PROTECTION_ENABLED
Description
This command is used to download data to RAM. Data should be in UU-encoded 
format. This command is blocked when code read protection is enabled.
Example
"W 1073742336 4<CR><LF>" writes 4 bytes of data to address 0x4000 0200.