ON 20130909@10:48:27 PM at page:
On a web page you were interested in at:
http://techref.massmind.org/Techref/zilog/index.htm#41526.9503125
James Newton[JMN-EFP-786] See also:
http://www.righto.com/2013/09/the-z-80-has-4-bit-alu-heres-how-it.html
Did you know the original Z80 had a 4 (that is FOUR) bit ALU? For each 8 bit operation, it did the low 4 bits first, saved the result in an internal register and then did the high 4 bits which it released along with the saved low bits as an 8 bit result.
ON 20130909@11:07:05 PM at page:
On a web page you were interested in at:
http://techref.massmind.org/Techref/logic/tutorial.htm#41526.9632523148
James Newton[JMN-EFP-786] See also:
http://www.bigmessowires.com/category/nibbler/
A 4 bit computer design entirely from 7400 series logic chips.
ON 20130913@8:29:07 AM at page:
On a web page you were interested in at:
http://massmind.org/Techref/microchip/alternatives.htm#41530.1533217593
James Newton[JMN-EFP-786] published post 41530.1533217593
adrian.wallis@btinternet.com refers to
http://www.kanda.com/products/Kanda/STK-PIC.html
Kanda complete, low cost, PIC development and training kit includes comprehensive development board and PICKit2 programmer and debugger. Based around a Get Going with... PIC book, it includes sample code in C and assembler, schematics, datasheets and projects.
ON 20130913@8:29:32 AM at page:
On a web page you were interested in at:
http://massmind.org/Techref/microchip/alternatives.htm#40529.5180092593
James Newton[JMN-EFP-786] published post 40529.5180092593
http://gadgetforge.gadgetfactory.net/gf/project/cocoon_pic2/
A low-cost PIC development platform using PIC18F44J50 controller with all
its remappable pins available in headers and onboard set of buttons and LEDs
for user interface, and a USB device to communicate with a
host.
ON 20130917@10:39:24 AM at page:
On a web page you were interested in at:
http://www.piclist.com/Techref/microchip/crcs.htm#41534.2568634259
James Newton[JMN-EFP-786] published post 41534.2568634259
jhm@ukr.net
I've made PICC18 specific highly optimised routine for CRC16 CCITT calculation. It takes 16 cycles per byte for CRC calculation plus 7 cycles for data fetching from array.
uint16 Crc16 (uint8* ptr, uint8 len)
{
uint8 data, i;
union
{
uint8 Byte[2];
uint16 Word;
} CRC16;
CRC16.Word = 0xFFFF;
for(i=0; i<=len; i++)
{
data = ptr[i] ^ CRC16.Byte[0];
data ^= data << 4;
data * 8;
CRC16.Byte[0] = CRC16.Byte[1] ^ (data >> 4) ^ PRODL;
CRC16.Byte[1] = data ^ PRODH;
}
return CRC16.Word;
}
ON 20130917@10:40:19 AM at page:
On a web page you were interested in at:
http://www.piclist.com/Techref/microchip/crcs.htm#
James Newton[JMN-EFP-786] edited the page. Difference:
http://www.piclist.com/techref/diff.asp?url=\Techref\microchip\crcs.htm&version=3