Extra GPIOs modules & PinOut For display + Panda II

Hi everybody,
I’ve started since few days with Panda II (working professionnaly with Rabbit & PIC)…
I know now how to write textes on the display,
how to show images on the display,
how to generate sound, commands,
how to communicate serially,
how to read analog input & temperature,
and how to use button events …


  1. Where I can have the PinOut of the Display to use remaining GPIOs ,
  2. Is there a cheaper solution than adding others Panda II modules fors extra inputs ???
    My project uses actually 2x Panda II as extension,
  3. Does GHI produce extra GPIOs modules (SPI,…) for Panda II ?

Thanks for help

How many extra IOs do you need?
How many IOs do you need total?

Welcome to the community.

15 to 20 should be ok !! max 30

Panda II has 53 IOs so I am not sure what you need.

I’m usinf the display (40 I/O-? are then used) … and I need 15 to 30 extra I/O
Actually : 6xDig In, 7xDig Out, 2xtemp. sensor, 2xCurrent sensor, 1xVoltage sensor, 1xBuzzer
Need : 15 to 30 extra Dig In & Dig Out … for commanding & controlling emergency power’s circuits

& I would prefer using only one Panda II

Not true. I bet you didn’t look at the display documentation :slight_smile:

What kind of display are you using?

I’m using a monochrome 128x64 graphic display and it uses 11 pins for the display (plus 1 for backlight).

If your project is anything like mine, you’ll run out of program space long before you run out of IO’s on the Panda. It is limited in ROM and RAM - so be careful of taking on too much with such a small device.

FEZ Ultimate Kit

Display used = Display included : FEZ Touch, Part #: GHI-FTOUCH-262
"Plug and play in the 40 pin female header. The LCD uses many of the 40-pin female header. The unused pins are exposed on UEXT and EXT headers.".
Then there are few unused pins reported at the bottom of the display for external use… what is the PinOut please ?

For the memory :

  1. The sub-systems equiped with Panda II need extra GIOs that are just transferrring Input (order) to Output (Commands) excepted in case of mains supply’s failure where all the Ouptut must be on at the same time (then few software for many hardware)

  2. The master central system monitoring all the sub-systems (equiped with Panda II) will be equiped with Spider (still in box & not tested for the moment)

Here is the PinOUt of the display & Touch for Panda II

Display : 27 PIN Used
Touch Display needs :

Pin01-VCC 3.3V VCC
Pin02-GND Ground
Pin03-LCD chip select CS
Pin05-LCD register select RS
Pin06-Back_Light Back light
Pin07-LCD write strobe WR
Pin08-D_CS Touch chip select
Pin09-LCD read strobe RD
Pin10-D_Busy Touch busy pin
Pin11-LCD reset RESET
Pin17-Touch pen interrupt D_Penirq
Pin18-GND Ground
Pin19-Touch clock/SPI Clock D_CLK
Pin21-Touch data out/SPI MISO D_OUT
Pin23-Touch data in/SPI MOSI D_DIN
Pin29-LCD data bit 7 DB7
Pin30-DB6 LCD data bit 6
Pin31-LCD data bit 5 DB5
Pin32-DB4 LCD data bit 4
Pin33-LCD data bit 3 DB3
Pin34-DB2 LCD data bit 2
Pin35-data bit 1 DB1
Pin36-DB0 LCD data bit 0
Pin38-GND Ground
Pin39-+5V +5V
Pin40-VCC VCC 3.3V

Here is the Pins unsued in the display & Touch for Panda II
Remaining : 13 PIN Unused
PIN04 Unused
PIN12 Unused
PIN13 Unused
PIN14 Unused
PIN15 Unused
PIN16 Unused
PIN22 Unused
PIN24 Unused
PIN25 Unused
PIN26 Unused
PIN27 Unused
PIN28 Unused
PIN37 Unused

