Datasheet

Section 16 USB Function Module (USB)
Page 1010 of 1408 R01UH0309EJ0500 Rev. 5.00
Sep 24, 2012
H8S/2456, H8S/2456R, H8S/2454 Group
(1) Transition from normal operation to stall
(1-1)
Transaction request
USB
Reference
(1-2)
STALL handshake
Stall
To (2-1) or (3-1)
Normal status restored
(1-3)
(2) When Clear Feature is sent after EPSTL is cleared
(2-1)
STALL handshake
Transaction request
(2-2)
Clear Feature command
Clear Feature command
(2-3)
(3) When Clear Feature is sent before EPSTL is cleared to 0
(3-1)
1. 1 written to EPSTL
by application
1. IN/OUT token
received from host
2. EPSTL referenced
1. Transmission of
STALL handshake
1. Internal status bit
cleared to 0
1. Internal status bit
cleared to 0
2. EPSTL not changed
1. 1 set in EPSTL
2. Internal status bit
set to 1
3. Transmission of
STALL handshake
1. EPSTL cleared to 0
by application
2. IN/OUT token
received from host
3. Internal status bit
already set to 1
4. EPSTL not
referenced
5. Internal status bit
not changed
To (1-2)
Internal status bit
0
EPSTL
0 → 1
Internal status bit
0
EPSTL
1
Internal status bit
0 → 1
EPSTL
1
Internal status bit
1
EPSTL
1 → 0
Internal status bit
1
EPSTL
0
Internal status bit
1 → 0
EPSTL
0
Internal status bit
1 → 0
EPSTL
1
Figure 16.19 Forcible Stall by Application