问 我看了关于DC80C400的一个介绍之后,对以下问题有疑问，请高手指点:

1.文中说"ROMless",但又说"IEEE 802.3 Ethernet Interface with TCP/IP in ROM",究竟是有ROM,还是没有?还是说有ROM,但已经固化了TCP/IP,不可访问,并且没有其它ROM.

2.在那里可以下载到有关DC80C400内嵌的操作系统的资料。

3.用户开发的程序在哪里运行？是不是要外接RAM？

多谢！

全文部分内容如下：
8051 based High-Speed Micro with 4 DPTRs, ROMless,
WDT, 3 Serial Ports, CAN Controller, 4 Timers/Counters,
IEEE 802.3 Ethernet Interface with TCP/IP in ROM,
1-Wire Net Controller, 64 I/O Lines + Address/Data Bus,
16 Interrupts/3 Priority Levels, 256 Bytes On-chip RAM,
9K Bytes On-chip SRAM, 16/32-bit Math Coprocessor,
Optional 10-Bit Stack Pointer,
Addresses up to 16M Bytes External Memory
*** IMPORTANT ***
The PK51 Professional Developer's Kit is required
if you wish to create programs that access the
16M Byte external address space.

答 1: 对不起，片名写错，是DS80C400.Dallas Semiconductor出品