Problems with 68B09ep chips

[paddythegreek]

I’ve bought a couple of these from eBay off a guy I’ve bought quite a bit of stuff off.
First 2 arrived wed and didn’t work in any of the 3 cpu boards I tried them in. One cpu is a pinled board I keep as a spare. All 3 work with the old 68B09e chip I have.
The guy has just sent me a couple more, different make and obviously different batch no.
Guys in the UK called Dan and speaks English not chinglish (I spoke to him on the phone).
Could these be c*ap Chinese copies. Ken
First 2 at top of pic

 

[AlanJ]

Is the data sheet spec the same for EF68B09P as it is for the MC68B09P ? There could be a subtle difference between the 2?

 

[paddythegreek]

As far as I’m aware as long as it’s 68B09 it should work. The old one of mine that works is an ef68B09EP

 

[Arv]

They look like copies to me from Aliexpress??

 

[AlanJ]

They look like copies to me from Aliexpress??

Are AliExpress ok Shaun or to be avoided?

 

[Arv]

It's hit and miss, sometimes you get lucky and get good stuff. Othertimes not so lucky...

 

[pinballtoys]

think you need the 'ep' (enhanced instruction set), don't think the standard 'p' will work

 

[Moonraker]

Not the first time someone has done this...

http://www.ukvac.com/forum/using-6809p-instead-of-6809ep_topic343142.html

So quite correct, 6809EP required, 6809P on its own will not work.

 

[AlanJ]

It's hit and miss, sometimes you get lucky and get good stuff. Othertimes not so lucky...

Ive got some obsolete chips I'm after and Aliexpress has them, so I'll take a punt, but at £5-£6 a chip - it's not a cheap punt !

 

[paddythegreek]

Erm the way I understood it is the B in the middle was crucial. A 6809 won’t work

 

[Moonraker]

Erm the way I understood it is the B in the middle was crucial. A 6809 won’t work

For standard IC's yes (eg 7400 seies saying different power ratings and speeds) but I think in the case of semiconductors I believe it's always the letters on the end of the number. In this case the E stands for external clock input; non E processors have an internal clock.
http://www.cpu-world.com/CPUs/6809/index.html

Jim @myPinballs can correct me on this.

 

[pinballmania]

The b is not relevant. The e at the end is. You need the e not the b.

 

[pinballmania]

In fact you need b and e

 

[myPinballs]

For standard IC's yes (eg 7400 seies saying different power ratings and speeds) but I think in the case of semiconductors I believe it's always the letters on the end of the number. In this case the E stands for external clock input; non E processors have an internal clock.
http://www.cpu-world.com/CPUs/6809/index.html

Jim @myPinballs can correct me on this.

Correct, the E means external clock input (not extra instructions) and the B means 2mhz max operation. The crystal used on the circuit will be 4x this speed so 8mhz in the case of pinball boards. The P at the end means Plastic case.

The reason you cant use a 68B09 is because of the external clock needs. the pinout between the 68B09 and the 68B09E are slightly different. The 68B09's pinout is more traditional and similar to the popular earlier 6802 ic, where it has an internal frequency gen and you just as a crystal externally with 2 caps. The chip then outputs the E and Q lines. On the 68B09E however you input the clock signal into the chip via the E and Q lines therefore creating the incompatibility between the 2 variants.

The B letter in the middle is part of a standard approach by many manufacturers and different cpus to signify max clock speed, so you ofter see letters A,B,C etc to note increasing frequency speeds. (Z80, 6502 for example)

I have plenty of good stock of 68B09E ics is anyone needs some. They are verified official stock sourced from specialists companies who deal with obsolete chips and official surplus. They wont be as cheap as ebay or ali express prices for a good reason. They work!