NXP Semiconductors LPC24XX UM10237 - Manual (Page 684)

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User manual Rev. 04 — 26 August 2009 684 of 792
NXP Semiconductors
UM10237
Chapter 30: LPC24XX Flash memory programming firmware
9.1 Unlock
9.2 Set Baud Rate
[1] ISP entry after reset uses the on chip IRC and PLL to run the device at CCLK = 14.748 MHz
Read Part ID J Table 30–615
Read Boot code version K Table 30–617
Compare M Table 30–618
Table 603. ISP command summary
ISP Command Usage Described in
Table 604. ISP Unlock command
Command U
Input Unlock code: 23130
10
Return Code CMD_SUCCESS |
INVALID_CODE |
PARAM_ERROR
Description This command is used to unlock Flash Write, Erase, and Go commands.
Example "U 23130" unlocks the Flash Write/Erase & Go commands.
Table 605. ISP Set Baud Rate command
Command B
Input Baud Rate: 9600 | 19200 | 38400 | 57600 | 115200 | 230400
Stop bit: 1 | 2
Return Code CMD_SUCCESS |
INVALID_BAUD_RATE |
INVALID_STOP_BIT |
PARAM_ERROR
Description This command is used to change the baud rate. The new baud rate is effective
after the command handler sends the CMD_SUCCESS return code.
Example "B 57600 1" sets the serial port to baud rate 57600 bps and 1 stop bit.
Table 606. Correlation between possible ISP baudrates and CCLK frequency (in MHz)
ISP Baudrate .vs.
CCLK Frequency 9600 19200 38400 57600 115200 230400
10.0000 + + +
11.0592 + + +
12.2880 + + +
14.7456 [1] + + + + + +
15.3600 +
18.4320 + + +
19.6608 + + +
24.5760 + + +
25.0000 + + +