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Problems with 2 SPI Slaves
The MAX7221 are daisy chained so they appear as 1 logical SPI device   regards  
Thursday, 5 September 2019 - 12:13
Problems with 2 SPI Slaves
Its been running for about 6 weeks on and off at 50 x expected speeds using the 4 x MAX7221's without problem so I don't think it's marginal.  It's TWI driven so I'm looking...
Thursday, 5 September 2019 - 11:20
Problems with 2 SPI Slaves
No,  thought the board was good to go after a month of testing the MAX.  wired some tiny cables on instead to get a look at the signals.  It's like fixing a...
Wednesday, 4 September 2019 - 20:02
Problems with 2 SPI Slaves
Yes that's all I have for the init.  To be honest it's been working fine with the MAX7221's for some time.  It's just been the addition of another slave.  MCP runs...
Wednesday, 4 September 2019 - 19:59
CCL, LUTS and Encoders
The speed won't be that fast.  5 detents/second, so 20?   regards  
Tuesday, 3 September 2019 - 20:13
Problems with 2 SPI Slaves
That's what I've done.  The data sheet speaks of a required delay after dropping the pin, and I'm allowing 1ms which should be plenty it's still unreliable.  The...
Tuesday, 3 September 2019 - 19:58
Problems with 2 SPI Slaves
I did wonder about the CS state of that port.  Have to say I didn't fully understand that section of the data sheet.   regards  
Tuesday, 3 September 2019 - 16:25
Problems with 2 SPI Slaves
I'm using studio, the lack of colours is just my bad pasting.   It's a little difficult to attach any probes on the board as it's all SMD.  I guess I'll have to...
Tuesday, 3 September 2019 - 16:01
Solved: atmega328p using an external oscillator
OMG.  You're absolutely right.  It says 100MHZ on the chip too (very small).  Duh!.  Packet they came is says 20MHz.  Lesson learnt, don't assume the...
Thursday, 29 August 2019 - 14:02
Solved: atmega328p using an external oscillator
scope looks ok, but I'm no expert   regards
Thursday, 29 August 2019 - 13:47
Solved: atmega328p using an external oscillator
Thanks,   Made new board with new chip.  Worked until I set clock to Ext clock, then unreachable though it is flashing a led but very slowly (blink test program I...
Wednesday, 28 August 2019 - 12:27
Solved: atmega328p using an external oscillator
Thank you.   My final question though, how does the chip know the clock is at 20Mhz? Surely there's more than simply setting F_CPU ?   regards  
Tuesday, 27 August 2019 - 20:04

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