AN2131SC Cypress Semiconductor Corp, AN2131SC Datasheet - Page 156

• Manufacturer Part Number: AN2131SC
• Description: IC MCU 8051 8K RAM 24MHZ 44QFP
• Manufacturer: Cypress Semiconductor Corp
• Series: EZ-USB®r

Specifications of AN2131SC

• Applications: USB Microcontroller
• Core Processor: 8051
• Program Memory Type: ROMless
• Controller Series: AN213x
• Ram Size: 8K x 8
• Interface: I²C, USB
• Number Of I /o: 16
• Voltage - Supply: 3 V ~ 3.6 V
• Operating Temperature: 0°C ~ 70°C
• Mounting Type: Surface Mount
• Package / Case: 44-QFP
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Other names: 428-1306; AN2131SC

8.6.2 Fast Reads
Fast reads are illustrated in Figure 8-9. When the fast mode is enabled, the DPTR points
to an isochronous OUT FIFO register, and the 8051 executes the “movx @dptr,a” instruc-
tion, the EZ-USB core breaks the data path from the accumulator to the IN FIFO register,
and instead writes the IN FIFO using outside data from D[7..0]. The EZ-USB core syn-
chronizes this transfer by generating a FIFO Read Strobe FRD# (Fast Read). A choice of
eight waveform is available for the read strobe, as shown in the next section.
The 8051 sets bits in the FASTXFR register to select the fast ISO and/or fast BULK mode
and to adjust the timing and polarity of the read and write strobes FRD# and FWR#.
The 8051 sets FISO=1 to select the fast ISO mode and FBLK=1 to select the fast Bulk
mode. The 8051 selects read and write strobe pulse polarities with the RPOL and WPOL
bits, where 0=active low, and 1=active high. Read and write strobe timings are set by
EZ-USB TRM v1.9
FASTXFR
8.7
FISO
b7
Fast Transfer Timing
FBLK
DPTR
Figure 8-10. The FASTXFR Register Controls FRD# and FWR# Strobes
b6
Figure 8-9. Fast Transfer, Outside Memory to EZ-USB
RPOL
b5
Fast Transfer Control
Chapter 8. EZ-USB CPU
RMOD1
b4
ISO IN FIFO
Accumulator
RMOD0
b3
FRD#
D[7..0]
WPOL
b2
WMOD1
b1
External FIFO
or ASIC
WMOD0
Page 8-11
b0
7FE2