The PIC16F88x are out. Finally say hello to the new 16F87x

[William At MyBlueRoom]

I actually got samples today of the new PIC16F886 and the Inchworm ICD2 supports them
Finally the venerable 16F877 and it's brothers can slowly retire from new design. (Nothing retires quickly from Microchip).

They are pin compatible with the 16F87x series ICs, they just have even more features such as FINALLY a built in 8 speed osc, so two more I/O pins are available RA6,7. And like most new silicon they're cheaper than the 16F87x they replace.

Edit: I jumped the gun. MPLAB 7.50 has only beta support (not quite right yet) with these new chips. I'm sure an update will be out soon. It's having a problem verifing it.

Looks like the PICKIT2 supports it fine too. PICStart Plus no support yet.

Edit 2, looks like I have a bad ZIF socket on my first Firefly, The Aries socket version works fine with the 16F886!

 

[Mike - K8LH]

That's good news Bill. Thanks. Just ordered samples.

Happy Holidays. Mike

 

[Mike - K8LH]

Received samples of the '886 in the I/SO package (SOIC-28) but it seems shipment of the '886 and '887 samples in the DIP packages has been deferred to some time in January. Bummer!

Happy Holidays. Mike

 

[William At MyBlueRoom]

Received samples of the '886 in the I/SO package (SOIC-28) but it seems shipment of the '886 and '887 samples in the DIP packages has been deferred to some time in January. Bummer!

Happy Holidays. Mike

I guess I preordered and got mine already in DIP form.

 

[art-666]

seen this on e-bay
if you can't wait for microchip

**broken link removed**

 

[William At MyBlueRoom]

LOL I don't think Microchip ran short at 15.

I'm working on the Robin RS485 terminal

• PIC16F887 (or with crystal 16F876)
• RS485
• LCD 2x16 with backlight
• 4x4 keypad (1x4 built in)
• DS1388 RTC SOIC
• 24xxx SOIC EEPROM
• XBee (ZigBee) radio
• user port

Building it for a client that agreed to release the board. Small too 95mm x 45mm (Hammond 1591A case)
**broken link removed**

 

[GRC]

Do you guys think the 16F88x will have the same issue as the 16F88. By this I
mean the internal OSC and MCLR when used in a certain combonation, it will
cause a conflict and make erasing difficult?

Gordon

 

[William At MyBlueRoom]

Do you guys think the 16F88x will have the same issue as the 16F88. By this I
mean the internal OSC and MCLR when used in a certain combonation, it will
cause a conflict and make erasing difficult?

Gordon

It's possible, that's why I don't use the pin. I am using the RB6 & 7 pins for a keypad.

 

[Mike - K8LH]

Do you guys think the 16F88x will have the same issue as the 16F88. By this I
mean the internal OSC and MCLR when used in a certain combonation, it will
cause a conflict and make erasing difficult?

Gordon

That's only a problem with programmers that don't fully control VDD and VPP to the target PIC. My melabs Serial Programmer doesn't have a problem with those chips using that configuration.

Actually, my Serial ICD2 clone (modified Stolz design) was able to reprogram a 12F683 in that configuration (INTOSC & MCLR off). Not sure if it was because I added VDD switching circuitry or not but it worked.

Good luck. Regards, Mike

 

[William At MyBlueRoom]

That's only a problem with programmers that don't fully control VDD and VPP to the target PIC. My melabs Serial Programmer doesn't have a problem with those chips using that configuration.

Actually, my Serial ICD2 clone (modified Stolz design) was able to reprogram a 12F683 in that configuration (INTOSC & MCLR off). Not sure if it was because I added VDD switching circuitry or not but it worked.

Good luck. Regards, Mike

I didn't want to add the switched VDD circuit because I didn't want to add a 1A switch.

 

[Nigel Goodwin]

Actually, my Serial ICD2 clone (modified Stolz design) was able to reprogram a 12F683 in that configuration (INTOSC & MCLR off). Not sure if it was because I added VDD switching circuitry or not but it worked.

That's the reason, the only reason the InchWorm can't do it is because it doesn't switch Vdd - but it's not a very common practice for ICSP.

 

[Mike - K8LH]

I didn't want to add the switched VDD circuit because I didn't want to add a 1A switch.

I didn't use a 1-amp VDD switch, just a little BS250P P-channel MOSFET in a TO-92 package.

I suppose a jumper could be added to take it out-of-the-circuit and select your always-on VDD power source.

 

[mramos1]

Nigel:

It is not common but for me after the second time, I now check the __config before I program then chip. In my case, the compiler set it wrong (well I did not set it to be honest). I used and old programmer to fixed it. Maybe a week later, I did it again.

Now I check it everytime.

GRC:

It is just one of a couple things on the PIC you learn. I just say MCLR belongs to ICD2/Microchip, and pull it up.

 

[alamy]

That's only a problem with programmers that don't fully control VDD and VPP to the target PIC. My melabs Serial Programmer doesn't have a problem with those chips using that configuration.

Actually, my Serial ICD2 clone (modified Stolz design) was able to reprogram a 12F683 in that configuration (INTOSC & MCLR off). Not sure if it was because I added VDD switching circuitry or not but it worked.

Good luck. Regards, Mike

if i'm using inchworm design (modified stolz) that take 12.5v from max232, it's work to add BS250P P-channel MOSFET ?..

 

[ljcox]

Could someone please tell me why it is necessary to switch Vdd?

I did not bother doing it in my programmer but I have only ever programmed 16F devices.

 

[Nigel Goodwin]

Could someone please tell me why it is necessary to switch Vdd?

I did not bother doing it in my programmer but I have only ever programmed 16F devices.

Some devices (like the 16F628) allow you to allocate the MCLR pin as an extra I/O pin, and can use an internal oscillator - giving 16 I/O pins on an 18 pin package. As there's then no reset pin you can't reset the PIC in order to access programming mode, so you need to switch Vdd OFF to stop the PIC running, THEN reapply Vdd and VERY quickly switch MCLR to 13V, BEFORE the internal oscillator can start running.

So if you don't switch Vdd, have allocated MCLR as an I/O pin, and have enabled the internal oscillator (as my tutorials do) then you can't program the chip after the first time.