On 06.03.2018 22:13, Luca Bacci Bonotti wrote:
In your opinion is better the raspberry pi or ch341a to reach my goal?
I don't know. I doubt it makes much of a difference. If one fails, you can try the other. Though, the RPi is much faster.
Should I buy a breadboard for create better connections ?
Better than what?
Can you draw a schematic that I can follow?
Sigh, I guess I can.
Programmer SPI Flash
/CS ------------ /CS
MISO ---50-Ohm--- MISO
GND ------------ GND
MOSI ------------ MOSI
CLK ------------ CLK
VCC ------------ VCC \ `-10kOhm--- /WP \ `-10kOhm- /HOLD
This is about the minimum setup I'd use for a plain (unsoldered) chip. Resistor ratings may vary.
Nico
Il 6 mar 2018 21:55, "Nico Huber" nico.h@gmx.de ha scritto:
Hello Luca,
On 06.03.2018 07:25, Luca Bacci Bonotti wrote:
I tried with chip soldered and unsoldered. Same results.
same results? probably due to very different problems. Especially when the chip is not part of a circuitry (that might already take care), you have to connect all input pins of the chip. Also, very often, a series resistor at least on the MISO output is required.
I previously tried programming with raspberry PI but it was unable to see my chip. I have both CH341A and Raspberry Pi.
When you use the Raspberry Pi, make sure you set the `spispeed` parame- ter of linux_spi to something reasonable (I'd start trying around 1000, i.e. 1MHz), the default is OS dependent and often not reliable.
Where should i connect /HOLD /WP on the CH341A ?
/HOLD should be pulled up towards VCC (i.e. using a series resistor, 10kOhm maybe), state of /WP usually only matters when the chip has some write-protection set up, so either pull up towards VCC or down towards GND (if in doubt, up).
Nico