NXP Semiconductors LPC43Sxx, Руководство пользователя

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User manual Rev. 2.1 — 10 December 2015 88 of 1441
NXP Semiconductors
UM10503
Chapter 6: LPC43xx/LPC43Sxx flash programming/ISP and IAP
4. Set the function pointer:
IAP iap_entry=(IAP)IAP_LOCATION;
5. Use the following statement to call the IAP:
iap_entry (command_param,status_result);
The IAP call can be simplified further by using the symbol definition file feature supported
by ARM Linker in RVDS (Realview Development Suite). You can also call the IAP routine
using assembly code. According to the ARM architecture Procedure Calling Standard
(AAPCS), up to 4 parameters can be passed in the r0, r1, r2 and r3 registers respectively.
Additional parameters are passed on the stack. Up to 4 parameters can be returned in the
r0, r1, r2 and r3 registers respectively. Additional parameters are returned indirectly via
memory. Some of the IAP calls require more than 4 parameters. If the ARM suggested
scheme is used for the parameter passing/returning then it might create problems due to
difference in the C compiler implementation from different vendors. The suggested
parameter passing scheme reduces this risk.
The flash memory is not accessible during a write or an erase operation. IAP commands
which result in a flash write/erase operation use 32 bytes of space in the top portion of the
on-chip RAM for execution. The user program should not be using this space if IAP flash
programming is permitted in the application. Maximum stack usage is mentioned in the
description of a command.
6.8.1 IAP Initialization
This command initializes and prepares the flash for erase and write operations.
Table 51. IAP Command Summary
IAP Command Command Code Reference
Init 49
10
Table 52
Prepare sectors for write operation 50
10
Table 53
Copy RAM to Flash 51
10
Table 54
Erase sectors 52
10
Table 55
Blank check sectors 53
10
Table 56
Read part ID 54
10
Table 57
Read Boot Code version 55
10
Table 58
Read device serial number 58
10
Table 59
Compare 56
10
Table 60
Reinvoke ISP 57
10
Table 61
Erase page 59
10
Table 62
Set active boot flash bank 60
10
Table 63
Table 52. IAP Initialization command
Command Init IAP
Input Command code: 49 (decimal)
Status Code CMD_SUCCESS