The Pin Unused reported on plug are : only 11 PIns

UEXT Pin Header Mapping : 5 Pins

Pin013.3 Volt out VCC
Pin02 GND Ground
Pin03 D39 PIN24
Pin04 PIN22 D37
Pin05 D43 PIN28
Pin06 PIN26 D41
Pin07 D36 USED
Pin08 D38 USED
Pin09 D35 USED
Pin10 PIN37 D52

EXT Pin Header Mapping : 6 Pins

Pin01 3.3 Volt out VCC
Pin02 5V 5 Volts In/Out
Pin03 Ground GND
Pin04 PIN4 D21
Pin05 D29 PIN12
Pin06 PIN13 D30
Pin07 D31 PIN14
Pin08 PIN15 D32
Pin09 D33 PIN16
Pin10 GND Ground

This is not enoughht for my project …

Please, Is there a cheaper solution than adding others Panda II modules fors extra inputs
My project uses actually 2x Panda II as extension ?

Does GHI produce extra GPIOs modules (SPI,…) for Panda II ?

Please, Help

Hello again,
I’ve found on a German site : http://www.watterott.com/de/I/O-40-Extender

I/O 40 Extender GHI-IO40EXT-189 (Two JST cables are included).
Add 40 more digital IOs to your next project.
Need more I/Os? Then this extender is for you.
Using I2C, you can add 40 I/Os to your FEZ.
If that isn’t enough, you can also chain up to eight for a maximum of 320 I/Os!

It seems great & really what I need !

GHI : offers Drivers & Brochure, but no pricing ?
Can you Help me ?

Sorry to bother you, but I would like to realise that sensitive project with GHI. …

Nobody :smiley: ??? :smiley:

You said 20 IOs and you have 20 IOs, no?!

Please tell us exactly what you need instead of posting multiple questions.

Hello again,
I’m using the display (27 I/O are then used) … and I need 15 to 30 extra I/O

Actually : 46 I/O are Used (Commands & Controls & LCD)
(6xIn + 7xOut + 2xAn Temperature + 2xAn Current + 1xAn Voltage, + 1xPWM Buzzer + 27 PIN Used for Touch Display), (I’m provisoirly using a Component Shield 3-pin E-Block instead of FEZ Connect Shield to gain I/O)

Left : 11 through LCD, (Communication ports not traited yet!)

Need : Minimum 8xIn & 8xOut // Max. 15xIn & 15xOut (for Load commutation). The solution would be I/O 40 Extender GHI-IO40EXT-189 : It would give me Max. 15xIn & 15xOut + 5xIn & 5xOut Extra IO !

Is I/O 40 Extender GHI-IO40EXT-189 avalaible & at which price ??? :o

You can use any $0.10 shift register and each one will give you 8 IOs.

Something like this EZ-Expander

Then you don’t produce anymore GHI-IO40EXT-189,

Thanks a lot for your answer …

Is this module compatible wtih Connect Shield ???
& Is it really safe ? (it is simple 595 shift register instead of solid I2C communication !)


Concerning GPIOs extension :

Is it possible to Use all the I/O of the FEZ MINI ?

I mean : Instead of using the SD card option using the reserved Pins as simple GPIOs …
In that case FEZ MINI should be a very nice Sub-System for my Panda_II by adding the laking GPIOs …
(Communication & Confirmation Using RS2332, RS485,SPI OR CAN).
I want to be sure that these Pins can be used as GPIOs before buying some…

Thanks for your fast reply I’m Really under stress !
Best regards

Some body ? ::slight_smile:

Yes you can use them all. Have you tried it?

Thanks for the good news…

I’ve only bought 4 x Panda_1 + 1 kit ultimate + (1x Spider kit For the master).
I have not tested FEZ MINI yet… I wanted to be sure before,

I’ll buy now some FEZ MINI to test them (they are so small! and still competitive, Great Idea !)

I have caculated that (if the project works) 1 x FEZ PANDA_II + 1 x FEZ MINI for each SubSystem should represent only 30% !!! of the price of my actual developpments with PIC MCUs ! (with the 70% left, I will add some features to the power circuitry), but only if the project works…

Thanks again …