Datasheet
PIC16(L)F1454/5/9
DS41639A-page 316 Preliminary 2012 Microchip Technology Inc.
FIGURE 26-5: BUFFER DESCRIPTOR TABLE MAPPING FOR BUFFERING MODES
TABLE 26-2: ASSIGNMENT OF BUFFER DESCRIPTORS FOR THE DIFFERENT
BUFFERING MODES
Endpoint
BDs Assigned to Endpoint
Mode 0
(No Ping-Pong)
Mode 1
(Ping-Pong on EP0 OUT)
Mode 2
(Ping-Pong on all EPs)
Mode 3
(Ping-Pong on all other EPs,
except EP0)
Out In Out In Out In Out In
0 0 1 0 (E), 1 (O) 2 0 (E), 1 (O) 2 (E), 3 (O) 0 1
1 2 3 3 4 4 (E), 5 (O) 6 (E), 7 (O) 2 (E), 3 (O) 4 (E), 5 (O)
2 4 5 5 6 8 (E), 9 (O) 10 (E), 11 (O) 6 (E), 7 (O) 8 (E), 9 (O)
3 6 7 7 8 12 (E), 13 (O) 14 (E), 15 (O) 10 (E), 11 (O) 12 (E), 13 (O)
4 8 9 9 10 16 (E), 17 (O) 18 (E), 19 (O) 14 (E), 15 (O) 16 (E), 17 (O)
5 10 11 11 12 20 (E), 21 (O) 22 (E), 23 (O) 18 (E), 19 (O) 20 (E), 21 (O)
6 12 13 13 14 24 (E), 25 (O) 26 (E), 27 (O) 22 (E), 23 (O) 24 (E), 25 (O)
7 14 15 15 16 28 (E), 29 (O) 30 (E), 31 (O) 26 (E), 27 (O) 28 (E), 29 (O)
Legend: (E) = Even transaction buffer, (O) = Odd transaction buffer
2000h
EP0 OUT
Descriptor
PPB<1:0> = 00
No Ping-Pong
Buffers
EP0 IN
Descriptor
EP1 OUT
Descriptor
EP1 IN
Descriptor
EP7 IN
Descriptor
Available
as
Data RAM
Maximum Memory
Used: 64 bytes
Maximum BDs:
16 (BD0 to BD15)
Note: Memory area not shown to scale.
2200h
203Fh
2000h
EP0 OUT
Even Descriptor
PPB<1:0> = 01
Ping-Pong Buffer
on EP0 OUT
EP0 IN
Descriptor
EP1 OUT
Descriptor
EP7 IN
Descriptor
Maximum Memory
Used: 68 bytes
Maximum BDs:
17 (BD0 to BD15)
2200h
2043h
2000h
EP0 OUT
Even Descriptor
PPB<1:0> = 10
Ping-Pong
Buffers on all EPs
EP0 OUT
Odd Descriptor
EP0 IN
Even Descriptor
EP0 IN
Odd Descriptor
EP7 IN
Odd Descriptor
Maximum Memory
Used: 128 bytes
Maximum BDs:
32 (BD0 to BD31)
2000h
EP0 OUT
Descriptor
PPB<1:0> = 11
Ping-Pong Buffers on all
other EPs except EP0
EP0 IN
Descriptor
EP7 IN
Odd Descriptor
Maximum Memory
Used: 120 bytes
Maximum BDs:
30 (BD0 to BD14
2200h
2077h
EP0 OUT
Odd Descriptor
EP1 IN
Descriptor
EP1 OUT
Even Descriptor
EP1 OUT
Odd Descriptor
EP1 IN
Even Descriptor
EP1 IN
Odd Descriptor
EP1 OUT
Even Descriptor
EP1 OUT
Odd Descriptor
EP1 IN
Even Descriptor
EP1 IN
Odd Descriptor
207Fh
2200h
Available
as
Data RAM
Available
as
Data RAM
Available
as
Data RAM