Daily Archives: 2014-08-07

VoCore: SPI & MicroSD 7

Finally here is some good news. The SD card reply me.. 😀 Not sure whose problem now(might not the hardware problem), due to the reply is from spidev_test, the mmc driver still refuse its work. 🙂
PS: VoCore: SPI & MicroSD 6 is done yesterday actually. Just too busy to publish it.

Anyway, R4 R5 is removed from the dock.

This is the result.

spidev_test is in linux source, at /linux-3.10.49/Documentation/spi/spidev_test.c
And add this code to VOCORE.dts:spi@b00 to enable spidev driver.(replace that mmc-slot@1 if it exists)

spidev@1 {
    compatible = "linux,spidev";
    reg = <1>;
    spi-max-frequency = <1000000>;

spidev_test is simple, just send the SD boot code through the SPI to the microSD card.
I did not check whether or not the reply is correct yet 🙂 Have some food first, I guess there is no big issue.

VoCore: SPI & MicroSD 6

The factory contacted me today, the first 200pcs(beta, same as release one) will be done about Aug.12 and I need at least one day to test the new firmware, so there is only three days left to SPI CS1 driver, or we have to go plan B, leave that part alone for mass production then use update firmware to fix that.

Just did more test and check today.
There are some missing parts(it should not in openwrt code either)

SPI RESET REGISTER(address: 0x10000034)

SPI CS1 MODE REGISTER(address: 0x10000060)


This note is not that important, but this remind me, we have some SPI pin be pulled to GND in VoCore for the bootstrap!!!

They are SPI_CLK, SPI_MOSI. 🙂
There are push to GND…

And compare my dock circuit, they are pull to VCC…
Ye, HERE IT IS, my dock is not compatible with that VoCore.

That might the possible reason why the TF card do not reply me. The circuit is like this now…That 20K ohm resistor is planed to pull SPI_MOSI to VCC but now weaken the signal, due to that 4.7k ohm push it to GND… 0.8V happens to at the edge of VIL(Input LOW Voltage) of microSD card.