I have two R6501 IC’s. One came with the Glitchworks GW-R65X1QSBC-1 kit, a R6501Q. The other from ebay, a R6501AQ (A for 2MHz).
The Rockwell R6501 is a NMOS-3 microcomputer on a chip. It has an enhanced 6502 CPU, 192 bytes RAM, and a VIA interface (2 16 bit counters, 32 I/O lines a serial port, 10 interrupts.
The 6502 has RMB and SMB BBS and BBR instructions added. I/O in zero page (00-1F, Stack in zeropage (040-FF). See the datasheets for more information.
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R6501Q One Chip Microprozessor Rockwell datasheet |
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R6501Q datasheet 1984 |
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R6501 R6511 datasheet 1987 |
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Glitchworks GW-R65X1QSBC-1 kit manual |
Glitchworks GW-R65X1QSBC-1
I am building the Glitchworks GW-R65X1QSBC-1, a SBC around the 6501Q.
The Glitch Works R6501Q/R6511Q Single Board Computer (SBC) is designed to support Rockwell’s single-chip microcomputer processors in QUIP-64 (double zig-zag) packages. These processors contain an enhanced 6502 processor core, 192 bytes of onboard static RAM, hardware serial communications channel, up to 32 bits of parallel I/O, and two counter/timer modules.
The R65X1Q SBC is designed to work with the Rockwell R6501Q, R6511Q, R6501AQ, or R6511AQ. The SBC provides the following features:
- 32 KB static RAM, compatible with Ferroelectric RAM (FeRAM)
- 32 KB ROM, EEPROM, or FeRAM in 4K pages, in-board programmable
- Serial console via onboard UART
- ROM paging and switch-out
- Debounced reset and power supply supervisory circuit
- Glitchbus expansion header
- Glitchbus I/O mapped as a 256 byte memory page at 0xEF00
A full assembly and user’s manual, including schematics, is available as a PDF download. Additionally, full parts kits and assembled units include a customized and enhanced version of Steve Wozniak’s 6502 ROM monitor (link to sources provided below).
The default software load includes a 32K ROMFS image with:
- eWoz 1.2 for Glitch Works R65X1Q SBC
- Tiny BASIC customized for Rockwell R65X1Q
- Rockwell RSC-FORTH 1.7 configuration 2
- A modified version of the Ohio Scientific memory test
Updates to default ROMFS software loads are provided as a hex loadable file which allows in-system updates of the EEPROM, removing the need for an EPROM programmer.
Patches for RSC-Forth
The patches directory on the Glitchworks github site contains patchfiles for changing aspects of the original RCS-Forth ROM images, also for RCS-Forth Configuration 3 (requires extra hardware):
– R65FK2P_R6501Q-SBC.patch Patches for use with Glitch Works R6501Q SBC
– R65FK3P_8_bit_serial.patch Patches to use 8N1 for serial parameters
– R65FK3P_R6501Q-SBC.patch Patches for use with Glitch Works R6501Q SBC and 32K Memory Board
See also:
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