Datasheet

91
32142D–06/2013
ATUC64/128/256L3/4U
Figure 8-5. Memory organization
Each descriptor of an endpoint n consists of four words.
• The address of the endpoint and the bank used (EPn_ADDR_BK0/1).
• The packet size information for the endpoint and bank (EPn_PCKSIZE_BK0/1):
Table 8-3. EPn_PCKSIZE_BK0/1 structure
– AUTO_ZLP: Auto zero length packet, see ”Multi packet mode for IN endpoints” on
page 96.
– MULTI_PACKET_SIZE: see ”Multi packet mode and single packet mode.” on page
93.
– BYTE_COUNT: see ”Multi packet mode and single packet mode.” on page 93.
31 30:16 15 14:0
AUTO_ZLP MULTI_PACKET_SIZE - BYTE_COUNT
EPn BK0
EP0_C TR_STA_BK0
EP0_PCKSIZE_BK0
EP0_ADDR_BK0
UDESCA
Growing Memory Addresses
Descriptor EP0
Reserved
EP0_CTR _STA_BK1
EP0_PCKSIZE_BK1
EP0_ADDR_BK1
Reserved
Bank0
Bank1
+0x000
+0x004
+0x008
+0x00C
+0x010
+0x014
+0x018
+0x01C
EP1_C TR_STA_BK0
EP1_PCKSIZE_BK0
EP1_ADDR_BK0
Descriptor EP1
Reserved
EP1_CTR _STA_BK1
EP1_PCKSIZE_BK1
EP1_ADDR_BK1
Reserved
Bank0
Bank1
+0x020
+0x024
+0x028
+0x02C
+0x030
+0x034
+0x038
+0x03C
EPn_C TR_STA_BK0
EPn_PCKSIZE_BK0
EPn_ADDR_BK0
Reserved
EPn_CTR _STA_BK1
EPn_PCKSIZE_BK1
EPn_ADDR_BK1
Reserved
Bank0
Bank1
Descriptor EPn
EPn BK1
USB descriptors
USB Buffers