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Trouble writing STP1612PW05 config

temp2010
Senior
Posted on July 06, 2012 at 22:27

Please note that I'm not using an ST microprocessor or controller, but I am using the STP1612PW05.  I am having extreme difficulty finding support on this chip.  I can't find any more appropriate a forum than this one.  If you know of one, please let me know.  Regardless, your helpful advice for using this chip is greatly appreciated.

The funniest thing about the STP1612PW05 is that it *almost* uses an SPI interface, but not quite.  Instead of a normal chip select, it has an LE input that must be high for a specific amount of time during the SPI transfer.  The length of time LE is high determines what command is being executed and therefore what's done with the SPI data.

I have write data latch, write global latch, and read configuration commands working.  I'm unable to get the write configuration command working.  For example, I power up my target board and do a read configuration, write configuration, read configuration in order.  The first read configuration gives me 0x1EAC.  This is a number you can't get by accident, and it matches the default config register, so my read configuration must be working.  However, after I do the write configuration, all subsequent read configurations return all zeroes.  I've tried several variations of the write configuration, and I just can't get the read-back to work.

Meanwhile, the datasheet for the STP1612PW05 is abysmal at describing much of anything.

Please help!!!

Thanks

#nrnd
2 REPLIES 2
Posted on July 07, 2012 at 00:53

Support is not generally provided via forums, the process normally requires calling your ST representative and/or FAE.

The part also has a ''Do not use in new designs'' designation.

The data sheet describes the protocol in enough detail to code a bit-banged GPIO interface, or implement an FPGA. Yes, your right it's not a standard SPI interface, as you'd basically need to supply two bits at each clock. I've seen some bad data sheets in my time, this one doesn't look that bad. If it describes the function correctly it'll certainly rate better than average.

Without seeing some code it's hard to guess at why you're not succeeding.
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temp2010
Senior
Posted on July 08, 2012 at 21:33

Clive1, thanks for your response.

Please be aware that support is ALSO NOT provided by ST Microelectronics worth a flip.  I haven't gotten a response after a week and a half using their online support (email) system.

Regarding NRND, I sourced this part via Digikey and the datasheet, neither of which mention NRND.  I see that on the ST website now, however.  D*mn.

Bitbanging isn't required when using a Cypress PSoC, and anything related is NOT my problem here.  My problem is that the datasheet is probably wrong in detail.  Recall, I got three different commands confirmed working, two of them writes and one of them a config read.  So I should be ''close enough'' that the config write should work too, but it doesn't.

Given the NRND I might have to start over...