What do different I2C errors mean?

This is a clean v69 released flash - nothing special. I thought the v69 released version had 2250 jsvars now though? But I just reflashed and that's what I have.

>process.env
={
      "VERSION":"1v69",
      "BUILD_DATE":"Jul 29 2014",
      "BUILD_TIME":"16:29:45",
      "GIT_COMMIT":"b2386d6f0c48ac3970ba76e4e3dd4a6a48623469",
      "BOARD":"ESPRUINOBOARD",
      "CHIP":"STM32F103RCT6",
      "CHIP_FAMILY":"STM32F1",
      "FLASH":262144,"RAM":49152,
      "SERIAL":"33ffd305-41573033-33720843",
      "CONSOLE":"USB"
    }
>process.memory
=function () { [native code] }
>process.memory()
={"free":1754,"usage":46,"total":1800,"history":24,"stackEndAddress":536909768,"flash_start":134217728,"flash_binary_end":134438392,"flash_code_start":134443008,"flash_length":262144}
> 

I get the same error even if I disconnect the SDA and SCL lines....