In SX Microcontrollers, SX/B Compiler and SX-Key Tool, mumcs01 wrote:

I'm doing a number of reads from an i2c clock, and it seems, on a hard reboot sometimes this read is getting cut short and operating as a write, scrambling things up. Below is the subroutine I made which is getting run 10 times in a row. 
[code]
sub rtc_read_byte
	temp2 = __PARAM1
	i2cstart RtcSda
	temp = RtcId
	temp.0 = 0
	i2csend rtcsda, temp
	i2csend rtcsda, temp2
	i2cstart RtcSda
	temp = RtcId
	temp.0 = 1
	i2csend rtcsda, temp
	i2cRecv rtcsda, temp, Nak
	i2cstop rtcsda
'	I think this below pause fixed it. 
	pause 30
	return temp
	endsub 
[/code]

Notice the pause I added, which seemed to solve this. My questions is, is there a mimimum time I should be waiting inbetween subsiquent read and write operations? I seem to remember hearing something like this before? Anyone know the minimum, or at least someone else seen this? It only seems to a happen after a hard reboot and on the FIRST read.

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