REX:flash: Difference between revisions
(15 intermediate revisions by the same user not shown) | |||
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You may have to search ebay or other suppliers for these parts. | You may have to search ebay or other suppliers for these parts. | ||
The specs you need | The specs you need are: | ||
:parallel flash memory | :parallel flash memory | ||
:5 volt | :5 volt | ||
Line 22: | Line 22: | ||
To search for a compatible flash chip, follow this: | To search for a compatible flash chip, follow this: | ||
1 | '''1)''' Start by searching for "29F800" on any supplier site like DigiKey, Mouser, ebay, Verical, etc, or just google. | ||
: | :All the parts turned up from that search should be: | ||
:: flash memory | :: flash memory | ||
:: single power supply | :: single power supply | ||
Line 31: | Line 30: | ||
:: boot sector / boot block | :: boot sector / boot block | ||
There is no consistent way to search or | :There is no consistent way to search for, or eliminate, the remaining specs by part number, because each manufacturer specifies these properties differently in their part numbers. | ||
:For each potential part... | |||
'''2)''' Search for the datasheet for that part number. Find the legend that shows how to decipher the part number. Usually it's towards the end of the document. Using the part number legend... | |||
'''3)''' Verify the part is a TSOP48 package, standard pinout. (If there is no separate "reversed pinout" option, then the pinout is standard.) | |||
'''4)''' Verify the boot block is "bottom boot". | |||
'''5)''' Any speed 90ns or faster is ok, but the slower the better. (Old computers are crude and have a lot of noise on the bus, and fast parts can be fast enough to misinterpret some noise as data, while the noise is too high frequency to register as a valid pulse for a slower part. So slower is actually better than faster in this case.) | |||
'''6)''' Any temperature range is fine. It doesn't hurt to get the more expensive industrial, automotive, or military temperature ranges, but the cheaper more common commercial range is fine. | |||
'''7)''' Other possible options like burn-in, packaging, rohs, etc you can ignore. | |||
==Some examples of compatible parts== | ==Some examples of compatible parts== | ||
Line 52: | Line 51: | ||
<pre> | <pre> | ||
Alliance | |||
AS29CF800B-**T** | |||
AS29CF800B-55TIN | |||
Macronix | Macronix | ||
MX29F800*BT*-*** | MX29F800*BT*-*** | ||
MX29F800CBTI-70G | MX29F800CBTI-70G | ||
MX29F800BTC-70 | MX29F800BTC-70 | ||
Micron / Alliance (Originally a Micron part, discontinued, now Alliance makes a clone.) | |||
M29F800FB**N** | |||
M29F800FB5AN6E2 | |||
AMD | AMD | ||
Line 82: | Line 89: | ||
==Part number legends for a few manufacturers== | ==Part number legends for a few manufacturers== | ||
<pre> | <pre> | ||
Alliance | |||
AS 29CF 800 B - 55 T I N | |||
| | | | | | +- rohs | |||
| | | | | +- temperature | |||
| | | | +- tsop | |||
| | | +- speed | |||
| | +- bottom boot | |||
| +- 8M | |||
| | |||
+- parallel flash, 5v | |||
-------------------------------------------------------------------------- | -------------------------------------------------------------------------- | ||
Line 88: | Line 105: | ||
AM 29F 800B B - 70 E K | AM 29F 800B B - 70 E K | ||
| | | | | +- temperature | | | | | | +- temperature | ||
| | | | +- | | | | | +- tsop | ||
| | | +- speed | | | | +- speed | ||
| | +- bottom boot | | | +- bottom boot | ||
| +- 8M | | +- 8M, boot block | ||
+- flash, 5v | +- parallel flash, 5v | ||
-------------------------------------------------------------------------- | -------------------------------------------------------------------------- | ||
Line 98: | Line 115: | ||
Macronix | Macronix | ||
