On Wednesday 03 August 2005 19:16, Rony Bill wrote:
Trevor Warren wrote:
MP3_PCB_ASSEM MP3 Player Board, Fully Assembled and Tested $150 MP3_DISPLAY LCD Display For MP3 Player, 24x8, with Pushbuttons and Cables $42 CABLE_IDE_LAPTOP Cable for Laptop (2.5 inch) IDE Hard Drive, 1.4 Inch Length $9 STANDOFF Standoff Set For Mounting Laptop Hard Drive $3 PWR_12VDC 12 Volt DC Power Adaptor (US only) $8 SIMM_32M Standard 72 Pin SIMM, 32 Megs, Used $8 Totals :- 220$
For learning purposes see if you can manage with a normal HDD instead of a laptop's. That will bring down your costs and use locally available cables. Make your own power supply.
Are the cables available?.
JTD can guide on this. Can a pci i/o card (Rs. 1k2 only) be used with some extra circuit (without any mobo) to get access to a HDD
You can use an 8bit 8052 micon to connect an ide device (cdrom / hdd). You will get raw access at about 300kbps. Afaik filesystem drivers on 8052 will be useless due to performance issues (maybe dosfs on a 50Mhz device will work).
and then convert its signals into mp3 using an open source program loaded into a memory chip?
Software decoding of MP3 on 8 bitters is a no no. Hardware decoders / encoders yes. But the cost of 32bit arm / mips / sh micons with onchip flash, ram and mp3 encoder /decoders is about $8 retail. Adding an ide is easy. Or even better add usb driver ic at $1. Get USB to ide disk dabba from Lamington Rd. stick in 400gb hdd and freak out.
The problem is that there is vast array of devices available to do a given job. Couple that with the even wider choice of GNU software and the decision making process becomes never ending - even for a fun thing. Was the 8051 and ISA better? I need to think before i decide |-/
Can pci standards be used on a pci card without a pci slot mobo?
No. The PCI signals require special drivers to reduce signal bounce and switching power consumption in order to run at high speeds, apart from other requirements like irq routing and dynamic address and dma assignment etc. The old ISA bus was simple to interface with but was pathetic at i/o. Even on a 386 33MHz signal bounce was a nightmare with dma transfers. The RD and WR signals would pulse twice causing all sorts of problems.
rgds jtd