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akavel
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When programming an Atmel microchip over SPI (ISP), what external clocking do I have to provide to programee? Does it have to match programmer's internal clock frequency, or can be totally different because SPI CLK line will be used? If the latter, then are there any limitations on SPI CLK freq I will use on programmer, or will programee auto sync to whatever goes? Also, do I maybe need to disconnect any possible external clock from programee? Also, do I have to set any freq fuses on programee?

I'm newbie to EE, so I'd be grateful for thorough answers.

(For programmer I intend to try using a Raspberry Pi's SPI interface)

edit: uh, yes, I mean an AVR microcontroller, sorry and thanks.

When programming an Atmel microchip over SPI (ISP), what external clocking do I have to provide to programee? Does it have to match programmer's internal clock frequency, or can be totally different because SPI CLK line will be used? If the latter, then are there any limitations on SPI CLK freq I will use on programmer, or will programee auto sync to whatever goes? Also, do I maybe need to disconnect any possible external clock from programee? Also, do I have to set any freq fuses on programee?

I'm newbie to EE, so I'd be grateful for thorough answers.

(For programmer I intend to try using a Raspberry Pi's SPI interface)

When programming an Atmel microchip over SPI (ISP), what external clocking do I have to provide to programee? Does it have to match programmer's internal clock frequency, or can be totally different because SPI CLK line will be used? If the latter, then are there any limitations on SPI CLK freq I will use on programmer, or will programee auto sync to whatever goes? Also, do I maybe need to disconnect any possible external clock from programee? Also, do I have to set any freq fuses on programee?

I'm newbie to EE, so I'd be grateful for thorough answers.

(For programmer I intend to try using a Raspberry Pi's SPI interface)

edit: uh, yes, I mean an AVR microcontroller, sorry and thanks.

Source Link
akavel
  • 427
  • 1
  • 5
  • 12

Clocks setup when programming Atmel via ISP?

When programming an Atmel microchip over SPI (ISP), what external clocking do I have to provide to programee? Does it have to match programmer's internal clock frequency, or can be totally different because SPI CLK line will be used? If the latter, then are there any limitations on SPI CLK freq I will use on programmer, or will programee auto sync to whatever goes? Also, do I maybe need to disconnect any possible external clock from programee? Also, do I have to set any freq fuses on programee?

I'm newbie to EE, so I'd be grateful for thorough answers.

(For programmer I intend to try using a Raspberry Pi's SPI interface)