MX | MX 29F 800 C B T I - 70 G | ||
| | | | | | | | | +- rohs | ||
| | | | | | | | +- speed | ||
| | | | | | | +- temperature | ||
| | | | | | +- tsop | ||
| | | | | +- bottom boot | ||
| | | | +- revision | ||
| | | +- 8M | ||
+- parallel flash, 5v | |||
+- flash, | |||
-------------------------------------------------------------------------- | -------------------------------------------------------------------------- | ||
Line 126: | Line 142: | ||
Fuji | Fuji | ||
MBM | MBM 29F 800 B A - 70 PFTN | ||
| | | | | +- PFTN = tsop48, standard pinout | |||
| | | | +- speed | |||
| | | +- revision | |||
| | +- bottom boot | |||
| +- 8M | |||
+- parallel flash, 5v | |||
-------------------------------------------------------------------------- | -------------------------------------------------------------------------- | ||
Line 137: | Line 157: | ||
| | | | | | | | +- speed | | | | | | | | | +- speed | ||
| | | | | | | +- tsop | | | | | | | | +- tsop | ||
| | | | | | +- bottom boot | | | | | | | +- bottom boot | ||
| | | | | +- temperature | | | | | | +- temperature | ||
| | | | +- | | | | | +- 5v | ||
| | | +- | | | | +- revision | ||
| | +- | | | +- 8M | ||
| +- | | +- parallel flash | ||
+- status M: motorola qualified | +- status M: motorola qualified | ||
</pre> | </pre> | ||
==example links== | |||
*[https://www.digikey.com/short/9339z5hp Macronix MX29F800CBTI-70G from DigiKey] | |||
*[https://www.digikey.com/short/p7mrtt41 Alliance M29F800FB5AN6E2 from DigiKey] | |||
*[https://mou.sr/3VUlRcy Alliance M29F800FB5AN6F2 from Mouser] | |||
*[ | *[https://mou.sr/3iN7Iji Alliance AS29CF800B-55TIN from Mouser] | ||
*[https://www.verical.com/s/am29f800bb/ AM29F800BB from Verical] | *[https://www.verical.com/s/am29f800bb/ AMD AM29F800BB from Verical] | ||
:Pick any version of the chip which matches this pattern: | :Pick any version of the chip which matches this pattern: | ||
::AM29F800BB-##E* | ::AM29F800BB-##E* | ||
Line 162: | Line 186: | ||
:Examples: | :Examples: | ||
:AM29F800BB-70EK | :AM29F800BB-70EK | ||
:[https://www.verical.com/pd/cypress-semiconductor-parallel-nor-flash-am29f800bb-90ef%28spansion%29-5050603 AM29F800BB-90EF] (except, that particular entry has a minimum order quantity of 98, at $6 per chip. So you can't use this link to buy 3 chips, but it shows how to identify a correct part. The datasheet for AM29F800BB shows that the 2nd B in " | :[https://www.verical.com/pd/cypress-semiconductor-parallel-nor-flash-am29f800bb-90ef%28spansion%29-5050603 AM29F800BB-90EF] (except, that particular entry has a minimum order quantity of 98, at $6 per chip. So you can't use this link to buy 3 chips, but it shows how to identify a correct part. Otherwise this part matches because: The datasheet for AM29F800BB shows that the 2nd "B" in "29F800BB" means bottom boot, and the "E" in "-90EF" means TSOP48) |
Latest revision as of 08:52, 7 December 2022
Compatible flash chip for REX
The flash chip in the pre-loaded DigiKey cart may be out of stock because it is becoming obsolete.
The exact part in the cart is just one of several equivalent compatible parts that could be used in it's place.
There are several properties that you have to verify in order to find another part that is compatible.
You may have to search ebay or other suppliers for these parts.
The specs you need are:
- parallel flash memory
- 5 volt
- single power supply / single voltage (same 5v used for reading and programming)
- 8 Mbit (1Mx8/512Kx16)
- boot sector
- bottom boot
- TSOP48
- 90ns or faster
The generic part number series is "29F800", with different extra characters added depending on manufacturer.
To search for a compatible flash chip, follow this:
1) Start by searching for "29F800" on any supplier site like DigiKey, Mouser, ebay, Verical, etc, or just google.
