AN2131-DK001 Cypress Semiconductor Corp, AN2131-DK001 Datasheet - Page 56

• Manufacturer Part Number: AN2131-DK001
• Description: KIT EZ-USB DEVELOPMENT BOARD
• Manufacturer: Cypress Semiconductor Corp

Specifications of AN2131-DK001

• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Other names: 428-1333

In the example shown in Figure 3-3, only endpoints 0-IN through 3-IN are used for the
USB function, so the data RAM (shaded) can be extended to 0x1D7F.
If an application uses none of the 16 EZ-USB isochronous endpoints, the 8051 can set the
ISODISAB bit in the ISOCTL register to disable all 16 isochronous endpoints, and make
the 2-KB of isochronous FIFO RAM available as 8051 data RAM at 0x2000-0x27FF.
Setting ISODISAB=1 is an all or nothing choice, as all 16 isochronous endpoints are dis-
abled. An application that sets this bit must never attempt to transfer data over an isochro-
nous endpoint.
The memory map figures in the remainder of this chapter assume that ISODISAB=0, the
default (and normal) case.
EZ-USB TRM v1.9
Figure 3-3. Unused Bulk Endpoint Buffers (Shaded) Used as Data Memory
Chapter 3. EZ-USB Memory
1F40
1F00
1EC0
1E80
1E40
1E00
1DC0
1D80
1D40
1D00
1CC0
1C80
1C40
1C00
1BC0
1B80
1B40
1B3F
0000
Code/Data
EP07OUT
EP0OUT
EP1OUT
EP2OUT
EP3OUT
EP4OUT
EP5OUT
EP06UT
EP0IN
EP1IN
EP2IN
EP3IN
EP4IN
EP5IN
EP6IN
EP7IN
RAM
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