25 Oct
2007
25 Oct
'07
12:50 a.m.
Tony Duell schrieb:
Actually, it's TTL chips. IIRC the kits came out
in the mid-1970s.
There's a schematic of the logic module in the manual (one of the frw
pages I can understand, since the manual is in German, but a schematic is
much the same in any language). There are 3 chips in the module, all with
Philis-type numbers. An FJH241 (looks like a 7404), FJH151 (7451) and
FJH231 (7401)
Actually, they don't just look like the mentioned 74xx equivalents, they
are almost (FJH241 is rather 5404).
This xxxNNN convention was some European attempt to standardize the
various logic families in the 70s;
I think this came from JEDEC as a joint venture of Siemens, Philips, and
some other vendors).
The idea was basically to have the first letter to describe the logic
family, the second a temperature range or
a sub family (e.g. Z=noise immune logic with 12Vcc), the third a
functional category. The three digit number then
refers to the actual circuit. So, an FLH101 was a TTL (F) with
temperature range 0..70degC (L), and
combinational circuit (H). The number here refers to 4 totem pole NAND-2
gates -> so this is the well-known 7400.
J in the third place denotes some flip flop or counter, K is a monoflop,
L is a decoder (e.g. 74141, 7445, 7447).
I have to look up the complete convention in some old Siemens data books.
Almost all of these Fxx types directly map to 49xxx, 54xx, 74xx, and
75xxx types.
This numbering scheme apparently wasn't very successful, and was
silently dropped some years later.
--
Holger