- All the parts turned up from that search should be:
- flash memory
- single power supply
- 5v
- 8Mbit x8/x16
- boot sector / boot block
- There is no consistent way to search for, or eliminate, the remaining specs by part number, because each manufacturer specifies these properties differently in their part numbers.
- For each potential part...
2) Search for the datasheet for that part number. Find the legend that shows how to decipher the part number. Usually it's towards the end of the document. Using the part number legend...
3) Verify the part is a TSOP48 package, standard pinout. (If there is no separate "reversed pinout" option, then the pinout is standard.)
4) Verify the boot block is "bottom boot".
5) Any speed 90ns or faster is ok, but the slower the better. (Old computers are crude and have a lot of noise on the bus, and fast parts can be fast enough to misinterpret some noise as data, while the noise is too high frequency to register as a valid pulse for a slower part. So slower is actually better than faster in this case.)
6) Any temperature range is fine. It doesn't hurt to get the more expensive industrial, automotive, or military temperature ranges, but the cheaper more common commercial range is fine.
7) Other possible options like burn-in, packaging, rohs, etc you can ignore.
Some examples of compatible parts
Examples:
Alliance AS29CF800B-**T** AS29CF800B-55TIN Macronix MX29F800*BT*-*** MX29F800CBTI-70G MX29F800BTC-70 Micron / Alliance (Originally a Micron part, discontinued, now Alliance makes a clone.) M29F800FB**N** M29F800FB5AN6E2 AMD AM29F800BB-##E* AM29F800BB-70EC AM29F800BB-70EI AM29F800BB-70EK AM29F800BB-90EF AM29F800BB-55EC STMicroelectronics M29F800*B##N# M29F800AB90N1 M29F800DB70N6 Fuji MBM29F800BA-##PFTN MBM29F800BA-70PFTN Motorola *29F800*5*BT## M29F800A5KBT80
Part number legends for a few manufacturers
Alliance AS 29CF 800 B - 55 T I N | | | | | | +- rohs | | | | | +- temperature | | | | +- tsop | | | +- speed | | +- bottom boot | +- 8M | +- parallel flash, 5v -------------------------------------------------------------------------- AMD AM 29F 800B B - 70 E K | | | | | +- temperature | | | | +- tsop | | | +- speed | | +- bottom boot | +- 8M, boot block +- parallel flash, 5v -------------------------------------------------------------------------- Macronix MX 29F 800 C B T I - 70 G | | | | | | | +- rohs | | | | | | +- speed | | | | | +- temperature | | | | +- tsop | | | +- bottom boot | | +- revision | +- 8M +- parallel flash, 5v -------------------------------------------------------------------------- STMicroelectronics M 29 F 800D B 55 N 6 | | | | | | +- temperature | | | | | +- tsop | | | | +- speed | | | +- bottom boot | | +- 800A, 800D: 8M, x8/x16, Boot Block | +- 5v +- flash -------------------------------------------------------------------------- Fuji MBM 29F 800 B A - 70 PFTN | | | | | +- PFTN = tsop48, standard pinout | | | | +- speed | | | +- revision | | +- bottom boot | +- 8M +- parallel flash, 5v -------------------------------------------------------------------------- Motorola M 29F 800 A 5 K B T 80 | | | | | | | | +- speed | | | | | | | +- tsop | | | | | | +- bottom boot | | | | | +- temperature | | | | +- 5v | | | +- revision | | +- 8M | +- parallel flash +- status M: motorola qualified
example links
- Pick any version of the chip which matches this pattern:
- AM29F800BB-##E*
- Where:
- ## = Speed: 90 or faster (90 or less)
- E = Package: Must be "E", which is TSOP
- * = Temperature range code: Any
- Examples:
- AM29F800BB-70EK
- AM29F800BB-90EF (except, that particular entry has a minimum order quantity of 98, at $6 per chip. So you can't use this link to buy 3 chips, but it shows how to identify a correct part. Otherwise this part matches because: The datasheet for AM29F800BB shows that the 2nd "B" in "29F800BB" means bottom boot, and the "E" in "-90EF" means TSOP48)