EZ-USB Datasheet, PDF (40/334 Pages) Cypress Semiconductor – The EZ-USB USB Integrated Circuit

Table 1-3. EZ-USB Series 2100 Pinouts by Pin Function
2131Q
2121S
2122S
2131S
2125S
2126S
2135S
2136S
2122T
2126T
21 10 10 11 11
18 7
7
7
7
1 43 43 47 47
77 41 41 45 45
79 42 42 46 46
7-12, N/A N/A N/A N/A
15, 16,
26-29,
34-37
48-51, N/A 24-27, N/A 26-29,
57-60
28-31
30-33
80 N/A N/A N/A N/A
61 32 32 35 35
25 13 13 14 14
Name
AVCC
AGND
DISCON#
USBD
USBD
A0-A5, A6,
A7, A8-A11,
A12-A15
D0-D3, D4-
D7
PSEN#
BKPT
RESET
Type Default
Description
Power N/A Analog Vcc. This signal provides power to the ana-
log section of the chip.
Power N/A Analog Ground. Connect to ground with as short a
path as possible.
Output HI Disconnect. This pin is controlled by two bits,
DISCOE and DISCON. When DISCOE=0, the pin
floats. When DISCOE=1, it drives. When
DISCOE=1, the driven logic level is the inverse of
the DISCON bit.
I/O/Z Z USB D- signal. Connect to the USB D- signal
through a 24-ohm resistor.
I/O/Z Z USB D+ signal. Connect to the USB D+ pin through
a 24-ohm resistor.
Output 0x0000 8051 Address bus. This bus is driven at all times.
When the 8051 is addressing internal RAM it reflects
the internal address.
I/O/Z Z 8051 Data bus. This bi-directional bus is high-
impedance when inactive, input for bus reads, and
output for bus writes. The data bus is also used to
transfer data directly to and from internal EZ-USB
FIFOs under control of the FRD# and FWR#
strobes. D0-D7 are active only for external bus
accesses, and are driven low in suspend.
Output H Program Store Enable. This active-low signal indi-
cates a code fetch from external memory. It is active
for program memory fetches above 0x1B40 when
the EA pin is LO, or above 0x0000 when the EA
pin is HI.
Output 0 Breakpoint. This pin goes active (high) when the
8051 address bus matches the BPADDRH/L regis-
ters and breakpoints are enabled in the USBBAV
register (BPEN=1). If the BPPULSE bit in the
USBBAV register is HI, this signal pulses high for
eight 24-MHz clocks. If the BPPULSE bit is LO, the
signal remains high until the 8051 clears the BREAK
bit (by writing 1 to it) in the USBBAV register.
Input N/A Active High Reset. Resets the 8051 and the USB
SIE. This pin is normally tied to ground through a
10K-ohm resistor and to Vcc through a 1 µF capac-
itor.
EZ-USB TRM v1.9
Chapter 1. Introducing EZ-USB
Page 1-23