SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
7536 Group
MITSUBISHI MICROCOMPUTERS
26
Note on using USB mode
Handling of SE0 signal in program (at receiving)
7536 group has the border line to detect as USB RESET or EOP
(End of Packet) on the width of SE0 (Single Ended 0).
A response apposite to a state of the device is expected.
The name of the following short words which is used in table 7 shows
as follow.
TKNE: Token interrupt enable (bit 6 of address 20
16
)
RSME: Resume interrupt enable (bit 5 of address 20
16
)
RSTE: USB reset interrupt enable (bit 4 of address 20
16
)
Spec: A response of the device requested by USB Specification 1.0
SIE: Hardware operation in 7536 group
F/W: Recommendation process in the program
FEOPE: False EOP error flag (bit 2 of address 19
16
)
RxPID: Token interrupt flag (bit 7 of address 1F
16
)
Spec
SIE
F/W
Reset or resume
Reset interrupt
request
Reset interrupt
processing
Resume interrupt
processing
Table 5 Relation of the width of SE0 and the state of the device
Width of SE0
0
μ
sec.
0.5
μ
sec.
0.5
μ
sec.
2.5
μ
sec.
2.5
μ
sec.
2.67
μ
sec.
2.67
μ
sec.
Spec
SIE
F/W
Spec
SIE
F/W
Spec
SIE
F/W
Spec
SIE
F/W
Idle state
TKNE = X
RSME = 0
RSTE =1
Ignore
Keep counting suspend
timer
Not acknowledge
Keep alive
Initialize suspend timer
count value
Not acknowledge
Keep alive or Reset
may determine as keep
alive and Reset interrupt
Keep alive in case of no
interrupt request
Reset processing in case
of interrupt request
Reset
Reset interrupt request
Reset processing
End of Token in transaction
TKNE = 1
RSME = 0
RSTE =1
Ignore
Not detected as EOP(in
case of no detection EOP,
SIE returns idle state as
time out. FEOPE flag is
set.)
Not acknowledge
EOP
Token interrupt request
Token interrupt process-
ing execute
EOP or Reset
may determine as EOP
and Reset interrupt
RxPID = 1> Token
interrupt processing
RxPID = 0> Reset
interrupt processing
Reset
Reset interrupt request
Reset processing
End of data or handshake
in transaction
TKNE = 0
RSME = 0
RSTE = 0 or 1
Ignore
Not detected as EOP(in
case of no detection EOP,
SIE returns idle state as
timeup. FEOPE flag is
set.)
Wait for the next EOP flag
EOP
Set EOP flag
After checking the set of
EOP flag, go to the next
processing
EOP or Reset
may determine as EOP
and Reset interrupt
Continue the processing
in case of no interrupt
request
Reset processing in case
of interrupt request
Reset
Reset interrupt request
Reset processing
Suspend state
TKNE = 0
RSME = 1
RSTE = 0
State of device