Just in case someone wants to know about read/write/erase AT49LVxxx:
To read ATMELS AT49LVxxx's reliably we *need* to choose the settings of 29LVXX even if in the latest 0.97ja there is a submenu for this specific device. Eg AT49LV1614 is in the Device menu on its own but all my readings were incorrect (every second byte was incorrect). Correct reading obtained only when we set the programmer to see the chip as 29LV160!
Also: In your ZIF TSOP48 adapter(with "GSM TOOL" lable on it). You need add a A21 address line so it reads 29LV320. But the jumper 28Vpp is basically uselles! Pin 12 is the RESET pin on a standard TSOP48. This pin should be connected really to this jumper upon request to apply or not high Vpp to the RESET pin. Instead in your TSOP48 ZIF, pin12 is connected constanly somewhere else where there is only a 4.x voltage.
You see some devices as the ATMELs AT49LVxxxx's, or the AM29DL323's they have what we call Secure Silicon sector (SecSi). And to succeed erasing this sector on the device (plus some other sectors), we need to apply in the RESET an unusal high Vpp (eg in AM29DL323 12-13Volts). This happens also in some ATMEL CPUs, (eg AVRs), they go to lock itselfs (loose ISP capabilities etc ) and then only a "parallel programming" (=high Vpp to RESET) make it possible to erase them.
Actually what you should had in your TSOP48 ZIF is a jumper betwwen the top two vertical pins , (by top I mean where "GSM TOOL" label is). One top pin is the the ending of the 28Vpp jumper when this jumper is ON and the other top pin is connected contantly to the pin12 (RESET) of TSOP48's.
Hence an extra jumper is needed (plus the extra A21 line), on the TSOP48 ZIF to perform the following function: When 28Vpp jumper is ON (i.e. we need high Vpp for RESET=pin12), this extra jumper should be OFF (disconnecting pin12 from where is connected right now constantly). And when 28Vpp jumper is OFF then pin12=RESET of TSOP48 must be connected exactly as in the current TSOP48 ZIF adapter to the other top pin, aka extra jumper sould be now ON!
With this arrangement (I cut the track coming form TSOP's pin12 and add an extra jumper), I was able to fully erase an AM29DL323 (as usual settings 29LV320), that had the security silicon sector on and also some other protected sectors. Plus it seems that such AM29LD323's with security silicon sector on need a constant 12V Vpp even when programmed (not only erased!). And this of course means that without the above Vpp modification for the pin12=RESET there is no way that you can program one AM29DL323 reliably using your current TSOP48 ZIF adaptrer (apart if the AM29DL323 is brand new and never written before).
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Read/write/Erase AT49LVxxx
Posted - 02/07/2005 : 11:43:10
