Datasheet

DS1992/DS1993
7 of 17
Figure 6. MEMORY FUNCTIONS FLOW CHART
Master TX Memory
Function Command
Y
DS199x sets Scratchpad
Offset = (T4:T0) and
Clears (PF, OF, AA)
DS199x sets (E4:E0)
= Scratchpad Offset
DS199x Increments
Scratchpad Offset
Bus Master TX
TA1 (T7:T0)
Bus Master TX
TA2 (T15:T8)
Master TX Data Byte
To Scratchpad Offset
Bus Master
TX Reset
?
N
0FH
Write
?
Scratchpad
N
Bus Master
TX
Data
?
Y
N
PF = 1
N
Y
Bus Master
TX Reset
?
To Figure 6
Second Part
Bus Master RX
TA1 (T7:T0)
Bus Master RX
TA2 (T15:T8)
Master RX Ending
Offset with Data
Status (E/S)
DS199x Sets
Scratchpad
Offset=(T4:T0)
Bus Master
TX Reset
?
DS199x Increments
Scratchpad Offset
Y
Master RX Data
Byte From
Scratchpad Offset
N
N
Scratch
-
pad Offset =
11111b ?
Y
Y
Scratchpad
AAH
Read
?
Bus Master
RX "1"s
From Figure 6
Second Part
OF = 1
Scratch
-
pad Offset =
11111b ?
N
Partial
Byte Written
?
N
Y
Y
Y
DS199x TX
Presence Pulse
(See Figure 9)