Portsdown 4 GPIO pins

[M0YDH]

Hello
I've spent little while this morning studying the Wiki pages https://wiki.batc.org.uk/Portsdown_4_GPIO_Connections and the original 2018 connections plus the 8 band cards. I hope to route pi 4 to connections on the Breakout board.

I can see SR select DO, D1 and D2. Shutdown, Tx LED and 3 lines to the ADF4351 (1K resistors) are there. 2 revisions have been made to move lines to redundant IQ terminal block.

Please can the breakout pin chart label connections to MSB, LSB and T? The latter was Digithin connection to pin 7 with10K resistor. These are essential for connection to switch and band decode cards without MENSA levels of mental agility . It is good to keep common names going.
Shutdown LED doesn't appear to exist. We may need multiples of the above connections to ease stuffing wires into terminal blocks?

I promise to add labelled photos of the finished breakout board to the Wiki.

Thanks 73
David M0YDH

[G7JTT]

Sorry Dave not sure on the pinout's but will ask on the net tonight encase someone is able to answer.

73 John

[M0YDH]

Thanks John. It's what are MSB, LSB, and Transverter connections called now? Then it'll be easier to connect the club cards.
73
David M0YDH

[G8GKQ]

Hi David

LSB is Band D0 and has moved to pin 32 on the Portsdown 4 (the old pin is used for RPi Hats and causes a conflict on the RPi 4).

MSB is Band D1 and remains on pin 35

Transverter is Band D2 and remains on pin 7.

Full details here: https://wiki.batc.org.uk/Portsdown_4_GPIO_Connections

Hope that helps

Dave

[M0YDH]

Thank you Dave. The symbol rate selections are DO, D1 and D2 in the original interconnect diagram but were bound for the FM board and latterly I think the 2 way rf switch. In the latest application we have D0, D1 and D2 to do all our switching and selection. 6 connections are reduced to 3 in P4. That's clearer.
73
David M0YDH.

[G8GKQ]

Hi David

I tend to refer to the individual lines within a parallel databus as D0....D7 (data 0 to data 7) even if there are only 2 or 3 lines. I should have made it clearer what the purpuse of each set of lines was.

So the Portsdown 2020 had SR Switching D0, D1 and D2, and also Band switching LSB (D0), MSB (D1) and Transverter (D2).

The Portsdown 4 simply has Band switching D0, D1 and D2. (Although I believe that the SR Switching lines might still be active - I don't recall disabling them).

Dave

[M0YDH]

Hi Dave
I added terminal numbers and labels found on the club GPIO breakout board to the P4 GPIO connections wiki page.https://wiki.batc.org.uk/Portsdown_4_GPIO_Connections
Follow up questions:-
Should pin 10 = Attenuator LE have a 1 K resistor like the ADF4351 connections on pins 10, 29 and new 33?

In relation to the 2 way RF switch https://wiki.batc.org.uk/2-Way_RF_Switchwhere the Pluto is connected to the F-M port, it would be very handy to know if the SR Band select pins on 36,37 and 38 are indeed still connected? They all get turned on / high, it says to switch in the Lime mini. It's unclear but I think SR D0 - pin 2 ; SR D1 to pin 3 and SR D2 to pin 4 on the card. I assume this isn't very important because it's all three or nothing. It works in my P2019.

I suggested that the P4 GPIO pin changes would suit unused Willow Breakout boards https://wiki.batc.org.uk/Willow_compone ... akout_card after reading its buried Wiki page. Extra connections had to be added to get to GPIO pins 27 and 28 to which P4 must not be connected . I've one of these from the early days kicking about.

73

David M0YDH