lpcware

LPC1110FD20 Uart Bootloader (ISP Mode)

Discussion created by lpcware Employee on Jun 15, 2016
Latest reply on Jun 15, 2016 by lpcware
Content originally posted in LPCWare by folknology on Mon Apr 08 15:44:21 MST 2013

We have recently designed a board conaining a LPC1110FD20 among other things, during testing we figured we would try out using the ISP Bootloader over Uart as this enables the board firmware to be updated remotely via the afore mentioned uart. Unfortunately we have had zero sucess when testing with lpc2isp for example, even adjusting maxflashchunk sizes etc.. We tend to get bad CRC returns among other things (probably ram/stack corruptions). We always knew things would be tight on a device with only 1K Ram but recent test and calculations seem to indicate that what we are trying to do may actually be impossible, hence our complete failure to date, let me put it buy some more qualified folk such as yourselves.:


1) The bootloader (ISP Mode) uses low parts of the Ram itself (for ISP commands among others) as well as areas like the code read protection etc.. this means we can't use Ram below 0x10000300L basically the first 768 bytes!


2) The Bootloader flash commands use top 32 bytes and its stack adds up to 256 Bytes


<div>3) The minimum flash copy size chunk from Ram is 256 bytes</div>
<div>This all ads up to 768 + 32 + 256 + 256 = 1312 !</div>
<div>Oops, this appears to mean one cannot use the ISP bootloader over Uart with the LPC1110FD20</div>
<div>Is this correct? have we made a mistake? Please help, we seem to have wasted rather a lot of time finding this out the hard way...</div>
<div>regards</div>
<div>Al</div>

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