Oki JOB60851, User Manual, Page: 52 / 67

Chapter 4 Software Development
page 4-17
4-3. USB Bits and Pieces
4-3-1. Device Controller Specifications
Table 4.3.1 summarizes the ML60851C specifications. For detailed device specifications, see the
data sheet (Ml60851c.pdf).
Table 4.3.1. ML60851C Specifications
Data transfer speed Full speed (12 Mb/s) only
Data flow type
Endpoint Direction Buffer size
In 8bytes Control EP0
Out 8bytes
EP1 In and out 64 bytes
×
2 Bulk
EP2 In and out 64bytes
Interrupt EP3 In 8bytes
Endpoint
specifications
Isochronous - - -
DMA
8/16-bit DMA request function (Endpoint 1: DMA request and acknowledge)
Power supply Vcc3=3.0 to3.6V, Vcc5=3.0 to 5.5V
Interface to 5-volt microcontroller with local power supply (Vcc5)
Package 44-pin QFP or TQFP
4-3-2. Overview of ML60851C Operation
Figure 4.3.1 is a block diagram for ML60851C internals. The basic structure and operation are both
simple. The receiver digitizes the inputs from the USB differential (D+/D-) data bus for the protocol
engine. The phase-locked loop (DPLL) synchronizes the protocol engine with the bus clock.
The protocol engine executes the transactions. It analyzes the time-multiplexed packets over the
USB bus looking for transactions including its assigned address. If it finds one, it analyzes the
request from the host to the corresponding endpoint and then accesses the appropriate buffer for
receiving from or transmitting to the USB bus.