MA28139 Datasheet, PDF (17/34 Pages) Dynex Semiconductor – OBDH Bus Terminal

MA28139
Bit Position
RIRSYNC
RIRCLK
RIRDATA
RIRVAL
IRCLK
TRCLK
CTCLK
CHADD(0:7)
MODS16
DIGIN
DATARRT
ENRRT
Bit Position
RIRSYNC
RIRCLK
RIRDATA
RIRVAL
IRCLK
TRCLK
CTCLK
CHADD(0:7)
MODS16
DIGIN
DATARRT
ENRRT
Note 1: One 16-bit Digital Serial Acquisition command takes 2 Interrogations to complete. A succeeding Acquisition or Switch
Closure command of any type is hence not possible and forms a protocol violation. The second command of such a sequence
will be rejected.
Note 2: For any acquisition command to be decoded, the evaluated Memory Load Address must be zero. An evaluated Memory Load
Address of non-zero does not imply data acquisition.
Note 3: The Memory Load Address which is evaluated for decoding and addressing usage may vary from 3 to 5 bits.
If (EXTMLA1 = 1) and (EXTMLA2 = 0), the Memory Load Address field is extended to 4 bits and bit 11 of the Interrogation will be
treated as MLA(1).
If (EXTMLA2 = 1), the Memory Load Address field is extended to 5 bits and bits 10 and 11 of the Interrogation will be
treated as MLA(0:1).
Any Interrogation bits treated as Extended Memory Load Address bits will not be treated as Terminal Address bits; this facility is
intended for 2x or 4x size expansion provided that up to 4 consecutive Terminal Addresses can be used.
Note 4: The 16-bit Digital Serial Acquisition command response is always 21 bits in length; the Destination Address is simply
copied from the Interrogation into the Response.
Figure 15: 16-Bit Digital Serial Acquisition Waveforms
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