reprap:anet:anet_mainboard_overclocking

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reprap:anet:anet_mainboard_overclocking [2018/01/04 14:41]
gmarsh23 [Crystal selection and replacement]
reprap:anet:anet_mainboard_overclocking [2018/01/09 03:14]
gmarsh23 [Crystal selection and replacement]
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 === Choosing a new crystal === === Choosing a new crystal ===
  
-The Anet V1.0 board requires a "​HC-49S"​ surface mount crystal. Choose one with an 18 to 22pF load capacitance,​ as this best matches the load capacitance provided on the Anet board.+The Anet V1.0 board requires a "​HC-49S"​ surface mount crystal. Choose one with a 12pf load capacitance,​ as this best matches the load capacitance provided on the Anet board.
  
 Here are some suitable crystal frequencies to choose from: Here are some suitable crystal frequencies to choose from:
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 | 27MHz | +68.8% | +35% | May be unstable.\\ significant baud rate error (see below)\\ Can be salvaged from video equipment (DVD players, etc) | | 27MHz | +68.8% | +35% | May be unstable.\\ significant baud rate error (see below)\\ Can be salvaged from video equipment (DVD players, etc) |
  
-If you're using the USB interface of the printer, using Octoprint for example, the crystal you choose affects how accurate the baud rate of the Mega1284P'​s UART will be at a given baud rate. For reliability reasons this should not exceed +-5%; ideally this value is less than +-2.5%. If you only printing from the SD card, this isn't an issue.+Note: If you're using the USB interface of the printer, using Octoprint for example, the crystal you choose affects how accurate the baud rate of the Mega1284P'​s UART will be at a given baud rate. For reliability reasons this should not exceed +-5%; ideally this value is less than +-2.5%. If you don't plan on using the printer'​s USB connection, this isn't an issue.
  
 ^ Crystal freq (below), baud (right) ^ 115200 ^ 230400 ^ 250000 ^ 460800 ^ 500000 ^ 921600 ^ 1000000 ^ 1500000 ^ ^ Crystal freq (below), baud (right) ^ 115200 ^ 230400 ^ 250000 ^ 460800 ^ 500000 ^ 921600 ^ 1000000 ^ 1500000 ^
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 === Downloading and compiling Optiboot === === Downloading and compiling Optiboot ===
 +
 +**If you're using a 24MHz crystal, just copy this paste and save it as a .hex file:** https://​pastebin.com/​Tv1EHPmc
  
 You'll need to download and compile Optiboot first. More information can be found on the Optiboot github page: https://​github.com/​Optiboot/​optiboot/​wiki/​CompilingOptiboot You'll need to download and compile Optiboot first. More information can be found on the Optiboot github page: https://​github.com/​Optiboot/​optiboot/​wiki/​CompilingOptiboot
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 Use the following options to compile it for the Anet V1.0 board. Change the "​24000000"​ value to the frequency of the crystal you're using in Hz - don't forget the L on the end.  Use the following options to compile it for the Anet V1.0 board. Change the "​24000000"​ value to the frequency of the crystal you're using in Hz - don't forget the L on the end. 
  
-  make AVR_FREQ=24000000L BAUD_RATE=57600 LED=A4 ​atmega1284p ​UART=0+  make AVR_FREQ=24000000L BAUD_RATE=57600 LED=A4 UART=0 ​atmega1284p
  
 Save the .hex file for later. Save the .hex file for later.
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 === Flashing new firmware === === Flashing new firmware ===
  
-Use AVRDUDE:+Use AVRDUDE ​to set the fuse/​lockbit values on the processor, then program in the new bootloader: 
 + 
 +  avrdude -p atmega1284p -c <your programmer>​ -U hfuse:​w:​0xDE:​m lfuse:​w:​0xf7:​m efuse:​w:​0xfc:​m lock:​w:​0x2f:​m 
 +  avrdude -p atmega1284p -c <your programmer>​ -U flash:​w:​optiboot_atmega1284p.hex
  
-  avrdude -p atmega1284p -c <your programer>​ -U flash:​w:​optiboot_new.hex+The fuse values given move the bootloader start address to 0xFE00/​0x1FC00 (word/byte) which frees up 3K of application space from the bootloader section. The lock bits prevent the bootloader from overwriting itself and bricking the board, if you send in a code image which is big enough to expand into the bootloader space.
  
 Once the board is programmed, connect the board to your PC via its USB connection, and attempt to "​ping"​ the new bootloader with the following avrdude command. Change "​COM1"​ to the serial port corresponding to the printer on your computer. Once the board is programmed, connect the board to your PC via its USB connection, and attempt to "​ping"​ the new bootloader with the following avrdude command. Change "​COM1"​ to the serial port corresponding to the printer on your computer.
  • reprap/anet/anet_mainboard_overclocking.txt
  • Last modified: 2018/12/02 01:27
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