HD64F3437TF16 Datasheet, PDF (201/752 Pages) Hitachi Semiconductor – 12 V must not be applied to the S-mask model (single-power-supply specification), as this may permanently damage the device.

(1) Upper byte read
CPU reads
data H'AA
Bus
interface
Module data bus
TEMP
[H'55]
(2) Lower byte read
CPU reads
data H'55
Bus
interface
FRCH
[H'AA]
FRCL
[H'55]
Module data bus
TEMP
[H'55]
FRCH
[]
FRCL
[]
Figure 8.3 (b) Read Access to FRC (when FRC Contains H'AA55)
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