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• Broadcom BCM2712 2.4GHz quad-core 64-bit Arm Cortex-A76 CPU, with cryptography extensions, 512KB per-core L2 caches and a 2MB shared L3 cache
• VideoCore VII GPU, supporting OpenGL ES 3.1, Vulkan 1.2
• Dual 4Kp60 HDMI? display output with HDR support
• 4Kp60 HEVC decoder
• LPDDR4X-4267 SDRAM (4GB and 8GB SKUs available at launch)
• Dual-band 802.11ac Wi-Fi?
• Bluetooth 5.0 / Bluetooth Low Energy (BLE)
• microSD card slot, with support for high-speed SDR104 mode
• 2 × USB 3.0 ports, supporting simultaneous 5Gbps operation
• 2 × USB 2.0 ports
• Gigabit Ethernet, with PoE+ support (requires separate PoE+ HAT)
• 2 × 4-lane MIPI camera/display transceivers
• PCIe 2.0 x1 interface for fast peripherals (requires separate M.2 HAT or other adapter)
• 5V/5A DC power via USB-C, with Power Delivery support
• Raspberry Pi standard 40-pin header
• Real-time clock (RTC), powered from external battery
• Power button

For those who have cases without a lot of height, especially with some of the V12 boards having connectors at the top, I came up with idea to mount the boards at 45 degree angles.??

It was beyond my capabilities in autocad, but fortunately my son happens to teach a class at NC state and was able to help me out.? It also make probing the board easier.



You'll need to bolt the holder down because the weight of the board will cause it to flop over, but the board does not need to be bolted to the holder.

You can find the stl file here in the files section.

/g/SoftwareControlledHamRadio/files/holder%20v2%20v5.stl

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Some more information on how I have implemented and used the RA8875 Keypad interface.

The original RA8875 library does not have support for the Keypad so I have modified it and made it available on my github page (hopefully at some time they will integrate the changes into the original but have not done so yet):

I added the following functions:

??? int KeypadInit(bool scanEnable, bool longDetect, uint8_t sampleTime, uint8_t scanFrequency,
???????????????????????????? uint8_t longTimeAdjustment, bool interruptEnable, bool wakeupEnable);

???? bool KeypadHit(void);

???? uint8_t KeypadGetKey(void);

???? void SetKeyMap(const uint8_t * CodeList = NULL);

The documentation is fairly limited in RA8875 Specs, but the sampleTime value can be between 0 and 3, the scanFrequency can be between 0 and 7 and the longTimeAdjustment can be between 0 and 3.? I am currently setting them all to 0 which seems to work well. I have also not tried using interruptEnable or the wakeupEnable options yet. It currently does not handle multiple concurrent presses although the RA8875 can handle up to 3 buttons being pressed at the same time. It will always return the highest button.

??? tft.KeypadInit(true, false, 0, 0, 0, false, false);

To test if a key has been pressed you can call KeypadHit (although it is not necessary as KeypadGetKey will return 255 (0xFF) if none has been pressed):

??? bool KeypadHit(void);

which returns true if a key has been pressed, and calling

??? uint8_t KeypadGetKey(void);

will return the key that was pressed (default of 1..20).

You can change the key map by using:

??? void SetKeyMap(const uint8_t * CodeList = NULL);

and passing in an array of values for the keys to be returned (note that the first and last are not used):

??? static const uint8_t my_keymap[22] = {
?? ? ?? 0,
??????? 0,? 4,? 8, 12, 16,
??????? 1,? 5,? 9, 13, 17,
??????? 2,? 6, 10, 14, 18,
??????? 3,? 7, 11, 15, 19,
??????? 255
??? };

I have the T41-EP 18 switches wired like this (just not connected the 2 extra that are available on the keypad) and use the above keymap which will return 0..19 to match the existing code:

It is fairly easy to change the code in Button.cpp to handle polling the Keypad interface.

-- John G0ORX

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There is an easier way to implement the keys using a keypad matrix.

The 5" display board with the RA8875 controller that is being used has a keypad matrix interface built into it but is not currently being used.

My latest version of a front panel is using this. I had to make some changes to the RA8875 library to include the code to read the data from the Keypad. You also have to add some 100k resistors and open up some jumpers on the board.

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Nice bezel on the display.?

Larry

This is a seat of the pants checkout- plug a set of earbuds into the QSE jack (exciter) and while running the test, pull off L and then R. The channel should drop.?

Then if you have a scope, probe the QSE outputs from the op amps to the FST3253, should see the same behavior if you disable one or the other.?

This looks like L and R are shorted together or one is missing.?

Larry
KB3CUF