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mark_k · 24 April 2017, 20:55

How do you emulate >=2000 years in the MSM6242B? ComspecSCSI.device seems to treat year <78 as meaning 2000+year. In other words, for 2017 you'd need to have 17 in the year registers. So 7 in 1-year digit register, 1 in 10-year digit register. And it requires 10×(10-year reg) + (1-year reg) be <= 99.

cf. this in the 2.5.0b20 changelog entry:

Code:

- RTC year value is saved differently depending on OS version, Pre-2.0: RTC year value = current year - 1900,
  2.0+: year value = last 2 digits. Both methods supported when reading. WinUAE now uses pre-2.0 method if
  MSM clock chip (because this is the only type that KS1.x supports), 2.0+ if RF clock chip, previously always used -1900 method.

24 April 2017, 20:55	#95
mark_k Registered User Join Date: Aug 2004 Location: Posts: 3,343	How do you emulate >=2000 years in the MSM6242B? ComspecSCSI.device seems to treat year <78 as meaning 2000+year. In other words, for 2017 you'd need to have 17 in the year registers. So 7 in 1-year digit register, 1 in 10-year digit register. And it requires 10×(10-year reg) + (1-year reg) be <= 99. cf. this in the 2.5.0b20 changelog entry: Code: - RTC year value is saved differently depending on OS version, Pre-2.0: RTC year value = current year - 1900, 2.0+: year value = last 2 digits. Both methods supported when reading. WinUAE now uses pre-2.0 method if MSM clock chip (because this is the only type that KS1.x supports), 2.0+ if RF clock chip, previously always used -1900 method. Last edited by mark_k; 24 April 2017 at 21:04.