From b8f6322b98d9c61dac5e5bf774e07cebd81d148a Mon Sep 17 00:00:00 2001 From: William Harrington Date: Wed, 22 May 2019 16:37:53 -0500 Subject: Add DS1302 Real Time Clock Module for RC2014 --- addon/DS1302/README.md | 49 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 49 insertions(+) create mode 100644 addon/DS1302/README.md (limited to 'addon/DS1302') diff --git a/addon/DS1302/README.md b/addon/DS1302/README.md new file mode 100644 index 0000000..854dbf1 --- /dev/null +++ b/addon/DS1302/README.md @@ -0,0 +1,49 @@ +# DS1302 Real Time Clock for the RC2014 computer + +![Picture of the board](./board-r1.jpg?raw=true) + +## The board +RomWBW has code to support a DS1302 Real Time Clock, enabling files to be timestamped and other timekeeping operations. This board implements the clock in a standard way for the RC2014. + +## What can you use this for? +Telling the time :) + +## Getting started with RomWBW + +Set ```DSRTCENABLE``` to true in the configuration and rebuild your ROM image. + +On startup you will see the time shown. + +![Boot](./boot.png?raw=true) + +ZSystem has more complete support for time utilities than CP/M. After booting into ZSystem by pressing Z, Run ```ldds``` to load the resident time driver. ```td``` can then be used to set the time as well as view it. + +In CP/M ```RTC.com``` can be used for querying and setting the clock but it is very basic. + +## Jumpers +SW1 - Address configuration. For the default address of 0xC0, set switches 5 and 6 to on. + +## Bill Of Materials + +Reference| Value|Farnell part no|Rapid part no|Digi-key part no| +---------|------|---------------|-------------|----------------| +P1|1x39 right angled pin header|||732-5350-ND| +BT1|Keystone 106 20mm battery holder for CR2032|1650672||36-106-ND| +BT1|CR2032 battery|||P189-ND| +U1|CD74HCT688E COMPARATOR, SINGLE, PDIP-20|2407104||296-2131-5-ND| +U2|SN74HCT125N LOGIC, BUS BUFF TRI-ST QD, 14DIP|1739676||296-8386-5-ND| +U3|CD74HCT174E 74HCT CMOS, 74HCT174, DIP16, 5.5V|1105983||296-2100-5-ND| +U4|DS1302N+ RTC W/ RAM, 248B, D-D-M-Y, HH:MM:SS, DIP|2515367||DS1302N+-ND| +U5|SN74HCT32N IC, QUAD 2-INPUT OR, 74HCT32, DIP14|9591982||296-1615-5-ND| +C1-5|0.1uF MLCC capacitor|||BC2665CT-ND| +Y1|32.768 kHz crystal|9712887||535-9034-ND| +RN1|10k 8 Pin Commoned Resistor Network||63-0125|4608X-1-103LF-ND| +SW1|6 way DIL switch||80-0338|CT2066-ND| +U1|CONN IC DIP SOCKET 20POS TIN|||AE10015-ND| +U2|CONN IC DIP SOCKET 14POS TIN|||AE10012-ND| +U3|CONN IC DIP SOCKET 16POS TIN|||AE10013-ND| +U4|CONN IC DIP SOCKET 8POS TIN|||AE10011-ND| +U5|CONN IC DIP SOCKET 14POS TIN|||AE10012-ND| + +## Construction tips +The footprint for the battery holder is designed for a Keystone 106, other battery holders should work if the pins are ~20.5mm apart, which seems to be fairly standard. -- cgit v1.2.3-54-g00ecf