LPC Microcontrollers中的主题 Re: ISP programmer synchronization

ISP programmer synchronization

lpcware — Wed, 15 Jun 2016 19:50:05 GMT

Content originally posted in LPCWare by djonesboni on Tue Jan 13 22:23:21 MST 2015
Hello.

I am trying to program a LPC2366 via ISP (UART0).

When I send the '\x3F' (= '?') char for synchronization and the device don't send the synchronization string "Synchronized\x0D\x0A". Instead it sends back a '\x60' char.

<pre>tx=[ len=1 0x 3F ]
tx="?"
rx=[ len=1 0x 60 ]
rx="`"</pre>

I tried several baud rates.
50 bps up to 230400 bps I got the same ('`' '\x60').
Higher baud rates get other responses.
460800 up to 1152000 I get 'p' '\x70'.
1500000 up to 2500000 I get 'x' '\x78'.
3000000 up to 4000000 I get '\xFC'.

Resending several times the synchronization char does the same.
The device is started with LOW level on P2.10.

What may be wrong?

Best regards.

Re: ISP programmer synchronization

lpcware — Wed, 15 Jun 2016 19:50:06 GMT

Content originally posted in LPCWare by capiman on Tue Jan 13 22:49:37 MST 2015
Can you try lpc21isp? Or if you have a supported OS, perhaps FlashMagic?

Re: ISP programmer synchronization

lpcware — Wed, 15 Jun 2016 19:50:07 GMT

Content originally posted in LPCWare by djonesboni on Wed Jan 14 06:02:59 MST 2015

Quote: capiman
Can you try lpc21isp? Or if you have a supported OS, perhaps FlashMagic?

Thanks very much :)
lpc21isp fits my needs. It will save me a lot of work.

But it also do not work yet, it gets stuck on synchronization.

I think the problem may be with the serial bus itself.
We use a rs485 bus and sp485 transceivers, which need set DE and RE to transmit and clear them to receive.
The ISP bootloader is not aware of that, so it cannot transmit or receive (at least not both).

Would a rs232 bus (with max232 transceivers) be fine for programming?

I need to find out what are these bytes that I'm receiving (they only appear when the board has power).
Any clue?

Re: ISP programmer synchronization

lpcware — Wed, 15 Jun 2016 19:50:07 GMT

Content originally posted in LPCWare by R2D2 on Wed Jan 14 06:19:50 MST 2015

Quote: djonesboni
Would a rs232 bus (with max232 transceivers) be fine for programming?

ISP isn't very fast :D

So using a MAX2322 (UART <-> RS232) or FTDI (UART <-> USB) should work without problems :)

Re: ISP programmer synchronization

lpcware — Wed, 15 Jun 2016 19:50:08 GMT

Content originally posted in LPCWare by djonesboni on Wed Jan 21 08:06:58 MST 2015
In my case fast/slow doesn't matter.
But it must be cheap :)

Re: ISP programmer synchronization

lpcware — Wed, 15 Jun 2016 19:50:09 GMT

Content originally posted in LPCWare by starblue on Wed Jan 21 08:27:56 MST 2015
The simplest and cheapest is probably to use a USB to serial converter with 3.3V logic levels, and just a connector on the board.